Bifunctional enzyme-mimicking metal-organic frameworks for sensitive acetylcholine analysis.

The development of nanomaterials with multi-enzyme-like activity is crucial for addressing challenges in multi-enzyme-based biosensing systems, including cross-talk between different enzymes and the complexities and costs associated with detection. In this study, Pt nanoparticles (Pt NPs) were successfully supported on a Zr-based metal-organic framework (MOF-808) to create a composite catalyst named MOF-808/Pt NPs. This composite catalyst effectively mimics the functions of acetylcholinesterase (AChE) and peroxidase (POD). Leveraging this capability, we replaced AChE and POD with MOF-808/Pt NPs and constructed a biosensor for sensitive detection of acetylcholine (ACh). The MOF-808/Pt NPs catalyze the hydrolysis of ACh, resulting in the production of acetic acid. The subsequent reduction in pH value further enhances the POD-like activity of the MOFs, enabling signal amplification through the oxidation of a colorimetric substrate. This biosensor capitalizes on pH variations during the reaction to modulate the different enzyme-like activities of the MOFs, simplifying the detection process and eliminating cross-talk between different enzymes. The developed biosensor holds great promise for clinical diagnostic analysis and offers significant application value in the field.

Temporal and spatial variations in the sub-daily precipitation structure over the Qinghai-Tibet Plateau (QTP).

Precipitation is a vital component of the global atmospheric and hydrological cycles and influencing the distribution of water resources. Even subtle changes in precipitation can significantly impact ecosystems, energy cycles, agricultural production, and food security. Therefore, understanding the changes in the precipitation structure under climate change is essential. The Qinghai-Tibet Plateau (QTP) is a region sensitive to global climate change and profoundly impacts the atmospheric water cycle in Asia and even globally, rendering it a hot topic in climate change research in recent years. Few studies have examined on the sub-daily scale precipitation structure over the QTP. In this paper, the characteristics of sub-daily precipitation on the QTP were systematically investigated from multiple perspectives, including the concentration index, skewness (the third standardized moment of a distribution), and kurtosis (the fourth standardized moment of a distribution). The results indicated that the frequency of moderate-intensity nighttime precipitation on the QTP generally increased, and the analysis of both the concentration index and kurtosis (skewness) suggested that extreme precipitation was more frequent in the southwestern foothills of the QTP. Furthermore, potential high-risk areas for natural disasters were identified on the QTP, and found that the southeastern part of the plateau constituted a potential hotspot area for flood disasters. Given the complexity of climate change, a comprehensive analysis of the spatiotemporal characteristics of diurnal and nighttime precipitation changes on the QTP could help reveal the regularity of precipitation changes. This has significant implications for forecasting, warning, disaster preparedness, and mitigation efforts on the QTP.

A general large-scale synthesis approach for crystalline porous materials.

Crystalline porous materials such as covalent organic frameworks (COFs), metal-organic frameworks (MOFs) and porous organic cages (POCs) have been widely applied in various fields with outstanding performances. However, the lack of general and effective methodology for large-scale production limits their further industrial applications. In this work, we developed a general approach comprising high pressure homogenization (HPH), which can realize large-scale synthesis of crystalline porous materials including COFs, MOFs, and POCs under benign conditions. This universal strategy, as illustrated in the proof of principle studies, has prepared 4 COFs, 4 MOFs, and 2 POCs. It can circumvent some drawbacks of existing approaches including low yield, high energy consumption, low efficiency, weak mass/thermal transfer, tedious procedures, poor reproducibility, and high cost. On the basis of this approach, an industrial homogenizer can produce 0.96 ~ 580.48 ton of high-performance COFs, MOFs, and POCs per day, which is unachievable via other methods.

Small-Molecule Probe-Induced In Situ-Sensitized Photoelectrochemical Biosensor for Monitoring α-Glucosidase Activity.

