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Due to inherent differences in cellular composition and metabolic behavior with host cells, tumor-harbored bacteria can discriminatorily affect tumor immune landscape. However, the mechanisms by which intracellular bacteria affect antigen presentation process between tumor cells and antigen-presenting cells (APCs) are largely unknown. The invasion behavior of attenuated Salmonella VNP20009 (VNP) into tumor cells is investigated and an attempt is made to modulate this behavior by modifying positively charged polymers on the surface of VNP. It is found that non-toxic chitosan oligosaccharide (COS) modified VNP (VNP@COS) bolsters the formation of gap junction between tumor cells and APCs by enhancing the ability of VNP to infect tumor cells. On this basis, a bacterial biohybrid is designed to promote in situ antigen cross-presentation through intracellular bacteria induced gap junction. This bacterial biohybrid also enhances the expression of major histocompatibility complex class I molecules on the surface of tumor cells through the incorporation of Mdivi-1 coupled with VNP@COS. This strategic integration serves to heighten the immunogenic exposure of tumor antigens; while, preserving the cytotoxic potency of T cells. A strategy is proposed to precisely controlling the function and local effects of microorganisms within tumors.
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Presentación de Antígeno , Quitosano , Uniones Comunicantes , Salmonella , Humanos , Quitosano/química , Línea Celular Tumoral , Uniones Comunicantes/metabolismo , Salmonella/inmunología , Animales , Reactividad Cruzada , Ratones , Oligosacáridos/química , Neoplasias/inmunología , Neoplasias/patología , Células Presentadoras de Antígenos/inmunología , Antígenos de Histocompatibilidad Clase I/metabolismo , Antígenos de Histocompatibilidad Clase I/inmunologíaRESUMEN
Valproate (valproic acid, VPA), a drug for the treatment of epilepsy and bipolar disorder, causes liver steatosis with enhanced oxidative stress. Accumulating evidences exhibite that gut microbiota plays an important role in progression of nonalcoholic fatty liver disease (NAFLD). However, whether gut microbiota contributes to VPA-caused hepatic steatosis needs to be elucidated. A mixture of five probiotics was selected to investigate their effects on liver steatosis and oxidative stress in mice orally administered VPA for 30 days. Probiotics treatment significantly attenuated the hepatic lipid accumulation in VPA-treated mice via inhibiting the expression of cluster of differentiation 36 (CD36) and distinct diacylglycerol acyltransferase 2 (DGAT2). Meanwhile, probiotics exerted a protective effect against VPA-induced oxidative stress by decreasing the pro-oxidant cytochrome P450 2E1 (CYP2E1) level and activating the Nrf2/antioxidant enzyme pathway. Moreover, VPA treatment altered the relative abundance of gut microbiota at the phylum, family and genera levels, while probiotics partially restored these changes. Spearman's correlation analysis showed that several specific genera and family were significantly correlated with liver steatosis and oxidative stress-related indicators. These results suggest that probiotics exert their health benefits in the abrogation of liver steatosis and oxidative stress in VPA-treated mice by manipulating the microbial homeostasis.
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Enfermedad del Hígado Graso no Alcohólico , Probióticos , Ratones , Animales , Ácido Valproico/farmacología , Ácido Valproico/metabolismo , Hígado/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Estrés Oxidativo , Probióticos/farmacología , Probióticos/uso terapéuticoRESUMEN
Ketoprofen (KTP) as a non-steroidal anti-inflammatory drug has been detected in coastal environment due to its wide usage. However, little information is available about the fate of KTP in marine environment. In the present study, the aerobic degradation of 20 mg L-1 KTP using the enriched marine consortia was investigated. Results showed that CA consortium cultured with casamino acids exhibited a higher KTP-degrading ability than those cultured with glucose, yeast extract and mixed vitamins. During CA consortium-mediated degradation of KTP, additional casamino acids resulted in the production of H2O2 and OH. Fe(III) could be also reduced to Fe(II) by CA consortium. This result indicated the occurrence of Fenton-like reaction. Further studies found that both biogenic Fenton-like reaction and enzyme-catalyzed reactions were involved in the initial hydroxylation reaction of KTP, then the subsequent mineralization of KTP was only performed via enzyme-catalyzed reactions. High-throughput sequencing analysis showed that Halomonas, Marinobacter, Owenweeksia and Oceanimonas were significantly enriched in CA consortium. As these genera contain amino acid oxidases, and the former two genera are capable of reducing Fe(III), it is assumed that these genera participated in biogenic Fenton-like reaction. The involvement of biogenic Fenton-like reaction provides a new insight into understanding the fate of KTP and other similar organic pollutants in marine environment containing amino acids and iron.
