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The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) has significant challenges to human health and clinical treatment, with KPC-2-producing CRKP being the predominant epidemic strain. Therefore, there is an urgent need to identify new therapeutic targets and strategies. Non-coding small RNA (sRNA) is a post-transcriptional regulator of genes involved in important biological processes in bacteria and represents an emerging therapeutic strategy for antibiotic-resistant bacteria. In this study, we analyzed the transcription profile of KPC-2-producing CRKP using RNA-seq. Of the 4693 known genes detected, the expression of 307 genes was significantly different from that of carbapenem-sensitive Klebsiella pneumoniae (CSKP), including 133 up-regulated and 174 down-regulated genes. Both the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment and Gene Ontology (GO) analysis showed that these differentially expressed genes (DEGs) were mainly related to metabolism. In addition, we identified the sRNA expression profile of KPC-2-producing CRKP for the first time and detected 115 sRNAs, including 112 newly discovered sRNAs. Compared to CSKP, 43 sRNAs were differentially expressed in KPC-2-producing CRKP, including 39 up-regulated and 4 down-regulated sRNAs. We chose sRNA51, the most significantly differentially expressed sRNA in KPC-2-producing CRKP, as our research subject. By constructing sRNA51-overexpressing KPC-2-producing CRKP strains, we found that sRNA51 overexpression down-regulated the expression of acrA and alleviated resistance to meropenem and ertapenem in KPC-2-producing CRKP, while overexpression of acrA in sRNA51-overexpressing strains restored the reduction of resistance. Therefore, we speculated that sRNA51 could affect the resistance of KPC-2-producing CRKP by inhibiting acrA expression and affecting the formation of efflux pumps. This provides a new approach for developing antibiotic adjuvants to restore the sensitivity of CRKP.
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Enterobacteriaceae Resistentes a los Carbapenémicos , Klebsiella pneumoniae , ARN Bacteriano , ARN Pequeño no Traducido , beta-Lactamasas , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , beta-Lactamasas/genética , beta-Lactamasas/metabolismo , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Carbapenémicos/farmacología , Regulación Bacteriana de la Expresión Génica , Infecciones por Klebsiella/microbiología , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/genética , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/metabolismo , Klebsiella pneumoniae/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , ARN Bacteriano/genética , ARN Pequeño no Traducido/genéticaRESUMEN
Porcine reproductive and respiratory syndrome (PRRS) is a serious global pig industry disease. Understanding the mechanism of viral replication and developing efficient antiviral strategies are necessary for combating with PRRS virus (PRRSV) infection. Recently, nanobody is considered to be a promising antiviral drug, especially for respiratory viruses. The present study evaluated two nanobodies against PRRSV nucleocapsid (N) protein (PRRSV-N-Nb1 and -Nb2) for their anti-PRRSV activity in vitro and in vivo. The results showed that intracellularly expressed PRRSV-N-Nb1 significantly inhibited PRRSV-2 replication in MARC-145 cells (approximately 100%). Then, the PRRSV-N-Nb1 fused with porcine IgG Fc (Nb1-pFc) as a delivering tag was produced and used to determine its effect on PRRSV-2 replication in porcine alveolar macrophages (PAMs) and pigs. The inhibition rate of Nb1-pFc against PRRSV-2 in PAMs could reach >90%, and it can also inhibit viral replication in vivo. Epitope mapping showed that the motif Serine 105 (S105) in PRRSV-2 N protein was the key amino acid binding to PRRSV-N-Nb1, which is also pivotal for the self-interaction of N protein via binding to Arginine 97. Moreover, viral particles were not successfully rescued when the S105 motif was mutated to Alanine (S105A). Attachment, entry, genome replication, release, docking model analysis, and blocking enzyme-linked immunosorbent assay (ELISA) indicated that the binding of PRRSV-N-Nb1 to N protein could block its self-binding, which prevents the viral replication of PRRSV. PRRSV-N-Nb1 may be a promising drug to counter PRRSV-2 infection. We also provided some new insights into the molecular basis of PRRSV N protein self-binding and assembly of viral particles.IMPORTANCEPorcine reproductive and respiratory syndrome virus (PRRSV) causes serious economic losses to the swine industry worldwide, and there are no highly effective strategies for prevention. Nanobodies are considered a promising novel approach for treating diseases because of their ease of production and low costing. Here, we showed that PRRSV-N-Nb1 against PRRSV-N protein significantly inhibited PRRSV-2 replication in vitro and in vivo. Furthermore, we demonstrated that the motif Serine 105 (S105) in PRRSV-N protein was the key amino acid to interact with PRRSV-N-Nb1 and bond to its motif R97, which is important for the self-binding of N protein. The PRRSV-N-Nb1 could block the self-interaction of N protein following viral assembly. These findings not only provide insights into the molecular basis of PRRSV N protein self-binding as a key factor for viral replication for the first time but also highlight a novel target for the development of anti-PRRSV replication drugs.