Semiconductor-based photoelectrochemical (PEC) biosensors have garnered significant attention in the field of disease diagnosis and treatment. However, the recognition units of these biosensors are mainly limited to bioactive macromolecules, which hinder the photoelectric response due to their insulating characteristics. In this study, we develop an in situ-sensitized strategy that utilizes a small-molecule probe at the interface of the photoelectrode to accurately detect α-glucosidase (α-Glu) activity. Silane, a prototype small-molecule probe, was surface-modified on graphitic carbon nitride to generate Si nanoparticles upon reacting with hydroquinone, the enzymatic product of α-Glu. The in situ formed heterojunction enhances the light-harvesting property and photoexcited carrier separation efficiency. As a result, the in situ-sensitized PEC biosensor demonstrates excellent accuracy, a low detection limit, and outstanding anti-interference ability, showing good applicability in evaluating α-Glu activity and its inhibitors in human serum samples. This novel in situ sensitization approach using small-molecule probes opens up new avenues for developing simple and efficient PEC biosensing platforms by replacing conventional biorecognition elements.

Aberrant hyper-expression of the RNA binding protein GIGYF2 in endothelial cells modulates vascular aging and function.

Vascular endothelial cells (ECs) senescence plays a crucial role in vascular aging that promotes the initiation and progression of cardiovascular disease. The mutation of Grb10-interacting GYF protein 2 (GIGYF2) is strongly associated with the pathogenesis of aging-related diseases, whereas its role in regulating ECs senescence and dysfunction still remains elusive. In this study, we found aberrant hyperexpression of GIGYF2 in senescent human ECs and aortas of old mice. Silencing GIGYF2 in senescent ECs suppressed eNOS-uncoupling, senescence, and endothelial dysfunction. Conversely, in nonsenescent cells, overexpressing GIGYF2 promoted eNOS-uncoupling, cellular senescence, endothelial dysfunction, and activation of the mTORC1-SK61 pathway, which were ablated by rapamycin or antioxidant N-Acetyl-l-cysteine (NAC). Transcriptome analysis revealed that staufen double-stranded RNA binding protein 1 (STAU1) is remarkably downregulated in the GIGYF2-depleted ECs. STAU1 depletion significantly attenuated GIGYF2-induced cellular senescence, dysfunction, and inflammation in young ECs. Furthermore, we disclosed that GIGYF2 acting as an RNA binding protein (RBP) enhances STAU1 mRNA stability, and that the intron region of the late endosomal/lysosomal adaptor MAPK and mTOR activator 4 (LAMTOR4) could bind to STAU1 protein to upregulate LAMTOR4 expression. Immunofluorescence staining showed that GIGYF2 overexpression promoted the translocation of mTORC1 to lysosome. In the mice model, GIGYF2flox/flox Cdh-Cre+ mice protected aged mice from aging-associated vascular endothelium-dependent relaxation and arterial stiffness. Our work discloses that GIGYF2 serving as an RBP enhances the mRNA stability of STAU1 that upregulates LAMTOR4 expression through binding with its intron region, which activates the mTORC1-S6K1 signaling via recruitment of mTORC1 to the lysosomal membrane, ultimately leading to ECs senescence, dysfunction, and vascular aging. Disrupting the GIGYF2-STAU1-mTORC1 signaling cascade may represent a promising therapeutic approach against vascular aging and aging-related cardiovascular diseases.

Engineering the microenvironment of electron transport layers with nickle single-atom sites for boosting photoelectrochemical performance.

Advances in the rational design of semiconductor-electrocatalyst photoelectrodes provide robust driving forces for improving energy conversion and quantitative analysis, while a deep understanding of elementary processes remains underwhelming due to the multistage interfaces involved in semiconductor/electrocatalyst/electrolyte. To address this bottleneck, we have constructed carbon-supported nickel single atoms (Ni SA@C) as an original electron transport layer with catalytic sites of Ni-N4 and Ni-N2O2. This approach illustrates the combined effect of photogenerated electron extraction and the surface electron escape ability of the electrocatalyst layer in the photocathode system. Theoretical and experimental studies reveal that Ni-N4@C, with excellent oxygen reduction reaction catalytic activity, is more beneficial for alleviating surface charge accumulation and facilitating electrode-electrolyte interfacial electron-injection efficiency under a similar built-in electric field. This instructive method enables us to engineer the microenvironment of the charge transport layer for steering the interfacial charge extract and reaction kinetics, providing a great prospect for atomic scale materials to enhance photoelectrochemical performance.

