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Whether metagenomic next-generation sequencing (mNGS) could benefit patients with suspected severe central nervous system (CNS) infection in terms of diagnosis and antibiotic treatment remains unknown. We retrospectively analyzed 79 patients with suspected CNS infection and undertook mNGS. The value of mNGS was investigated in terms of identification of pathogen and guidance for the adjustment of antibiotic treatment. The relationship between the time of initiating mNGS since onset and the Glasgow Outcome Scale (GOS) score after 90-day follow-up were analyzed. Fifty out of 79 cases with suspicious severe CNS infection were finally diagnosed. Despite previous routine laboratory tests, mNGS further promoted the accurate identification of pathogens in 23 cases (47.9%). The sensitivity, specificity, and accuracy of mNGS test in this study were 84.0, 79.3, and 82.3%, respectively. Furthermore, mNGS facilitated the adjustment of empirical antibiotic treatments in 38 cases (48.1%). The time of taking mNGS since onset had an insignificant weak positive correlation with GOS after 90-day follow-up (r = −0.73, P = 0.08). mNGS facilitated the accurate identification of pathogens in suspicious severe CNS infections and promoted the accurate antibiotic therapy even empirical antibiotics were administrated. It should be taken as early as possible to improve the clinical outcome of patients with suspicious severe CNS infection.

One iron compound {[Fe(bipy)3]2(SO3)(OH)4}·14H2O (1) (bipy = 2,2'-bipyridine) has been obtained from a hydrothermal reaction and structurally characterized by single-crystal X-ray diffraction. Compound 1 is characterized by an isolated (0D) structure and the iron center is coordinated by six nitrogen atoms of three bipy molecules to yield an octahedron. Photoluminescence investigation shows that compound 1 displays an emission in the green region. Time-dependent density functional theory (TDDFT) calculation reveals that the photoluminescent emission can be assigned to the ligand-to-metal charge transfer (LMCT) (from the HOMO of the bipy to the LUMO of the iron). Solid-state diffuse reflectance spectra discover that compound 1 features a narrow optical band gap of 1.82 eV, indicating that it is a potential narrow band gap semiconductor. One iron compound has been obtained from a hydrothermal reaction and characterized by single-crystal X-ray diffraction. It features an isolated structure. It displays a photoluminescence emission in the green region which can be assigned to LMCT. It features a narrow optical band gap of 1.82 eV, indicating that it is a potential narrow band gap semiconductor. [ABSTRACT FROM AUTHOR]

Objectives: This comprehensive review aimed to compile cases of patients with thymoma diagnosed with both autoimmune encephalitis (AE) and myasthenia gravis (MG), and describe their clinical characteristics. Methods: Clinical records of 3 AE patients in the first affiliated hospital of Sun Yat‐sen University were reviewed. All of them were diagnosed with AE between 1 November 2021 and 1 March 2022, and clinical evidence about thymoma and MG was found. All published case reports were searched for comprehensive literature from January 1990 to June 2022. Results: A total of 18 cases diagnosed with thymoma‐associated autoimmune encephalitis (TAAE) and thymoma‐associated myasthenia gravis (TAMG) were included in this complication, wherein 3 cases were in the first affiliated hospital of Sun Yat‐sen University and the other 15 were published case reports. 5/18 patients had alpha‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid receptor antibody (AMPAR‐Ab) in their serum and cerebrospinal fluid (CSF). All of them had positive anti‐acetylcholine receptor antibody (AChR‐Ab). And 12/18 patients showed a positive response to thymectomy and immunotherapy. Besides, thymoma recurrences were detected because of AE onset. And the shortest interval between operation and AE onset was 2 years in patients with thymoma recurrence. Conclusions: There was no significant difference in the clinical manifestations between these patients and others with only TAMG or TAAE. TAAE was commonly associated with AMPAR2‐Ab. Significantly, AE more commonly heralded thymoma recurrences than MG onset. And the intervals of thymectomy and MG or AE onset had different meanings for thymoma recurrence and prognoses of patients. [ABSTRACT FROM AUTHOR]