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Proteínas de la Nucleocápside , Síndrome Respiratorio y de la Reproducción Porcina , Virus del Síndrome Respiratorio y Reproductivo Porcino , Anticuerpos de Dominio Único , Animales , Aminoácidos , Línea Celular , Proteínas de la Nucleocápside/metabolismo , Síndrome Respiratorio y de la Reproducción Porcina/tratamiento farmacológico , Virus del Síndrome Respiratorio y Reproductivo Porcino/metabolismo , Serina , Anticuerpos de Dominio Único/farmacología , Porcinos , Proteínas no Estructurales Virales/metabolismo , Replicación Viral/efectos de los fármacosRESUMEN
Candida auris is an emerging multidrug-resistant fungal pathogen and a new global threat to human health. A unique morphological feature of this fungus is its multicellular aggregating phenotype, which has been thought to be associated with defects in cell division. In this study, we report a new aggregating form of two clinical C. auris isolates with increased biofilm forming capacity due to enhanced adherence of adjacent cells and surfaces. Unlike the previously reported aggregating morphology, this new aggregating multicellular form of C. auris can become unicellular after treatment with proteinase K or trypsin. Genomic analysis demonstrated that amplification of the subtelomeric adhesin gene ALS4 is the reason behind the strain's enhanced adherence and biofilm forming capacities. Many clinical isolates of C. auris have variable copy numbers of ALS4, suggesting that this subtelomeric region exhibits instability. Global transcriptional profiling and quantitative real-time PCR assays indicated that genomic amplification of ALS4 results in a dramatic increase in overall levels of transcription. Compared to the previously characterized nonaggregative/yeast-form and aggregative-form strains of C. auris, this new Als4-mediated aggregative-form strain of C. auris displays several unique characteristics in terms of its biofilm formation, surface colonization, and virulence.
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Antifúngicos , Candida , Humanos , Candida/genética , Candida auris , Biopelículas , Genómica , Pruebas de Sensibilidad MicrobianaRESUMEN
AIMS: Carbapenem-resistant Klebsiella pneumonia (CRKP) is a global threat that varies by region. The global distribution, evolution, and clinical implications of the ST11 CRKP clone remain obscure. METHODS: We conducted a multicenter molecular epidemiological survey using isolates obtained from 28 provinces and municipalities across China between 2011 and 2021. We integrated sequences from public databases and performed genetic epidemiology analysis of ST11 CRKP. RESULTS: Among ST11 CRKP, KL64 serotypes exhibited considerable expansion, increasing from 1.54% to 46.08% between 2011 and 2021. Combining our data with public databases, the phylogenetic and phylogeography analyses indicated that ST11 CRKP appeared in the Americas in 1996 and spread worldwide, with key clones progressing from China's southeastern coast to the inland by 2010. Global phylogenetic analysis showed that ST11 KL64 CRKP has evolved to a virulent, resistant clade with notable regional spread. Single-nucleotide polymorphism (SNP) analysis identified BMPPS (bmr3, mltC, pyrB, ppsC, and sdaC) as a key marker for this clade. The BMPPS SNP clade is associated with high mortality and has strong anti-phagocytic and competitive traits in vitro. CONCLUSIONS: The high-risk ST11 KL64 CRKP subclone showed strong expansion potential and survival advantages, probably owing to genetic factors.
