A novel fluorescent probe based on triphenylamine for detecting sulfur dioxide derivatives

According to the nucleophilicity of sulfur dioxide derivatives, a reactive fluorescent probe was designed and synthesized by linking triphenylamine with benzoindole.

Pressure-Driven Two-Step Second-Harmonic-Generation Switching in BiOIO3

Materials with multi-stabilities controllable by external stimuli are potential for high-capacity information storage and switch devices. Herein, we report the observation of pressure-driven two-step second-harmonic-generation (SHG) switching in polar BiOIO 3 for the first time. Structure analyses reveal two pressure-induced phase transitions in BiOIO 3 from the ambient noncentrosymmetric phase (SHG-high) to an intermediate noncentrosymmetric phase (SHG-intermediate) and then to a centrosymmetric phase (SHG-off). The three-state SHG switching is inspected by in-situ high-pressure powder SHG and polarization-dependent single-crystal SHG measurements. Local structure analyses based on the in-situ Raman spectra and X-ray absorption spectra reveal that the SHG switching are caused by the step-wise suppression of lone-pair electrons on the [IO 3 ] - units. The dramatic evolution of the functional units under compression also leads to subtle changes of the optical absorption edge of BiOIO 3 . Materials with switchable multiple stabilities provide a state-of-art platform for next-generation switch and information storage devices.

MiR-18a Inhibits PI3K/AKT Signaling Pathway to Regulate PDGF BB-Induced Airway Smooth Muscle Cell Proliferation and Phenotypic Transformation

The increased proliferation and migration of airway smooth muscle cells (ASMCs) is a key process in the formation of airway remodeling in asthma. In this study, we focused on the expression of mircoRNA-18a (miR-18a) in airway remodeling in bronchial asthma and its related mechanisms. ASMCs are induced by platelet-derived growth factor BB (PDGF-BB) for in vitro airway remodeling. The expression of miR-18a in sputum of asthmatic patients and healthy volunteers was detected by qRT-PCR. The expression of miR-18a was over-expressed or interfered with in PDGF-BB-treated ASMCs. Cell proliferation, apoptosis and migration were detected by MTT, flow cytometry and Transwell, respectively; the expression of contractile phenotype marker proteins (SM-22α, α-SM-actin, calponin) and key molecules of the phosphatidylinositol 3-kinase (PI3K)/AKT pathway (PI3K, p-PI3K, AKT and p-AKT) in ASMCs were detected by Western blot. The expression of miR-18a was down-regulated in the sputum and PDGF-BB-treated ASMCs of asthma patients. PDGF-BB could promote the proliferation and migration of ASMCs and inhibit their apoptosis; it could also promote the phenotypic transformation of ASMCs and activate the PI3K/AKT pathway. MiR-18a could inhibit the proliferation, migration ability and phenotypic transformation of ASMCs induced by PDGF-BB to a certain extent and alleviate the effect of PDGF-BB in supressing apoptosis, while miR-18a could inhibit the activation of the PI3K/AKT pathway. MiR-18a inhibits PDGF-BB-induced proliferation, migration and phenotypic conversion of ASMCs by inhibiting the PI3K/AKT pathway, thus attenuating airway remodeling in asthma.

P-OGC14 Global Level of Harm Upper Gastrointestinal (GLEOHUG) – a multinational gastric cancer cross- sectional appraisal

Background

Gastric cancer (GC) is the 5^th most common malignancy and remains one of the major causes of worldwide cancer-related deaths. COVID-19 pandemic has had a significant impact on the provision of cancer care. This study aims to overview the global standpoint of gastric cancer patients (GCP) during the first year of the pandemic.

Methods

The Upper Gastrointestinal Surgeons (TUGS), within its Global Level of Harm Project, designed an online cross-sectional survey to assess how gastric cancer patient’s management changed during the first year of the pandemic. The questionnaire included 33 questions about expertise, kind of health system, hospital organization and screening policies, personal protective equipment (PPE), change in patient’s characteristics, preoperative, operative and postoperative management of GCP.