A two-dimensional ultrafast X-ray imager (UXI) composed of a time-dilation device, an electron-beam imaging unit, a gated microchannel plate (MCP) framing tube, and a pulser was developed. The time-dilation device extends the time spread of the electron signal generated by the pulsed photocathode (PC), and the electron-beam imaging unit images the electron pulse from PC to MCP. Finally, the gated MCP framing tube samples the dilated electron pulse. The time resolution and image size of the UXI were measured with an X-ray generated by a terawatt laser targeting device. When a driving pulse with a 2 V/ps slope is applied to the PC, the measured time resolution is 21 ps, and the image size is 12 mm × 3.9 mm. Furthermore, the image size varies with the time resolution. The results show that as the time resolution improves, the image size decreases. The use of two opposite-transmission PC driving pulses could improve the image size. Moreover, the measured UXI spatial resolution is 5 lp/mm, and the spatial resolution will be worse with the increasing off-axis distance. [ABSTRACT FROM AUTHOR]

To take advantage of the high aspect ratio of cellulose nanofibrils (CNFs) and high performance luminescence of carbon dots (CDs), a novel fluorescent nanocellulosic hydrogel was synthesised and used not only as an effective adsorbent for the removal of heavy metals, but also as an optical sensor for the detection of heavy metals. This fluorescent nanocellulosic hydrogel was characterized with respect to its morphological features, chemical composition and optical properties by means of optical microscopy, SEM, XRD, FTIR, UV-vis and fluorescence spectroscopy. The effects of contact time and initial concentration on the adsorption performance of the nanocellulosic hydrogel were investigated. Based on the experimental results, the maximum adsorption capacities for Fe3+, Ba2+, Pb2+ and Cu2+ were 769, 212, 2056 and 1246 mg g−1, respectively. The prepared fluorescent nanocellulosic hydrogel demonstrated strong blue fluorescence with a fluorescence quantum yield of 23.6%, and displayed high sensitivity for the detection of Fe3+. In this hydrogel, the CNFs modified with CDs not only facilitated hydroxyl-induced aggregation of heavy metals as the adsorption-aggregator, but also allowed a rapid visual response to heavy metals as the optical sensor, which increased the adsorption capacity of heavy metals, and improved the stability of the fluorescence signal and the sensitivity for determining the concentration of heavy metals. [ABSTRACT FROM AUTHOR]

Quantitative fluorescence polymerase chain reaction (QF-PCR) may be used as a mid-pregnancy test to confirm the diagnosis of common fetal aneuploidies, but its use is controversial. The present study aimed to determine the value of QF-PCR for diagnostic confirmation of karyotyping and the impact of parental origin and meiosis stage on the detected aneuploidy. The present prospective cohort study included pregnant women (age, 21–45 years; gestational age, 17–25 weeks) who consulted between May 2015 and December 2016. Women were screened and only consecutive high-risk individuals were included (n=428). QF-PCR analysis of amniocytes was performed. Karyotype analysis was considered the gold standard. Parental karyotyping was performed if the embryo exhibited any aneuploidy. GeneMapper 3.2 was used for data analysis. There were no false-negative or false-positive QF-PCR results, with 100% concordance with the karyotype. The aneuploidy distribution (n=105) was 68.6% for trisomy 21, 19.0% for trisomy 18, 7.6% for sex chromosome aneuploidy, 3.8% for trisomy 13 and 1.0% for 48,XXX,+18. Regarding trisomy 21, most cases (86.1%) were of maternal origin, 8.3% paternal and 6.5% undefined. Trisomy 18 was 88.2% maternal and 11.8% paternal. Maternal meiosis stage errors in trisomy 21 mainly occurred in meiosis I, while the origin of trisomy 18 exhibited similar proportions between meiosis I and II. The combination of non-invasive pre-natal testing and QF-PCR may become a rapid and effective method for fetal aneuploidy detection. QF-PCR may provide more genetic information for clinical diagnosis and treatment than karyotyping alone. [ABSTRACT FROM AUTHOR]