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Compuestos Férricos , Cetoprofeno , Peróxido de Hidrógeno/química , Oxidación-Reducción , Hierro/químicaRESUMEN
As an emerging cancer treatment strategy, ferroptosis is greatly restricted by excessive glutathione (GSH) in tumor microenvironment (TME) and low reactive oxygen species (ROS) generation efficiency. Here, this work designs self-assembled copper-alanine nanoparticles (CACG) loaded with glucose oxidase (GOx) and cinnamaldehyde (Cin) for in situ glutathione activated and enzymatic cascade-enhanced ferroptosis and immunotherapy. In response to GSH-rich and acidic TME, CACG allows to effectively co-deliver Cu2+ , Cin, and GOx into tumors. Released Cin consumes GSH through Michael addition, accompanying with the reduction of Cu2+ into Cu+ for further GSH depletion. With the cascade of Cu+ -catalyzed Fenton reactions and enzyme-catalyzed reactions by GOx, CACG could get rid of the restriction of insufficient hydrogen peroxide in TME, leading to a robust and constant generation of ROS. With the high efficiency of GSH depletion and ROS production, ferroptosis is significantly enhanced by CACG in vivo. Moreover, elevated oxidative stress triggers robust immune responses by promoting dendritic cells maturation and T cell infiltration. The in vivo results prove that CACG could efficiently inhibit tumor growth in 4T1 tumor-bearing mouse model without causing obvious systemic toxicity, suggesting the great potential of CACG in enhancing ferroptosis and immunotherapy for effective cancer treatment.
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Ferroptosis , Nanopartículas , Neoplasias , Animales , Ratones , Cobre , Especies Reactivas de Oxígeno , Inmunoterapia , Glucosa Oxidasa , Glutatión , Peróxido de Hidrógeno , Microambiente Tumoral , Línea Celular Tumoral , Neoplasias/terapiaRESUMEN
The chemotherapy efficacy of nanodrugs is restricted by poor tumor targeting and uptake. Here, an engineered biohybrid living material (designated as EcN@HPB) is constructed by integrating paclitaxel and BAY-876 bound human serum albumin nanodrugs (HPB) with Escherichia coli Nissle 1917 (EcN). Due to the inherent tumor tropism of EcN, EcN@HPB could actively target the tumor site and competitively deprive glucose through bacterial respiration. Thus, albumin would be used as an alternative nutrient source for tumor metabolism, which significantly promotes the internalization of HPB by tumor cells. Subsequently, BAY-876 internalized along with HPB nanodrugs would further depress glucose uptake of tumor cells via inhibiting glucose transporter 1 (GLUT1). Together, the decline of glucose bioavailability of tumor cells would activate and promote the macropinocytosis in an AMP-activated protein kinase (AMPK)-dependent manner, resulting in more uptake of HPB by tumor cells and boosting the therapeutic outcome of paclitaxel.
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Infecciones por Escherichia coli , Nanopartículas , Neoplasias , Humanos , Disponibilidad Biológica , Escherichia coli/genética , Escherichia coli/metabolismo , Glucosa/metabolismo , Nanopartículas/uso terapéutico , Neoplasias/tratamiento farmacológico , Paclitaxel/farmacología , Paclitaxel/uso terapéuticoRESUMEN
The differential tumor environment guides various antitumor drug delivery strategies for efficient cancer treatment. Here, based on the special bacteria-enriched tumor environment, we report a different drug delivery strategy by targeting bacteria inhabiting tumor sites. With a tissue microarray analysis, it was found that bacteria amounts displayed significant differences between tumor and normal tissues. Bacteria-targeted mesoporous silica nanoparticles decorated with bacterial lipoteichoic acid (LTA) antibody (LTA-MSNs) could precisely target bacteria in tumors and deliver antitumor drugs. By the intravenous administration of bacteria-targeted nanoparticles, we showed in mice with colon cancer, lung cancer, and breast cancer that LTA-MSNs exhibited a high tumor-targeting ability. As a proof-of-concept study, tumor microbes as some of the characteristics of a tumor environment could be utilized as potential targets for tumor targeting. This bacteria-guided tumor-targeting strategy might have great potential in differential drug delivery and cancer treatment.