Results

There were 209 participants from 178 centres & 50 countries). Results showed: most hospitals (88,18%) had restricted areas for COVID-19 patients; 53.58% of surgeons were redeployed; most frequent COVID-19 screening method was PCR (78,82%) & chest CT-scan (25,62%), and 55.98% lack full PPE. Preoperative management: 43.16% noted reduction in multidisciplinary teams (MDT) meetings; 28,42% increase in cT2 or higher GCP; 34,74% increase in metastatic (M1) GCP; 26,84% increase in patients receiving definitive palliative treatment; 23,68% note increase in frail patients; 50% increase in waiting list time; and 41,58% faced problems in the provision of oncological treatment. Operative management: 54,50% decrease in elective gastrectomies; 29,10% increase in urgent/semi-urgent gastrectomies; 37,04% decrease in the number of minimally-invasive gastrectomies (MIG); & 18,52% increase in the number of palliative surgeries. Postoperative management: 16,48% increase in the overall complication rate (OCR); 12,64% increase in the number of Clavien-Dindo 3 or higher complications; 8,13% increase in the leak rate; increase in pulmonary infections (26,79%) and bowel obstruction (2,39%); 44,51% note postoperative COVID-19; 15,38% increase in 30-days mortality; 23,08% mortality due to COVID-19 infection; 17,58% increase in the need for adjuvant treatment. Most patients were postoperatively assessed either through a face-to-face consultation or a hybrid approach.

Conclusions

COVID-19 pandemic has affected gastric cancer management by decreased frequency of MDT’s, higher clinical-stage migration and fuelled frailty. The pandemic increased waiting list time, the number of urgent and palliative surgeries, OCR, Clavie-Dindo 3 or higher complications, leak rate, and pulmonary infections. There was a noticeable high rate of postoperative COVID-19 infection and associated mortality. Further multicentric studies are warranted to affirm these findings.

A ratiometric and colorimetric fluorescent probe designed based on FRET for detecting SO32-/HSO3- in living cells and mice

Based on the principle of FRET, we have developed a ratiometric and colorimetric fluorescent probe TFBN, which can specifically recognize SO₂ derivatives (SO₃^2-/HSO₃^-), and exhibit a transition from red to green fluorescence under 405 nm excitation. The probe TFBN owns the advantages of short response time (<3 min), quantitative detection SO₂ derivatives in two linear ranges, extremely low detection limit (39 nM), large Stokes shift (239 nm) and wide emission window gap (140 nm). In addition, the NBC structure was used as a fluorescent donor for FRET probes for the first time, which expanded the diversity of donors. Importantly, with low toxicity and good biocompatibility, the probe TFBN successfully detects exogenous and endogenous sulfites in living cells. These characteristics endow the probe TFBN can be successfully used in living cells and mouse imaging.

ac4C acetylation of RUNX2 catalyzed by NAT10 spurs osteogenesis of BMSCs and prevents ovariectomy-induced bone loss

N-acetyltransferase 10 (NAT10) is the key enzyme for N4-acetylcytidine (ac4C) modification of mRNA, which participates in various cellular processes and is related to many diseases. Here, we explore the relationships among osteoblast differentiation, NAT10, and ac4C, and we found that NAT0 expression and the ac4C level of total RNA were decreased in the bone tissues of bilateral ovariectomized (OVX) mice and osteoporosis patients. Adenoviruses overexpressing NAT10 reversed bone loss, and Remodelin, an NAT10 inhibitor, enhanced the loss of bone mass in OVX mice. Moreover, bone marrow-derived mesenchymal stem cells (BMSCs) with low-level ac4C modification formed fewer calcium nodules in vitro with NAT10 silencing, whereas BMSCs with high-level ac4C modification formed more calcium nodules with NAT10 overexpression. Moreover, we demonstrated that the ac4C level of runt-related transcription factor 2 (RUNX2) mRNA was increased after BMSCs were cultured in osteogenic medium (OM) and decreased after NAT10 silencing. The RUNX2 mRNA half-life and protein expression decreased after silencing NAT10 in BMSCs. Therefore, NAT10-based ac4C modification promotes the osteogenic differentiation of BMSCs by regulating the RUNX2 ac4C level. Because abnormal levels of NAT10 are probably one of the mechanisms responsible for osteoporosis, NAT10 is a new potential therapeutic target for this disease.