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Antibacterianos , Infecciones por Klebsiella , Klebsiella pneumoniae , Filogenia , Humanos , China/epidemiología , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/aislamiento & purificación , Infecciones por Klebsiella/epidemiología , Infecciones por Klebsiella/microbiología , Infecciones por Klebsiella/transmisión , Infecciones por Klebsiella/tratamiento farmacológico , Antibacterianos/farmacología , Polimorfismo de Nucleótido Simple , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/efectos de los fármacos , Enterobacteriaceae Resistentes a los Carbapenémicos/aislamiento & purificación , Epidemiología Molecular , Carbapenémicos/farmacología , Pruebas de Sensibilidad Microbiana , Filogeografía , Serogrupo , Genómica/métodosRESUMEN
Regulating the built-in electric field (BEF) in the heterojunction is is a great challenge in developing high-efficiency photocatalysts. Herein, by tailoring the content of oxygen vacancies in the constituent reduction semiconductor (mesoporous CeO2-x ), a precise Fermi level (EF ) regulation of CeO2-x is realized, yielding an amplified EF gap and intensified BEF in the Cs3 Bi2 Br9 perovskite quantum dots/CeO2-x S-scheme heterojunction. Such an enhanced BEF offers a strong driving force for directional electron transfer, boosting charge separation in the S-scheme heterojunction. As a result, the optimized Cs3 Bi2 Br9 /CeO2-x heterojunction delivers a remarkable CO2 conversion efficiency, with an impressive CO production rate of 80.26 µmol g-1 h-1 and a high selectivity of 97.6%. The S-scheme charge transfer mode is corroborated comprehensively by density functional theory (DFT) calculations, in situ X-ray photoelectron spectroscopy (XPS), and photo-irradiated Kelvin probe force microscopy (KPFM). Moreover, diffuse reflectance infrared Fourier transform spectra (DRIFTS) and theoretical calculations are conducted cooperatively to reveal the CO2 photoreduction pathway.
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Photothermal catalysis, which applies solar energy to produce photogenerated e-/h+ pairs as well as provide heat input, is recognized as a promising technology for high conversion efficiency of CO2 to value-added solar fuels. In this work, a "shooting three birds with one stone" approach is demonstrated to significantly enhance the photothermal CO2 reduction over the Cs3Bi2Br9@Co3O4 (CBB@Co3O4) heterostructure. Initially, Co3O4 with photoinduced self-heating effect serves as a photothermal material to elevate the temperature of the photocatalyst, which kinetically accelerates the catalytic reaction. Meanwhile, a p-n heterojunction is constructed between the p-type Co3O4 and n-type Cs3Bi2Br9 semiconductors, which has an intrinsic built-in electric field (BEF) to facilitate the separation of photogenerated e-/h+ pairs. Furthermore, the mesoporous Co3O4 matrix can afford abundant active sites for promoting adsorption/activation of CO2 molecules. Benefiting from these synergistic effects, the as-developed CBB@Co3O4 heterostructure achieves an impressive CO2-to-CO conversion rate of 168.56 µmol g-1 h-1 with no extra heat input. This work provides an insightful guidance for the construction of effective photothermal catalysts for CO2 reduction with high solar-to-fuel conversion efficiency.