A binary composite La(OH)3@Ni(OH)2 nanomaterial on carboxyl graphene for an efficient hybrid supercapacitor electrode.

In this work, we present a binary composite of La(OH)3@Ni(OH)2 on carboxyl graphene (La@Ni/CG) as an electrode material. The layered La@Ni/CG double hydroxides (LDHs) were synthesized by a simple electrodeposition method in which La(OH)3 nanoparticles were first adsorbed onto carboxyl graphene and then coated with Ni(OH)2, with different particle shapes due to the large pH change near the cathodic region. Scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) were used to characterise the as-prepared La@Ni/CG composite. These results showed that the La@Ni/CG composite exhibited improved electrochemical properties, including large specific capacitance (1334.7 F g-1 at 1.4 A g-1) and capacity retention of 90.6% even after 3000 cycles, and excellent rate capability. The improved electrochemical performance of the composite can be attributed to the synergistic effect of surface adsorption and conductive pathways provided by the multiple active species (Ni, La and C) in the La@Ni/CG composite. The results presented in this work provide advances in the efficient design of nanomaterial based electrochemical energy storage devices.

Improving Interface Matching in MOF-on-MOF S-Scheme Heterojunction through π-π Conjugation for Boosting Photoelectric Response.

Accelerating the migration of interfacial carriers in a heterojunction is of paramount importance for driving high-performance photoelectric responses. However, the inferior contact area and large resistance at the interface limit the eventual photoelectric performance. Herein, we fabricated an S-scheme heterojunction involving a 2D/2D dual-metalloporphyrin metal-organic framework with metal-center-regulated CuTCPP(Cu)/CuTCPP(Fe) through electrostatic self-assembly. The ultrathin nanosheet-like architectures reduce the carrier migration distance, while the similar porphyrin backbones promote reasonable interface matching through π-π conjugation, thereby inhibiting the recombination of photogenerated carriers. Furthermore, the metal-center-regulated S-scheme band alignments create a giant built-in electric field, which provides a huge driving force for efficient carrier separation and migration. Coupling with the biomimetic catalytic activity of CuTCPP(Fe), the resultant heterojunction was utilized to construct photoelectrochemical uric acid biosensors. This work provides a general strategy to enhance photoelectric responses by engineering the interfacial structure of heterojunctions.

Horseradish Peroxidase Immobilized in Metal Aerogels Boosts Electron Transfer and an Interfacial Reaction for Photoelectrochemical Immunoassay.

Photoelectrochemical (PEC) enzymatic biosensors have attracted widespread attention for their specificity and sensitivity, but the charge migration between an enzyme and a semiconductor remains uncertain. In this work, horseradish peroxidase (HRP) was successfully immobilized on ionic liquid-functioned Cu@Cu2O (IL-Cu@Cu2O) aerogels to boost charge transfer and an interfacial redox reaction. The photogenerated electrons flow from the conduction band of Cu2O to HRP under the assistance of Cu and are subsequently captured by [Fe(CN)6]3- in the electrolyte, which boosts the PEC response. The improved interfacial catalytic ability after the immobilization of HRP is proved by the enhanced redox ability under light irradiation. Benefiting from the excellent PEC activity and catalysis reaction of IL-Cu@Cu2O@HRP, an immunoassay platform was constructed for sensing prostate-specific antigens, which presents a wide detection range and a low limit of detection. An in-depth understanding of the direct electronic communication between a photoactive material and an enzyme for boosted charge transfer and interfacial catalysis provides a new view for the design of advanced PEC sensing platforms.