For clean, effective, and high value-added use of wood, a novel non-toxic fluorescent molecularly imprinted hydrogel (FMIH) was prepared based on wood-derived cellulose nanocrystals and carbon dots for efficient sorption and sensitive detection of tetracycline (TC). The FMIH's morphology, chemical structure, optical properties and non-cytotoxicity were investigated. The adsorption performance of FMIH toward TC was studied, indicating that the sorption data were well fitted by the Langmuir and Pseudo-second-order models, and the maximum sorption capacity was 544.4 mg/g. An evaluation of the detection performance of FMIH toward TC showed its excellent selectivity and sensitivity to TC with the detection limit of 0.11 μg/L. Mechanism analysis confirmed that the efficient sorption and sensitive detection was due to specific molecular recognition sites introduced by wood-derived cellulose nanocrystals and carbon dots. Moreover, a cost analysis performed for FMIH and commercial activated carbon (CAC) showed that the cost of removing 1 g of TC using FMIH was almost thirty-four times cheaper than that of CAC. This work could provide a new way for using wood to produce a low-cost, multifunctional, and green adsorbent for removing antibiotics. [Display omitted] • A non-toxic molecularly imprinted hydrogel with good fluorescence property. • The novel hydrogel simultaneously had effective adsorption and detection abilities. • Carbon dots in the 3D porous structure enhanced fluorescent detection sensitivity. • Carbon dots facilitated amino group-induced adsorption of tetracycline. [ABSTRACT FROM AUTHOR]

• A hydrogel with excellent sorption and sensing abilities for Cr(VI) was synthesized. • Carbon dots wrapped into this hydrogel provided a rapid visual response to Cr(VI). • Carbon dots facilitated amino group-induced aggregation of Cr(VI). • The mechanism of Cr(VI) sorption and sensing for this hydrogel was determined. To effectively detect and remove environmentally hazardous Cr(VI), a novel 3D porous fluorescent hydrogel was synthesised using amino-modified carbon dots and cellulose nanofibers. The synthesised fluorescent hydrogel was characterized to determine its morphology, crystalline structure, chemical composition and optical property using scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, UV–vis absorption spectroscopy and photoluminescence spectroscopy. The sorption properties of the synthesised fluorescent hydrogel were further analyzed. The maximum sorption capacity for Cr(VI) reached 534.4 mg/g, the adsorption isotherm was well fitted using Langmuir model, and the adsorption kinetics were well fitted using a pseudo-second-order model. The sensing ability of the synthesized hydrogel for Cr(VI) was also determined. Furthermore, the mechanism of Cr(VI) sorption and sensing was determined. Accordingly, this novel 3D porous fluorescent hydrogel was identified to be a promising sorbent with advantages of excellent sorption and sensing abilities for environmentally hazardous Cr(VI). [ABSTRACT FROM AUTHOR]

The piezoelectric enhancement of photo‐catalytic activity for water splitting and pollutant degradation is a novel approach to developing renewable energy and environmental protection applications. Herein, a new form of defect engineered Na‐Sm bimetallic‐regulated CaBi2Nb2O9 platelet is synthesized via a molten salt process for water splitting and pollutant degradation applications. An intermediate band structure is introduced by Sm‐doping, and empty orbitals in the conductive band are introduced by Na‐doping. These factors, combined with the increased local charge density around the Sm and Na atoms, result in an increased electrical conductivity, improved electron mobility, and provide additional electrons for enhancing catalytic reactions. As a consequence, the judicious co‐doping of CaBi2Nb2O9 with Sm and Na leads to a unique synergetic piezo‐photo‐electric effect to provide a superior piezo‐photo‐catalytic performance for H2 production (158.53 µmol g−1 h−1) and pollutant degradation (rate constant, k = 0.257 min−1). This new approach provides important insights into the application of defect engineering to exploit the cooperative doping of alkaline earth metals and rare metals to create high‐performance catalysts. [ABSTRACT FROM AUTHOR]