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Water electrolysis has become an attractive hydrogen production method. Oxygen evolution reaction (OER) is a bottleneck of water splitting as its four-electron transfer procedure presents sluggish reaction kinetics. Designing composite catalysts with high performance for efficient OER still remains a huge challenge. Here, the P-doped cobalt oxide/NiFe layered double hydroxides (P-CoOX/NiFe LDHs) composite catalysts with amorphous/crystalline interfaces are successfully prepared for OER by hydrothermal-electrodeposition combined method. The results of electrochemical characterizations, operando Raman spectra, and DFT theoretical calculations have demonstrated the electrons in the P-CoOX/NiFe LDHs heterointerfaces are easily transferred from Ni2+ to Co3+ because that the amorphous configuration of P-CoOX can well induce Ni-O-Co orbital coupling. The electron transfer of Ni2+ to the surrounding Fe3+ and Co3+ will lead to the unoccupied eg orbitals of Ni3+ that can promote water dissociation and accelerate *OOH migration to improve OER catalytic performance. The optimized P-CoOX/NiFe LDHs exhibit superior catalytic performance for OER with a very low overpotential of 265 mV at 300 mA cm-2 and excellent long-term stability of 500 h with almost no attenuation at 100 mA cm-2. This work will provide a new method to design high-performance NiFe LDHs-based catalysts for OER.
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Flexible rechargeable Zn-air batteries (FZABs) exhibit high energy density, ultra-thin, lightweight, green, and safe features, and are considered as one of the ideal power sources for flexible wearable electronics. However, the slow and high overpotential oxygen reaction at the air cathode has become one of the key factors restricting the development of FZABs. The improvement of activity and stability of bifunctional catalysts has become a top priority. At the same time, FZABs should maintain the battery performance under different bending and twisting conditions, and the design of the overall structure of FZABs is also important. Based on the understanding of the three typical configurations and working principles of FZABs, this work highlights two common strategies for applying bifunctional catalysts to FZABs: 1) powder-based flexible air cathode and 2) flexible self-supported air cathode. It summarizes the recent advances in bifunctional oxygen electrocatalysts and explores the various types of catalyst structures as well as the related mechanistic understanding. Based on the latest catalyst research advances, this paper introduces and discusses various structure modulation strategies and expects to guide the synthesis and preparation of efficient bifunctional catalysts. Finally, the current status and challenges of bifunctional catalyst research in FZABs are summarized.
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A long-term goal of rechargeable zinc-air batteries (ZABs) has always been to design bifunctional electrocatalysts that are robust, effective, and affordable for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). It has become a feasible method to construct metal/metal oxide interfaces to achieve superior electrocatalytic performance for ORR and OER by enhanced charge transfer. In this study, Co/Co3O4 heterojunctions were successfully prepared and encased in porous N-doped mesoporous carbon (Co/Co3O4@NC) via a simple condensation-carbonization-etching method. The extensive specific surface area of Co/Co3O4@NC facilitates effective interaction between the electrolyte and the catalyst, thereby enabling sufficient exposure of active sites for the ORR and the OER, consequently enhancing the rate of transport of active species. The well-designed Co/Co3O4@NC delivers superior ORR catalytic activity with a half-wave potential of 0.82 V (vs RHE) and a low overpotential of 347 mV at 10 mA cm-2 for OER in alkaline solution. The power density of Co/Co3O4@NC-based alkaline aqueous ZAB (156.5 mW cm-2) is superior to the commercial Pt/C + IrO2-based alkaline aqueous ZAB, and the cycling stability of ZAB is up to 220 h. In addition, Co/Co3O4@NC-based ZAB shows a high power density (50.1 mW cm-2). The construction of metal/metal oxide heterojunction encased in N-doped mesoporous carbon provides a novel route for the design of bifunctional electrocatalysts for high-performance ZABs.