Yellow Carbon Dots for Fluorescent Water Sensing, Relative Humidity Sensing, and Anticounterfeiting Applications.

Most fluorescent probes based on carbon dots (CDs) fluorescence color or intensity change are still used for detection in solution, but in practical fluorescence detection applications, detection in the solid state is necessary. Therefore, a CDs-based fluorescence sensing device is designed in this paper, which can be used for water detection in liquid and solid states. Using oPD as a single precursor, yellow fluorescent CDs (y-CDs) were prepared by hydrothermal method, which can be used in the field of water detection and anti-counterfeiting by using its solvent-sensitive properties. First, y-CDs can be used to visually and intelligently detect the water content in ethanol. Secondly, it can be used to detect the Relative Humidity (RH) of the environment by combining it with cellulose to form a fluorescent film. Finally, y-CDs can also be used as a fluorescent material for fluorescence anti-counterfeiting.

Relationship of the levels of reactive oxygen species in the fertilization medium with the outcome of in vitro fertilization following brief incubation.

Embryo selection in in vitro fertilization-embryo transfer (IVF-ET) mostly relies on morphological assessment using a conventional microscope or the time-lapse monitoring system, which is not comprehensive. Inappropriate levels of reactive oxygen species (ROS) in the fertilization medium may cause damage to gametes, eventually leading to adverse IVF outcomes. The present study aimed to identify the optimal oxidation-reduction level in the fertilization medium for IVF outcomes by measuring the static oxidation-reduction potential (sORP) using a highly accurate and sensitive MiOXSYS system. A total of 136 patients undergoing IVF following brief incubation were divided equally into 4 groups in this prospective cohort study. The sORP value in the fertilization medium was detected using the MiOXSYS system, and its relationship with IVF outcomes was analyzed. The primary outcome was pregnancy outcomes, including live birth rate (LBR), clinical pregnancy rate (CPR), biochemical pregnancy rate (BPR), and implantation rate (IR). The secondary outcome was embryo quality, including fertilization rate (FR), cleavage rate (CR), available embryo rate (AER), and good-quality embryo rate (GQER). Group II (sORP: 228.7-235.3 mV) showed a higher LBR, CPR, BPR, and IR compared with Group III (sORP: 235.4-242.7 mV), presented as follows: LBR (32.0% for Group II vs 3.6% for Group III, P = 0.033), CPR (32.0% for Group II vs 3.6% for Group III, P = 0.033), BPR (36.0% for Group II vs 3.6% for Group III, P = 0.019), and IR (31.3% for Group II vs 2.7% for Group III, P = 0.003). The FR in Groups I and II had lower significant differences compared with that in Groups III and IV (71.7% and 70.3% for Groups I and II vs 83.5% and 80.4% for Groups III and IV, P = 0.000). The GQER in Group I to Group IV was 32.7%, 37.4%, 26.5%, and 33.3%, respectively (P = 0.056). This study indicated that the sORP value in the fertilization medium might be a potential indicator of embryo quality and pregnancy outcome.

Nickel Single-Atom Catalyst-Mediated Efficient Redox Cycle Enables Self-Checking Photoelectrochemical Biosensing with Dual Photocurrent Readouts.

Developing a self-checking photoelectrochemical biosensor with dual photocurrent signals could efficiently eliminate false-positive or false-negative signals. Herein, a novel biosensor with dual photocurrent responses was established for the detection of acetylcholinesterase activity. To achieve photocurrent polarity-switchable behavior, the iodide/tri-iodide redox couple was innovatively introduced to simultaneously consume the photoexcited electrons and holes, which circumvents the inconvenience caused by the addition of different hole- and electron-trapping agents in the electrolyte. Importantly, benefiting from the high catalytic activity, the enhanced photoelectric responsivity can be realized after decorating the counter electrode with nickel single-atom catalysts, which promotes a more efficient iodide/tri-iodide redox reaction under low applied voltages. It is envisioned that the proposed photocurrent polarity switching system offers new routes to sensitive and reliable biosensing.