Abstract: Reaction of 2-(1-(pyridin-2-yl)ethyl)propane-1,3-dithiol with tri-iron dodecacarbonyl afforded a diiron pentacarbonyl complex, [Fe2 L(CO)5] (A and H2L =2-methyl-2-(1,2,5,6-tetrahydropyridin-2-yl)propane-1,3-dithiol). In the reaction, the pyridinyl ring of the original ligand was partially hydrogenated during the reaction. This complex was fully characterised by using crystallographic, infrared, and NMR spectroscopic techniques. Formation reaction of its bridging hydride and subsequent conversion into its protonated diiron hexacarbonyl complex, [Fe2 L(CO)6] (ACOH+ in which the N atom of L is decoordinated and protonated), were experimentally and theoretically investigated. Results for this complex alongside with theoretic investigations into other diiron pentacarbonyl analogues revealed positive correlation of basicity of the internal bases of these investigated complexes to bridging hydrides formation. But subsequent conversion of these bridging hydrides into protonated diiron hexacarbonyl complexes was not solely dictated by the basicity. Protophilicity of the internal base and lability of its coordination with the diiron centre play also an important role as revealed by experimental and theoretic investigations. [Copyright &y& Elsevier]

Abstract: Reaction of a trithiol ligand, 2-(mercaptomethyl)-2-methylpropane-1,3-dithiol (H3L), with tri-iron dodecacarbonyl in toluene produces two hexa-iron clusters (1 and 2). The two clusters are characterised crystallographically and spectroscopically. NMR spectroscopy reveals that the cluster 2 exists in two conformations in equilibrium 2 anti ⇔ 2 syn and the equilibrium constant K eq =0.55 under CO atmosphere. In the cluster 2, the central {Fe2S2(CO)6} sub-unit is flanked by two identical {Fe2S2(CO)6} satellite sub-units through thiolate linkages whereas one of the thiolate linkages can further form Fe–S bond with the proximal Fe atom in one of the two satellite sub-units to produce the cluster 1 by expelling one CO. This conversion can be entirely reversed by continuously purging CO through the solution of the cluster 1. As suggested by DFT calculations, the conversion features a key step, the rotation of the Feprox(CO)3 to expose a vacant site for exogenic ligand binding (the S atom from the central sub-unit in this case) with concomitant switch for one of the three CO ligands in the unit of Feprox(CO)3 from terminal to bridging orientation. The conversion from the clusters 1–2 involving one CO uptake is much faster than its reverse process since the latter is an endergonic process characterised by large reaction barriers, as revealed by the DFT calculations. [Copyright &y& Elsevier]

A novel fluorescent lignin-based hydrogel with cellulose nanofibers and carbon dots (CDs) was synthesized for the high-value utilization of lignin and control of hexavalent chromium (Cr(VI)). Its chemical and physical structure was characterized, and its Cr(VI) sorption performance was evaluated. The results demonstrated that 3D porous structures were constructed in this hydrogel. The maximum adsorption capacity of this hydrogel was 599.9 mg/g, and its sorption performance met Freundlich and pseudo-second-order models. Meanwhile, this novel hydrogel exhibited high sensitivity to Cr(VI), with a limit of detection of 11.2 mg/L and a wide linear range from 15 to 200 mg/L. Moreover, its mechanism for efficiently adsorbing and detecting Cr(VI) was analyzed. The results confirmed that the efficient adsorption and detection were due to these 3D porous structures generated by the lignin and cellulose nanofibers modified with CDs. The porous structures provided many active sites and ion transport channels, thereby improving the adsorption, and stabilized the fluorescence signal, thus enhancing the detection. Unlabelled Image • A lignin-based hydrogel for sorption and detection of Cr(VI) was prepared. • Carbon dots fixed to this hydrogel provided a rapid response to Cr(VI). • The mechanism of efficient adsorption and detection of Cr(VI) was analyzed. [ABSTRACT FROM AUTHOR]