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An organo-photoredox catalyzed gem-difluoroallylation of both acyclic and cyclic ketone derivatives with α-trifluoromethyl alkenes has been demonstrated, thus giving access to a diverse set of gem-difluoroalkenes in moderate to high yields. Pro-aromatic dihydroquinazolinones can be either pre-formed or in situ generated for ketone activation. This reaction is characterized by readily available starting materials, mild reaction conditions, and broad substrate scope. The feasibility of this reaction has been highlighted by the late-stage modification of several natural products and drug-like molecules as well as the in vitro antifungal activity.
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Contamination by neonicotinoid (NEO) insecticides in surface waters is a global problem. Nevertheless, the occurrence of NEOs in lakes is not well known. Hongze Lake, the largest impounded lake on the Eastern Route of the South-to-North Water Diversion Project, was selected to investigate the distribution, ecological risks, and health risks of NEOs. Water samples from the lake and nearby rivers were collected and analyzed for 8 widely used NEOs in three seasons. The results indicated the average total NEO concentration in summer, winter, and spring was 222, 211, and 244 ng L-1 for the river water, and 265, 213, and 181 ng L-1 for the lake water, respectively, with no statistical seasonal difference. For the river water, the highest total NEO concentration in the three seasons was observed in the Andong River. For the lake water, the total NEO concentrations in summer were relatively high in sites near the inflow river estuaries due to the high riverine inputs during the flood period. The spatial difference in NEO concentration was relatively low in winter, which may be related to the wind-driven lake current. The seasonal variation in NEO compositions in the lake was generally similar to that in the river, indicating riverine input was the important source for the lake. Huai River was the largest contributor to the NEO inputs to the lake, and Sanhe Gate was the major output pathway. Clothianidin and imidacloprid in the river and lake water would produce moderate acute ecological risks in summer. Thus, the usage of the above two NEOs should be decreased or restricted. For integral NEO risks, 53% and 58% of the river and lake water sites exceeded the acute ecological threshold, respectively. Health risk assessment suggested drinking the water obtained from the lake would not produce a negative impact on public health.
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OBJECTIVE: To review the effectiveness of different physical therapies for acute and sub-acute low back pain supported by evidence, and create clinical recommendations and expert consensus for physiotherapists on clinical prescriptions. DATA SOURCES: A systematic search was conducted in PubMed and the Cochrane Library for studies published within the previous 15 years. REVIEW METHODS: Systematic review and meta-analysis, randomized controlled trials assessing patients with acute and sub-acute low back pain were included. Two reviewers independently screened relevant studies using the same inclusion criteria. The Physiotherapy Evidence Database and the Assessment of Multiple Systematic Reviews tool were used to grade the quality assessment of randomized controlled trials and systematic reviews, respectively. The final recommendation grades were based on the consensus discussion results of the Delphi of 22 international experts. RESULTS: Twenty-one systematic reviews and 21 randomized controlled trials were included. Spinal manipulative therapy and low-level laser therapy are recommended for acute low back pain. Core stability exercise/motor control, spinal manipulative therapy, and massage can be used to treat sub-acute low back pain. CONCLUSIONS: The consensus statements provided medical staff with appliable recommendations of physical therapy for acute and sub-acute low back pain. This consensus statement will require regular updates after 5-10 years.
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Dolor de la Región Lumbar , Modalidades de Fisioterapia , Humanos , Dolor de la Región Lumbar/rehabilitación , Dolor de la Región Lumbar/terapia , Consenso , Ensayos Clínicos Controlados Aleatorios como Asunto , Femenino , Dolor Agudo/terapia , Dolor Agudo/rehabilitación , MasculinoRESUMEN
Death attitudes can have significant impacts on individuals' mental health. The present study used a person-centered approach to identify 588 Chinese college students' profiles of death attitudes (i.e., fear of death, death avoidance, neutral acceptance, escape acceptance, and approach acceptance), as well as their associations with socio-demographic factors and mental health outcomes. Latent profile analysis identified five subgroups of students: healthy (28.8%), acceptant (11.7%), indifferent (43.5%), paradoxical (10.7%), and avoidant (5.3%). The healthy profile had the most favorable mental health outcomes, whereas the paradoxical profile had the least favorable mental health outcomes. Moreover, women and students from better-resourced universities were more likely to report adaptive patterns of death attitudes. Our findings demonstrated the advantages of using a person-centered approach to achieve a more nuanced understanding of Chinese college students' death attitudes in relation to their mental health. The findings can inform death-related education and mental health interventions for college students.