Intelligent depression detection with asynchronous federated optimization.

The growth of population and the various intensive life pressures everyday deepen the competitions among people. Tens of millions of people each year suffer from depression and only a fraction receives adequate treatment. The development of social networks such as Facebook, Twitter, Weibo, and QQ provides more convenient communication and provides a new emotional vent window. People communicate with their friends, sharing their opinions, and shooting videos to reflect their feelings. It provides an opportunity to detect depression in social networks. Although depression detection using social networks has reflected the established connectivity across users, fewer researchers consider the data security and privacy-preserving schemes. Therefore, we advocate the federated learning technique as an efficient and scalable method, where it enables the handling of a massive number of edge devices in parallel. In this study, we conduct the depression analysis on the basis of an online microblog called Weibo. A novel algorithm termed as CNN Asynchronous Federated optimization (CAFed) is proposed based on federated learning to improve the communication cost and convergence rate. It is shown that our proposed method can effectively protect users' privacy under the premise of ensuring the accuracy of prediction. The proposed method converges faster than the Federated Averaging (FedAvg) for non-convex problems. Federated learning techniques can identify quality solutions of mental health problems among Weibo users.

Mechanism of METTL14 and m6A modification of lncRNA MALAT1 in the proliferation of oral squamous cell carcinoma cells.

OBJECTIVES: Methyltransferase-like 14 (METTL14) plays an epigenetic role in various cancer through N6-methyladenosine (m6A) modification. This study sought to analyze the mechanism of METTL14 in oral squamous cell carcinoma (OSCC) cell proliferation. METHODS: Expression levels of METTL14, lncRNA metastasis associated with lung adenocarcinoma transcript 1 (lncRNA MALAT1), microRNA (miR)-224-5p, and histone lysine demethylase 2A (KDM2A) in OSCC tissues (N = 40), and cell lines (FaDu, SCC-25, CAL-27, and SCC-15) were detected. Cell viability and colony formation capacity were assessed. m6A level, stability, and subcellular localization of lncRNA MALAT1 were determined. Nude mouse xenograft tumor assay was performed to confirm the role of METTL14 in vivo. RESULTS: METTL14 and lncRNA MALAT1 were upregulated, and miR-224-5p was downregulated in OSCC tissues and cells. Silencing METTL14 repressed OSCC cell viability and colony formation. Overexpression of MALAT1 and KDM2A or miR-224-5p downregulation reversed the inhibition of silencing METTL14 on OSCC cell proliferation. METTL14 induced m6A modification of MALAT1 to upregulate MALAT1. MALAT1 is comparatively bound to miR-224-5p to promote KDM2A transcription. In vivo, METTL14 promoted tumor growth via regulating MALAT1/miR-224-5p/ KDM2A. CONCLUSIONS: Overall, our findings verified the therapeutic role of silencing METTL14 in OSCC treatment through the MALAT1/miR-224-5p/KDM2A axis.

Establishment and validation of novel MRI radiomic feature-based prognostic models to predict progression-free survival in locally advanced rectal cancer.

In locally advanced rectal cancer (LARC), an improved ability to predict prognosis before and after treatment is needed for individualized treatment. We aimed to utilize pre- and post-treatment clinical predictors and baseline magnetic resonance imaging (MRI) radiomic features for establishing prognostic models to predict progression-free survival (PFS) in patients with LARC. Patients with LARC diagnosed between March 2014 and May 2016 were included in this retrospective study. A radiomic signature based on extracted MRI features and clinical prognostic models based on clinical features were constructed in the training cohort to predict 3-year PFS. C-indices were used to evaluate the predictive accuracies of the radiomic signature, clinical prognostic models, and integrated prognostic model (iPostM). In total, 166 consecutive patients were included (110 vs. 56 for training vs. validation). Eleven radiomic features were filtered out to construct the radiomic signature, which was significantly related to PFS. The MRI feature-derived radiomic signature exhibited better prognostic performance than the clinical prognostic models (P = 0.007 vs. 0.077). Then, we proposed an iPostM that combined the radiomic signature with tumor regression grade. The iPostM achieved the highest C-indices in the training and validation cohorts (0.942 and 0.752, respectively), outperforming other models in predicting PFS (all P < 0.05). Decision curve analysis and survival curves of the validation cohort verified that iPostM demonstrated the best performance and facilitated risk stratification. Therefore, iPostM provided the most reliable prognostic prediction for PFS in patients with LARC.