Role of miR-27a in the regulation of cellular function via the inhibition of MAP2K4 in patients with asthma

Asthma is a respiratory disease with a clinically high incidence, and repeated attacks of asthma severely affect the quality of life and even pose a threat to health, leading to severe burdens on families and even the society. A thorough understanding of the pathogenesis of asthma is essential for the prevention and treatment of asthma. This study aimed to examine the effect of the microRNA miR-27a on asthma and its relationship with mitogen activated protein kinase 4 (MAP2K4). Patients with asthma admitted to our hospital from August 2016 to August 2018 and healthy participants in the same period were included in this prospective analysis. The mRNA expression levels of miR-27a and MAP2K4 in peripheral blood were determined. Airway smooth muscle cells (ASMCs) were used to study the effects of miR-27a and MAP2K4 on cell biological behavior. The relationship between miR-27a and MAP2K4 was verified using dual-luciferase reporter assay. miR-27a expression was increased and MAP2K4 mRNA expression was decreased in asthma (P < 0.05). Increasing miR-27a expression and inhibiting MAP2K4 expression could enhance the activity of ASMCs, whereas inhibiting miR-27a expression and increasing MAP2K4 expression had the opposite effect (P < 0.05). Dual-luciferase reporter assay results showed that the fluorescence activity of MAP2K4-wild type was inhibited by increased miR-27a expression (P < 0.05). miR-27a promotes the proliferation and invasion of ASMCs by targeting MAP2K4 and is involved in the occurrence of asthma.

Time-resolved fluorescence determination of albumin using ZnGeO:Mn luminescence nanorods modified with polydopamine nanoparticles

A novel time-resolved fluorescence (TRF) pobe is constructed to detect human serum albumin (HSA) by exploiting ZnGeO:Mn persistent luminescence nanorods (ZnGeO:Mn PLNRs) and polydopamine nanoparticles (PDA NPs). HSA-induced dynamic quenching leads to the fluorescence decrease of ZnGeO:Mn PLNRs, providing the basis for quantitative analysis of HSA. The excellent photo-thermal conversion performance of PDA NPs is helpful to the collision process between ZnGeO:Mn PLNRs and HSA, inducing significant improvement of sensitivity. HSA is quantified by measuring time-resolved fluorescence at 540 nm under excitation of 250-nm light. Under optimal conditions, HSA in the linear range 0.1-100 ng mL^-1 are detected by this PDA-mediated ZnGeO:Mn probe with high sensitivity and selectivity, and the detection limit is 36 pg mL^-1 (3σ/s). The RSD for the quantification of HSA (5 ng mL^-1, n = 11) is 5.2%. The practicability of this TRF probe is confirmed by accurate monitoring HSA contents in urine samples, giving rise to satisfactory spiking recoveries of 96.2-106.0%.

Effect of ascorbic acid and citric acid on bioavailability of iron from Tegillarca granosa via an in vitro digestion/Caco-2 cell culture system

Iron deficiency anaemia (IDA) has been receiving worldwide attention. Developing safe and effective iron supplements is of great significance for IDA treatment. Tegillarca granosa (T. granosa), a traditional aquaculture bivalve species in China, is considered to be an excellent source of micronutrients, but the distribution and bioavailability of these minerals have yet to be investigated. The present research was conducted to determine the contents and in vitro enzymatic digestibility of minerals in T. granosa, using beef and wheat flour as reference foods. Meanwhile, two iron-binding proteins, hemoglobin and ferritin, were extracted from T. granosa, and their structures, iron accessibility and bioavailability were investigated. Moreover, the effects of ascorbic acid (AA) and citric acid (CA), two commonly applied dietary factors, on these parameters were evaluated. Our results indicated that the mineral levels varied significantly among different food matrices, with T. granosa showing the highest contents of the tested elements. Comparison of iron absorption of meat versus wheat flour and hemoglobin versus ferritin confirmed that heme iron exhibited higher bioavailability than non-heme iron. The addition of the two organic acids notably enhanced the cellular iron uptake of T. granosa-derived proteins. This could be because AA/CA weakened hydrogen bonds within proteins and caused disordered secondary structures, thereby improving their enzymatic digestibility and releasing more soluble iron to be available for absorption. The results of this study provided a basis for the development of T. granosa-derived protein-based iron supplements, promoting the diverse utilization of marine aquatic resources.