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Miedo , Salud Mental , Humanos , Femenino , Estudiantes/psicología , UniversidadesRESUMEN
BACKGROUND: Strawberry, being an important economic crop, requires a large amount of human labor for harvesting operations. Efficient and non-destructive harvesting by strawberry harvesting robots requires the precise location of the picking points. Current algorithms for locating picking points encounter significant issues with location errors and minimal effective information in complex situations. RESULTS: To improve the accuracy of the location of picking points, this study proposes a visual location method based on composite models. This method employs object detection and instance segmentation models to detect fruits and segment peduncles sequentially, thereby enabling the identification of picking points and inclination on the peduncle. Different object detection algorithms and instance segmentation models were validated to explore the optimal model combination, and the Convolutional Block Attention Module (CBAM) was integrated into YOLOv8s-seg to construct YOLOv8s-seg-CBAM. Test results show that the composite model built with YOLOv8s and YOLOv8s-seg-CBAM achieved a peduncle detection accuracy of 86.2%, with an inference time of 30.6 ms per image. CONCLUSION: The picking point visual location method based on YOLOv8s and YOLOv8s-seg-CBAM composite models can better balance accuracy and efficiency and can provide more accurate guidance for automated harvesting. © 2024 Society of Chemical Industry.
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Compared with the traditional electrolysis of water to produce hydrogen, urea-assisted electrolysis of water to produce hydrogen has significant advantages and has received extensive attention from researchers. Unfortunately, urea oxidation reaction (UOR) involves a complex six-electron transfer process leading to high overpotential, which forces researchers to develop high-performance UOR catalysts to drive the development of urea-assisted water splitting. Based on the UOR mechanism and extensive literature research, this review summarizes the strategies for preparing highly efficient UOR catalysts. First, the UOR mechanism is introduced and the characteristics of excellent UOR catalysts are pointed out. Aiming at this, the following modulation strategies are proposed to improve the catalytic performance based on summarizing various literature: 1) Accelerating the active phase formation to reduce initial potential; 2) Creating double active sites to trigger a new UOR mechanism; 3) Accelerating urea adsorption and promoting CâN bond cleavage to ensure the effective conduct of UOR; 4) Promoting the desorption of CO2 to improve stability and prevent catalyst poisoning; 5) Promoting electron transfer to overcome the inherent slow dynamics of UOR; 6) Increasing active sites or active surface area. Then, the application of UOR in electrochemical devices is summarized. Finally, the current deficiencies and future directions are discussed.
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In March 2022, the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) surged during the Coronavirus Disease 2019 (COVID-19) pandemic in Shanghai, but over 90% of patients were mild. This study included 1139 COVID-19 patients mildly infected with the Omicron variant of SARS-CoV-2 in Shanghai from May 1 to 10, 2022, aiming to clarify the demographic characteristics and clinical symptoms of patients with mild Omicron infection. The clinical phenotypes of Omicron infection were identified by model-based cluster analysis to explore the features of different clusters. The median age of the patients was 41.0 years [IQR: 31.0-52.0 years] and 73.0% were male. The top three clinical manifestations are cough (57.5%), expectoration (48.3%), and nasal congestion and runny nose (43.4%). The prevalence of nasal congestion and runny nose varied significantly across the doses of vaccinations, with 23.1% in the unvaccinated population and 30%, 45.9%, and 44.3% in the 1-dose, 2-dose and 3-dose vaccinated populations, respectively. In addition, there were significant differences for fever (23.1%, 26.0%, 28.6%, 18.4%), head and body heaviness (15.4%, 14.0%, 26.7%, 22.4%), and loss of appetite (25.6%, 30.0%, 33.6%, 27.7%). The unvaccinated population had a lower incidence of symptoms than the vaccinated population. Cluster analysis revealed that all four clusters had multisystemic symptoms and were dominated by both general and respiratory symptoms. The more severe the degree of the symptoms was, the higher the prevalence of multisystemic symptoms will be. The Omicron variant produced a lower incidence of symptoms in mildly infected patients than previous SARS-CoV-2 variants, but the clinical symptoms caused by the Omicron variant are more complex, so that it needs to be differentiated from influenza.