Anlotinib combined with chemotherapy and immunotherapy for advanced pulmonary sarcomatoid cancer: a case report and literature review.

Background: Pulmonary sarcomatoid carcinoma (PSC) is a rare disease which is highly malignant with a poor prognosis. PSC is highly resistant to chemotherapy and radiotherapy and is prone to recurrence even after surgery. Most of what is known about PSC comes from limited single-center, retrospective studies. There is still no standard international clinical guideline for PSC. Limited case reports have shown that PSC patients with driver gene mutations and high programmed death-ligand 1 (PD-L1) expression have good responses to molecular targeted therapy and immune checkpoint inhibitor (ICI) immunotherapy, respectively. Therefore, current first-line chemotherapy, targeted therapy and immunotherapy play a leading role in the diagnosis and treatment of advanced PSC patients. Case Description: We report a 42-year-old male who was diagnosed with PSC [stage IVB (T4N2M1)] and treated at our department (Department of Radiation Oncology, The Affiliated Hospital of Soochow University). The initial computed tomography (CT) scan of the chest showed a large mass (159 mm × 112 mm) which on needle biopsy showed sarcomatoid carcinoma histology. The patient received 8 cycles of abraxane plus cisplatin chemotherapy combined with anlotinib and immunotherapy, followed by immunotherapy and anlotinib for >1 year. Finally, the local tumor was well controlled, and no obvious drug-related adverse reactions were observed. The large lesions in the lung remained in complete response for >24 months. Conclusions: To our knowledge, this is the first reported case of an advanced PSC patient showing a good response to the treatment consisting of anlotinib combined with sintilimab and platinum-doublet chemotherapy. This case suggests that chemotherapy combined with antiangiogenic therapy and immunotherapy may benefit patients with advanced PSC. Long-term immunotherapy and anlotinib maintenance therapy has been safe and effective in our case. However, randomized controlled clinical studies are needed to confirm the efficacy and safety of these treatment options.

Ultra-Low Content Bismuth-Anchored Gold Aerogels with Plasmon Property for Enhanced Nonenzymatic Electrochemical Glucose Sensing.

Effective glucose surveillance provides a strong guarantee for the high-quality development of human health. Au nanomaterials possess compelling applications in nonenzymatic electrochemical glucose biosensors owing to superior catalytic performances and intriguing biocompatibility properties. However, it has been a grand challenge to accurately control the architecture and composition of Au nanomaterials to optimize their optical, electronic, and magnetic properties for further improving the performance of electrocatalytic sensing. Herein, ultra-low content Bi-anchored Au aerogels are synthesized via a one-step reduction strategy. Benefiting from the unique structure of aerogels as well as the synergistic effect between Au and Bi, the optimized Au200Bi aerogels greatly boost the activity of glucose oxidation compared with Au aerogels. Under plasmon resonance excitation, bimetallic Au200Bi aerogels with wider photics-dependent properties further show plasmon-promoted glucose electro-oxidation activity, which is derived from the photothermal and photoelectric effects caused by the local surface plasmon resonance. Thanks to the enhanced performance, a nonenzymatic electrochemical glucose biosensor is constructed to detect glucose with high sensitivity. This plasmon-promoted electrocatalytic activity through the synergetic strategy of bimetallic aerogels has potential applications in various research fields.

Whole-Genome Sequencing for Resistance Level Prediction in Multidrug-Resistant Tuberculosis.