LINC00205, a YY1-modulated lncRNA, serves as a sponge for miR-26a-5p facilitating the proliferation of hepatocellular carcinoma cells by elevating CDK6

OBJECTIVE

LINC00205, a bidirectional lncRNA, located at human chromosome 21q22.3, was recently characterized as an oncogenic molecule contributing to cell proliferation in several cancers, including hepatocellular carcinoma (HCC). In the present study, we aim to probe the new molecular mechanism for LINC00205 controlling the proliferation of HCC cells.

PATIENTS AND METHODS

The expression status of LINC00205, miR-26a-5p, as well as CDK6 in HCC tissues/cell lines was determined by quantitative real-time PCR (qPCR). The cell proliferative activity was measured by using the Cell Counting Kit (CCK)-8 assay. Flow cytometry was performed to analyze cell cycle progression and apoptosis induction. The interaction among LINC00205, miR-26a-5p and CDK6, as well as transcription efficiency of LINC00205 promoter were examined by Dual-Luciferase reporter assay. Western blot was conducted to evaluate the protein levels of CDK6 in SNU-449 cells. The direct interplay between YY1 and LINC00205 promoter was detected by ChIP-qPCR.

RESULTS

LINC00205 was strongly expressed in HCC tissues and cell lines. Elevated LINC00205 expression was positively associated with worse prognosis as well as pathological grade in HCC. Suppression of LINC00205 could impede the proliferation of HCC cells by triggering the G0/G1-phase cell cycle arrest and apoptosis in vitro. Mechanistically, we illustrated that LINC00205 could accelerate the proliferation of HCC cells by boosting CDK6 expression via sponging miR-26a-5p. Moreover, we unveiled that LINC00205 could be activated by transcription factor Yin Yang-1 (YY1) as its direct downstream target.

CONCLUSIONS

LINC00205, a novel YY1-modulated lncRNA, can facilitate the proliferation of HCC cells through YY1/miR-26a-5p/CDK6 pathway, and may serve as a promising diagnostic biomarker and therapeutic target for HCC.

MYOD1 c.365G&gt;T, p.L122R Variant Detection by Droplet Digital PCR (ddPCR)

Introduction/Objective

Rhabomyosarcomas (RMS) are a group of skeletal muscle tumors that include embryonal, alveolar, pleomorphic, spindle cell/sclerosing subtypes (SC/SRMS). Spindle cell RMS occurs in both adult and pediatric populations, and is associated with either more aggressive or better clinical outcomes respectively. A recurrent hotspot variant in MYOD1, p.L122R (NM_002478.4 c.365G&gt;T), has been described in SC/SRMS. The classification of this diagnosis is evolving, with VGLL2 and NCOA2 fusions defining the diagnosis in young children, and MYOD1 p.L122R defining the diagnosis in older children. The MYOD1 p.L122R variant seems to be associated with more aggressive disease, and may be increasingly used in risk stratification with intensification of treatment.

Methods/Case Report

A digital droplet PCR (ddPCR) assay was used to detect the MYOD1 p.L122R in DNA samples with RMS. Patients and controls were coded as positive or negative, and tested for association with clinical features and outcome.

Results (if a Case Study enter NA)

Known-positive cohort of samples was limited by the extreme rarity of this tumor. “Known-positive” status was established by confirmation of the variant with an external clinically-validated assay. The six known positive samples were assessed by ddPCR for the presence of MYOD1 L122R. The L122R variant was detected in all six variants for a sensitivity of 100%. DNA and/or TNA obtained from known wild-type FFPE and frozen material was assessed, for a total of nine unique samples (1 synthetic, 8 patient-derived). All 9 samples were wild- type, with no positive droplets detected, for a specificity of 100%.

Conclusion

Our MYOD1 c.365G&gt;T, p.L122R variant detection by droplet digital PCR (ddPCR) assay is a robust, reproducible, specific and sensitive method to detect the MYOD1 hotspot mutation.