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COVID-19 , Masculino , Femenino , Humanos , COVID-19/epidemiología , SARS-CoV-2 , China/epidemiología , RinorreaRESUMEN
The Omicron variant has become the dominant COVID-19 variant worldwide due to its rapid and cryptic spread. Therefore, successful early warning is of great importance to be able to control epidemics in their early phase, before developing into large outbreaks. COVID-19-related Baidu search index, which reflects human behavior to a certain degree, was used to retrospectively detect the warning signs for Omicron variant outbreaks in China in 2022. The characteristics and effects of warning signs were analyzed in detail. We detected the presence of early warning signs (both high and low thresholds) and found that these occurred 4-7 days earlier than traditional epidemiological surveillance and >20 days earlier than the implementation of the local "lockdown" policy. Compared with the "high threshold" warning, the early warning effect of the "low threshold" is also vital because it indicates a negligence about epidemic prevention and control. However, there is obvious heterogeneity in the optimal threshold for detecting early warning signs and their distribution in different cities. Multi-source and multi-point early warning systems should be established via combining internet-based big data in the future to conduct effective and early real-time warning. This would create precious time for the early control of COVID-19 outbreaks.
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COVID-19 , SARS-CoV-2 , Humanos , Estudios Retrospectivos , COVID-19/diagnóstico , COVID-19/epidemiología , Brotes de Enfermedades , China/epidemiologíaRESUMEN
Cancer stem cells (CSCs), also known as tumor initiating cells or tumor repopulating cells, which comprise only a small fraction of tumor, have received tremendous attention during the past two decades, as they are considered as the ringleader for initiation and progression of tumors, therapy resistance, metastasis, and recurrence in the clinic. Hence, eradicating CSCs is critical for successful cancer treatment. To that end, various CSC-targeting therapeutic agents have been pursued. However, these CSC-specific drugs are ineffective toward bulk cancer cells. Furthermore, these anti-CSC drugs not only eradicate CSCs but also affect conventional stem cells in normal organs or tissues. By virtue of the enhanced permeability and retention (EPR) effect, nanomaterial drug delivery systems (NDDSs) passively accumulate in tumor tissues, thereby alleviating severe side effects toward normal viscera. NDDSs can be further functionalized with CSC-specific binding molecules to promote targeted drug delivery toward CSCs. Moreover, NDDSs have unique advantages in encapsulating CSC-specific drugs and cytotoxic agents, realizing synchronized killing of CSCs and bulk cancer cells both temporally and spatially. For these reasons, leveraging nanotherapeutic strategies to target CSCs has gained tremendous attention recently.Some ten years ago, we summarized five basic features of efficient nanotherapeutics (the five features principle), which consist of long circulation, tumor accumulation, deep penetration, cellular internalization, and drug release. Based on this design rationale, we constructed several NDDSs, including nanogels with adaptive hydrophobicity, CSC-derived microparticles with tailored softness, and tumor exosome sheathed porous silicon biomimetic nanoparticles, for targeted drug delivery to tumor. To our astonishment, these NDDSs that possess the five basic features achieve decent drug delivery efficiency toward not only bulk tumor cells but more importantly CSCs. Consequently, such nanotherapeutics as-designed based on the five features principle are potent in eradicating CSCs, even with only cytotoxic drugs, for instance, doxorubicin. Furthermore, commercialized nanomedicines, such as Doxil and Abraxane, can be endowed with these five basic features by hyperbaric oxygen therapy and therefore achieve outstanding drug delivery efficiency, potent CSC elimination, and efficient cancer therapy. These studies suggest that intractable CSCs can be tackled with a material-based approach, highlight the critical role of the five features principle in designing effective nanotherapeutics, and pinpoint the significance of drug delivery efficiency in eliminating CSCs and bulk cancer cells.
