Radical cascade cyclizations of o‐allyloxybenzaldehydes have emerged as a powerful strategy for the synthesis of 3‐substituted chroman‐4‐ones. This minireview summarizes the incorporation of various ...functional groups into the C3‐position of chroman‐4‐ones by employing appropriate radical precursors through transition‐metal‐free systems, silver‐catalyzed systems, or visible‐light‐promoted systems.
This minireview summarizes radical reactions for incorporating various functional groups into the C3‐position of chroman‐4‐ones. The generation of radicals can be accomplished using transition metal free systems, silver‐based systems, or photoredox catalysts under visible‐light irradiation.
Resistance to chemotherapy is a major challenge for the treatment of patients with colorectal cancer (CRC). Previous studies have found that microRNAs (miRNAs) play key roles in drug resistance; ...however, the role of miRNA‐373‐3p (miR‐375‐3p) in CRC remains unclear. The current study aimed to explore the potential function of miR‐375‐3p in 5‐fluorouracil (5‐FU) resistance. MicroRNA‐375‐3p was found to be widely downregulated in human CRC cell lines and tissues and to promote the sensitivity of CRC cells to 5‐FU by inducing colon cancer cell apoptosis and cycle arrest and by inhibiting cell growth, migration, and invasion in vitro. Thymidylate synthase (TYMS) was found to be a direct target of miR‐375‐3p, and TYMS knockdown exerted similar effects as miR‐375‐3p overexpression on the CRC cellular response to 5‐FU. Lipid‐coated calcium carbonate nanoparticles (NPs) were designed to cotransport 5‐FU and miR‐375‐3p into cells efficiently and rapidly and to release the drugs in a weakly acidic tumor microenvironment. The therapeutic effect of combined miR‐375 + 5‐FU/NPs was significantly higher than that of the individual treatments in mouse s.c. xenografts derived from HCT116 cells. Our results suggest that restoring miR‐375‐3p levels could be a future novel therapeutic strategy to enhance chemosensitivity to 5‐FU.
Resistance to chemotherapy is a major challenge for the treatment of patients with colorectal cancer (CRC). Our results suggest that the restoration of microRNA‐375‐3p levels could be a future novel therapeutic strategy to modulate and enhance chemosensitivity to 5‐fluorouracil treatment in CRC.
Background and Aims
Nonalcoholic steatohepatitis (NASH) is a common cause of chronic liver disease. Clinical trials use the NASH Clinical Research Network (CRN) system for semiquantitative ...histological assessment of disease severity. Interobserver variability may hamper histological assessment, and diagnostic consensus is not always achieved. We evaluate a second harmonic generation/two‐photon excitation fluorescence (SHG/TPEF) imaging‐based tool to provide an automated quantitative assessment of histological features pertinent to NASH.
Approach and Results
Images were acquired by SHG/TPEF from 219 nonalcoholic fatty liver disease (NAFLD)/NASH liver biopsy samples from seven centers in Asia and Europe. These were used to develop and validate qFIBS, a computational algorithm that quantifies key histological features of NASH. qFIBS was developed based on in silico analysis of selected signature parameters for four cardinal histopathological features, that is, fibrosis (qFibrosis), inflammation (qInflammation), hepatocyte ballooning (qBallooning), and steatosis (qSteatosis), treating each as a continuous rather than categorical variable. Automated qFIBS analysis outputs showed strong correlation with each respective component of the NASH CRN scoring (P < 0.001; qFibrosis r = 0.776, qInflammation r = 0.557, qBallooning r = 0.533, and qSteatosis r = 0.802) and high area under the receiver operating characteristic curve values (qFibrosis 0.870‐0.951; 95% confidence interval {CI}, 0.787‐1.000; P < 0.001, qInflammation 0.820‐0.838; 95% CI, 0.726‐0.933; P < 0.001), qBallooning 0.813‐0.844; 95% CI, 0.708‐0.957; P < 0.001, and qSteatosis 0.939‐0.986; 95% CI, 0.867‐1.000; P < 0.001) and was able to distinguish differing grades/stages of histological disease. Performance of qFIBS was best when assessing degree of steatosis and fibrosis, but performed less well when distinguishing severe inflammation and higher ballooning grades.
Conclusions
qFIBS is an automated tool that accurately quantifies the critical components of NASH histological assessment. It offers a tool that could potentially aid reproducibility and standardization of liver biopsy assessments required for NASH therapeutic clinical trials.
Fusarium graminearum is a destructive wheat pathogen. No fully resistant cultivars are available. Knowledge concerning the molecular weapons of F. graminearum to achieve infection remains limited. ...Here, we report that deletion of the putative secondary metabolite biosynthesis gene cluster fg3_54 compromises the pathogen's ability to infect wheat through cell-to-cell penetration. Ectopic expression of fgm4, a pathway-specific bANK-like regulatory gene, activates the transcription of the fg3_54 cluster in vitro. We identify a linear, C- terminally reduced and D-amino acid residue-rich octapeptide, fusaoctaxin A, as the product of the two nonribosomal peptide synthetases encoded by fg3_54. Chemically-synthesized fusaoctaxin A restores cell-to-cell invasiveness in fg3_54-deleted F. graminearum, and enables colonization of wheat coleoptiles by two Fusarium strains that lack the fg3_54 homolog and are nonpathogenic to wheat. In conclusion, our results identify fusaoctaxin A as a virulence factor required for cell-to-cell invasion of wheat by F. graminearum.