Carbapenem-resistant Enterobacterales colonization and subsequent infection in a neonatal intensive care unit in Shanghai, China

Background

Colonization has been reported to play an important role in carbapenem-resistant Enterobacterales (CRE) infection; however, the extent to which carriers develop clinical CRE infection and related risk factors in neonatal intensive care unit (NICU) patients is unclear.

Aim

To investigate the frequency of CRE colonization and its contribution to infections in NICU patients.

Methods

CRE colonization screening and CRE infection surveillance were performed in the NICU in 2017 and 2018.

Findings

Among 1230 unique NICU patients who were screened for CRE colonization, 144 patients tested positive (11.7%, 144/1230), with 9.2% (110/1197) in the intestinal tract, which was higher than that in the upper respiratory tract (6.6%, 62/945) (P=0.026). Gestational age, low birth weight and prolonged hospitalization were risk factors for CRE colonization (all P<0.001). Diversilab homology monitoring found an overall 17.4% (25/144) risk of infection among patients colonized with CRE. For carbapenem-resistant Klebsiella pneumoniae (CR-KP) and carbapenem-resistant Escherichia coli (CR-ECO), the risks were 19.1% (21/110) and 13.8% (4/29), respectively. The independent risk factors for CR-KP clinical infection among CR-KP carriers were receiving mechanical ventilation (odds ratio (OR), 10.177; 95% confidence interval (CI), 2.667–38.830; P=0.013), a high level of neonatal nutritional risk assessment (OR, 0.251; 95% CI, 0.072–0.881; P=0.031) and a high neonatal acute physiology II (SNAP-II) score (OR, 0.256; 95% CI, 0.882–1.034; P=0.025).

Conclusions

The colonization of CRE may increase the incidence of corresponding CRE infection in NICU patients. Receiving mechanical ventilation, malnutrition and critical conditions with high SNAP-II scores were independent risk factors for subsequent CR-KP clinical infection.

Superconducting Phase Induced by a Local Structure Transition in Amorphous Sb_{2}Se_{3} under High Pressure

Superconductivity and Anderson localization represent two extreme cases of electronic behavior in solids. Surprisingly, these two competing scenarios can occur in the same quantum system, e.g., in an amorphous superconductor. Although the disorder-driven quantum phase transition has attracted much attention, its structural origins remain elusive. Here, we discovered an unambiguous correlation between superconductivity and density in amorphous Sb_{2}Se_{3} at high pressure. Superconductivity first emerges in the high-density amorphous (HDA) phase at about 24 GPa, where the density of glass unexpectedly exceeds its crystalline counterpart, and then shows an enhanced critical temperature when pressure induces crystallization at 51 GPa. Ab initio simulations reveal that the bcc-like local geometry motifs form in the HDA phase, arising from distinct "metavalent bonds." Our results demonstrate that HDA phase is critical for the incipient superconductive behavior.

Single-digit Salmonella detection with the naked eye using bio-barcode immunoassay coupled with recombinase polymerase amplification and a CRISPR-Cas12a system

The ability to visually detect low numbers of Salmonella in food samples is highly valuable but remains a challenge. Here we present a novel platform for ultrasensitive and visual detection of Salmonella Typhimurium by integrating the bio-barcode immunoassay (BCA), recombinase polymerase amplification (RPA), and CRISPR-Cas12a cleavage in a single reaction system (termed as BCA-RPA-Cas12a). In the system, the target bacteria were separated by immunomagnetic nanoparticles and labeled with numerous barcode AuNPs, which carry abundant bio-barcode DNA molecules to amplify the signal. Afterwards, the bio-barcode DNA molecules were amplified by RPA and subsequently triggered the cleavage activity of Cas12a to generate the fluorescence signal. Due to this triplex signal amplification, the BCA-RPA-Cas12a system can selectively detect Salmonella Typhimurium at the single-digit level with the naked eye under blue light within 60 min. Meanwhile, this novel platform was successfully applied to detect Salmonella Typhimurium in spiked milk samples with a similar sensitivity and satisfactory recovery, indicating its potential application in real samples. Furthermore, in virtue of the versatility of the antibody in the stage of BCA, the BCA-RPA-Cas12a system can be extended to further application in other bacteria detection and food safety monitoring.