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Antineoplásicos , Nanopartículas , Neoplasias , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Sistemas de Liberación de Medicamentos , Humanos , Nanopartículas/química , Neoplasias/patología , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patologíaRESUMEN
PURPOSE: The combined application of immune checkpoint inhibitors (ICIs) and anti-angiogenesis therapy has shown synergistic effects on glioblastoma (GBM). As important resources of PD-L1 in the tumor microenvironment (TME), tumor-associated macrophages (TAMs) have significant impact of the efficiency of ICIs. However, the effects of anti-angiogenesis agents on immune checkpoints expression are not fully understood. METHOD: GBM-educated macrophages were generated from circulating monocytes of healthy controls and GBM patients under the education of GBM cell line. Surface expression of PD-L1 and VEGFR1 on GBM-educated macrophages was analyzed. VEGFR1 NAb and soluble VEGFR1 (sVEGFR1) were added and their effects on PD-L1 expression on TAMs was investigated. Serum soluble PD-L1 (sPD-L1) and sVEGFR1 levels in GBM patients were measured and their correlation was analyzed. RESULT: The expression intensity of PD-L1 on GBM-educated macrophages was higher and its up-regulation partially depends on VEGFR1 signaling pathway. GBM-educated macrophages secreted less levels of soluble VEGFR1 (sVEGFR1), and exogenous sVEGFR1 down-regulated PD-L1 expression intensity. PD-L1 blockade promoted the secretion of sVEGFR1. Finally, sVEGFR1 and sPD-L1 in serum of GBM patients were overexpressed, and a positive correlation was found. CONCLUSION: These findings reveal the interaction between PD-L1 and VEGFR1 signaling pathway in GBM-educated macrophages. VEGFR1 is involved with PD-L1 overexpression, which can be impeded by autocrine regulation of sVEGFR1. sVEGFR1 secretion by GBM-educated macrophages can be promoted by PD-L1 blockade. Taken together, these findings provide evidences for the combined application of ICIs and anti-angiogenesis therapies in the treatment of GBM.
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Antígeno B7-H1 , Glioblastoma , Receptor 1 de Factores de Crecimiento Endotelial Vascular , Humanos , Antígeno B7-H1/metabolismo , Línea Celular , Glioblastoma/patología , Macrófagos/metabolismo , Monocitos/patología , Microambiente Tumoral , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Three-component alkene 1,2-difunctionalizations have emerged as a powerful strategy for rapid buildup of diverse and complex alkylpyridines, but the distal functionalized alkyl radicals for the alkene 1,2-alkylpyridylations were still rare. Herein, we report an example of regioselective three-component 1,2-cyanoalkylpyridylation of feedstock styrenes with accessible nonredox-active cyclic oximes through visible-light photoredox catalysis, providing a series of structurally diverse ß-cyanoalkylated alkylpyridines. This protocol proceeds through a radical relay pathway including the generation of iminyl radicals enabled by phosphoranyl radical-mediated ß-scission, radical transposition through C-C bond cleavage, highly selective radical addition, and precise radical-radical cross-coupling sequence, thus facilitating the regioselective formation of two distinct C-C single bonds in a single-pot operation. This synthetic strategy features mild conditions, broad compatibility of functional groups and substrate scope, diverse product derivatization, and late-stage modification.