Separation of p‐xylene (kinetic diameter ca. 0.58 nm) from its bulkier isomers (o‐xylene and m‐xylene, ca. 0.68 nm) is challenging, but important in the petrochemical industry. Herein, we developed a ...highly selective and stable metal–organic framework (MOF) MIL‐160 membrane for selective separation of p‐xylene from its isomers by pervaporation. The suitable pore size (0.5∼0.6 nm) of the MIL‐160 membrane selectively allows p‐xylene to pass through, while excluding the bulkier o‐xylene and m‐xylene. For the separation of equimolar binary p‐/o‐xylene mixtures at 75 °C, high p‐xylene flux of 467 g m−2 h−1 and p‐/o‐xylene selectivity of 38.5 could be achieved. The stability of MIL‐160, ensured the separation performance of the MIL‐160 membrane was unchanged over a 24 h measurement. The high separation performance combined with its high thermal and chemical stability makes the MIL‐160 membrane a promising candidate for the separation of xylene isomers.
Come on xylene: Through chemical modification of the Al2O3 support by bio‐inspired polydopamine, a highly selective and stable MIL‐160 membrane was developed for separation of p‐xylene from its isomers by pervaporation. Attributed to its suitable pore size (0.5≈0.6 nm), the MIL‐160 membrane selectively allows p‐xylene to pass through, while excluding the bulkier o‐xylene and m‐xylene.
Abstract
A disturbance of reactive oxygen species (ROS) homeostasis may cause the pathogenesis of many diseases. Inspired by natural photosynthesis, this work proposes a photo-driven H
2
-evolving ...liposomal nanoplatform (Lip NP) that comprises an upconversion nanoparticle (UCNP) that is conjugated with gold nanoparticles (AuNPs) via a ROS-responsive linker, which is encapsulated inside the liposomal system in which the lipid bilayer embeds chlorophyll
a
(Chl
a
). The UCNP functions as a transducer, converting NIR light into upconversion luminescence for simultaneous imaging and therapy in situ. Functioning as light-harvesting antennas, AuNPs are used to detect the local concentration of ROS for FRET biosensing, while the Chl
a
activates the photosynthesis of H
2
gas to scavenge local excess ROS. The results thus obtained indicate the potential of using the Lip NPs in the analysis of biological tissues, restoring their ROS homeostasis, possibly preventing the initiation and progression of diseases.
Work-family balance has received meaningful attention from researchers and practitioners alike. Work and family are usually seen as two separate domains that are interdependent, with boundaries that ...have some level of permeability. Crisis situations can alter permeability of these boundaries, enhancing integration of the two domains due to exchange of ideas and spillover of concerns between these domains. This study looks at how these boundaries are impacted for nurses working directly with COVID-19 patients. The study conducted 24 semi-structured interviews with nurses. Through a thematic analysis the study found that the work-family boundaries have blurred due to concerns around the contagiousness and anxiety associated with the virus. In order to cope with these spillover and possible crossover effects, nurses use prosocial distortion and avoidance and create sub-boundaries at home.
This review summarized several main factors influencing fermentative hydrogen production. The reviewed factors included inoculum, substrate, reactor type, nitrogen, phosphate, metal ion, temperature ...and pH. In this review, the effect of each factor on fermentative hydrogen production and the advance in the research of the effect were briefly introduced and discussed, followed by some suggestions for the future work of fermentative hydrogen production. This review showed that there usually existed some disagreements on the optimal condition of a given factor for fermentative hydrogen production, thus more researches in this respect are recommended. Furthermore, most of the studies on fermentative hydrogen production were conducted in batch mode using glucose and sucrose as substrate, thus more studies on fermentative hydrogen production in continuous mode using organic wastes as substrate are recommended.
Summary
Autoimmunity in plants has been found in numerous hybrids as a form of hybrid necrosis and mutant panels. Uncontrolled cell death is a main cellular outcome of autoimmunity, which negatively ...impacts growth. Its occurrence highlights the vulnerable nature of the plant immune system. Genetic investigation of autoimmunity in hybrid plants revealed that extreme variation in the immune receptor repertoire is a major contributor, reflecting an evolutionary conundrum that plants face in nature. In this review, we discuss natural variation in the plant immune system and its contribution to fitness. The value of autoimmunity genetics lies in its ability to identify combinations of a natural immune receptor and its partner that are predisposed to triggering autoimmunity. The network of immune components for autoimmunity becomes instrumental in revealing mechanistic details of how immune receptors recognize cellular invasion and activate signaling. The list of autoimmunity‐risk variants also allows us to infer evolutionary processes contributing to their maintenance in the natural population. Our approach to autoimmunity, which integrates mechanistic understanding and evolutionary genetics, has the potential to serve as a prognosis tool to optimize immunity in crops.
The hydrogenation of sequestrated CO2 to methanol can reduce CO2 emission and establish a sustainable carbon circuit. However, the transformation of CO2 into methanol is challenging because of the ...thermodynamic equilibrium limitation and the deactivation of catalysts by water. In the present work, different reactor types have been evaluated for CO2 catalytic hydrogenation to methanol. Best results have been obtained in a bifunctional catalytic membrane reactor (CMR) based on a zeolite LTA membrane and a catalytic Cu‐ZnO‐Al2O3‐ZrO2 layer on top. Due to the in situ and rapid removal of the produced water from the catalytic layer through the hydrophilic zeolite LTA membrane, it is effective to break the thermodynamic equilibrium limitation, thus significantly increasing the CO2 conversion (36.1 %) and methanol selectivity (100 %). Further, the catalyst deactivation by the produced water can be effectively inhibited, thus maintaining a high long‐term activity of the CMR.
A bifunctional catalytic membrane reactor is developed for CO2 conversion to methanol, in which CO2 conversion to methanol and the by‐product water removal by hydrophilic zeolite LTA membrane is realized simultaneously. Attributing to in situ and continuous removal of water from the reaction system, the equilibrium limitation of CO2 conversion to methanol is broken, leading to a significant enhancement of CO2 conversion and methanol selectivity.
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