Defining the precise relationship between resistance mutations and quantitative phenotypic drug susceptibility testing will increase the value of whole-genome sequencing (WGS) for predicting tuberculosis drug resistance. However, a large number of WGS data sets currently lack corresponding quantitative phenotypic data-the MICs. Using MYCOTBI plates, we determined the MICs to nine antituberculosis drugs for 154 clinical multidrug-resistant tuberculosis isolates from the Shenzhen Center for Chronic Disease Control in Shenzhen, China. Comparing MICs with predicted drug-resistance profiles inferred by WGS showed that WGS could predict the levels of resistance to isoniazid, rifampicin, streptomycin, fluoroquinolones, and aminoglycosides. We also found some mutations that may not be associated with drug resistance, such as EmbB D328G, mutations in the gid gene, and C-12T in the eis promoter. However, some strains carrying the same mutations showed different levels of resistance to the corresponding drugs. The MICs of different strains with the RpsL K88R, fabG1 C-15T mutations and some with mutations in embB and rpoB, had MICs to the corresponding drugs that varied by 8-fold or more. This variation is unexplained but could be influenced by the bacterial genetic background. Additionally, we found that 32.3% of rifampicin-resistant isolates were rifabutin-susceptible, particularly those with rpoB mutations H445D, H445L, H445S, D435V, D435F, L452P, S441Q, and S441V. Studying the influence of bacterial genetic background on the MIC and the relationship between rifampicin-resistant mutations and rifabutin resistance levels should improve the ability of WGS to guide the selection of medical treatment regimens. IMPORTANCE Whole-genome sequencing (WGS) has excellent potential in drug-resistance prediction. The MICs are essential indications of adding a particular antituberculosis drug dosage or changing the entire treatment regimen. However, the relationship between many known drug-resistant mutations and MICs is unclear, especially for rarer ones. The results showed that WGS could predict resistance levels to isoniazid, rifampicin, streptomycin, fluoroquinolones, and aminoglycosides. However, some mutations may not be associated with drug resistance, and some others may confer various MICs to strains carrying them. Also, 32.3% of rifampicin (RIF)-resistant strains were classified as sensitive to rifabutin (RFB), and some mutations in the rpoB gene may be associated with this phenotype. Our data on the MIC distribution of strains with some rarer mutations add to the accumulated data on the resistance level associated with such mutations to help guide further research and draw meaningful conclusions.

Chemically Stable Guanidinium Covalent Organic Framework for the Efficient Capture of Low-Concentration Iodine at High Temperatures.

The capture of radioactive I2 vapor from nuclear waste under industrial operating conditions remains a challenging task, as the practical industrial conditions of high temperature (≥150 °C) and low I2 concentration (∼150 ppmv) are unfavorable for I2 adsorption. We report a novel guanidinium-based covalent organic framework (COF), termed TGDM, which can efficiently capture I2 under industrial operating conditions. At 150 °C and 150 ppmv I2, TGDM exhibits an I2 uptake of ∼30 wt %, which is significantly higher than that of the industrial silver-based adsorbents such as Ag@MOR (17 wt %) currently used in the nuclear fuel reprocessing industry. Characterization and theoretical calculations indicate that among the multiple types of adsorption sites in TGDM, only ionic sites can bond to I2 through strong Coulomb interactions under harsh conditions. The abundant ionic groups of TGDM account for its superior I2 capture performance compared to various benchmark adsorbents. In addition, TGDM exhibits exceptionally high chemical and thermal stabilities that fully meet the requirements of practical radioactive I2 capture (high-temperature, humid, and acidic environment) and differentiate it from other ionic COFs. Furthermore, TGDM has excellent recyclability and low cost, which are unavailable for the current industrial silver-based adsorbents. These advantages make TGDM a promising candidate for capturing I2 vapor during nuclear fuel reprocessing. This strategy of incorporating chemically stable ionic guanidine moieties in COF would stimulate the development of new adsorbents for I2 capture and related applications.