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Antineoplásicos , Nanopartículas , Neoplasias , Ratones , Animales , Porosidad , Dióxido de Silicio/uso terapéutico , Sistemas de Liberación de Medicamentos , Nanopartículas/uso terapéutico , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Bacterias , Portadores de Fármacos/uso terapéuticoRESUMEN
Clinical treatment efficacy of oral bacterial therapy has been largely limited by insufficient gut retention of probiotics. Here, we developed a bioorthogonal-mediated bacterial delivery strategy for enhancing probiotics colonization by modulating bacterial adhesion between probiotics and gut inhabitants. Metabolic amino acid engineering was applied to metabolically incorporate azido-decorated d-alanine into peptidoglycans of gut inhabitants, which could enable in situ bioorthogonal conjugation with dibenzocyclooctyne (DBCO)-modified probiotics. Both in vitro and in vivo studies demonstrated that the occurrence of the bioorthogonal reaction between azido- and DBCO-modified bacteria could result in obvious bacterial adhesion even in a complex physiological environment. DBCO-modified Clostridium butyricum (C. butyricum) also showed more efficient reservation in the gut and led to obvious disease relief in dextran sodium sulfate-induced colitis mice. This strategy highlights metabolically modified gut inhabitants as artificial reaction sites to bind with DBCO-decorated probiotics via bioorthogonal reactions, which shows great potential for enhancing bacterial colonization.
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Gut microbiota play an important role in the pathophysiology of type 2 diabetic mellitus (T2DM) and biodisposition of drugs. Our previous study demonstrated that T2DM rats had the decreased plasma exposure of clopidogrel active metabolite (Clop-AM) due to upregulation of P-glycoprotein (P-gp). However, whether the change to clopidogrel (Clop) disposition under T2DM condition is associated with gut microbiota needs to be elucidated. In the study, we used an antibiotic cocktail consisting of ampicillin, vancomycin, metronidazole, and neomycin to disrupt gut microbiota and observed their influence on pharmacokinetic profiles of Clop-AM. Antibiotic administration markedly alleviated T2DM rats' phenotype including hyperglycemia, insulin resistance, oxidative stress, inflammation, hyperlipidemia, and liver dysfunction. Meanwhile, treatment with antibiotics significantly reversed the reduced systemic exposure of Clop-AM in T2DM rats relative to control rats, which was associated with the decreased intestinal P-gp level that might promote Clop absorption, resulting in more Clop transformation to Clop-AM. Fecal microbiome analysis exhibited a serious disruption of gut microbiota after antibiotic treatment with the sharply reduced microbial load and the altered microbial composition. Interestingly, an in vitro study showed that antibiotics had no influence on P-gp mRNA leve in SW480 cells, suggesting the microbiome disruption, not the direct role of antibiotics on P-gp expression, contributes to the altered P-gp level and Clop disposition in T2DM rats. The findings add new insights into the potential impact of gut microbiota on Clop biodisposition. Significance Statement 1.Antibiotics increase systemic exposure of Clop-AM in T2DM rats, which is associated with the downregulation of P-gp level.2.Antibiotics-induced disruption of gut microbiota, not direct effect of antibiotics on P-gp and CYPs expression, contributes to the altered Clop disposition.3.Antibiotics also alleviate T2DM phenotype including hyperglycemia, hyperlipidemia, insulin resistance, liver dysfunction and inflammation.
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Human visual behavior on a product significantly affects their purchasing behavior during online shopping. In this study, two experimental studies were performed to investigate human visual behavior and preference for sneakers using an eye tracking technology. The first study discovered that shoelace and vamp areas of interests (AOIs) attracted more attention than the other AOIs. The second study explored the factors affecting human behavior on sneakers, which employed 30 students from different professional backgrounds (i.e., such as fashion and non-fashion disciplines), and examined 24 sneakers, i.e., combinations of four shoelace styles and six vamp materials. The results showed that both genders irrespective of their professional backgrounds were more concerned about the shoelaces than vamps. The shoelace AOI gained more attention of females than males, while the vamp AOI was more concerned by males than females. The vamp AOI was more concerned by non-professionals than professionals, while the shoelace AOI was paid more attention by professionals than non-professionals. Besides, flat or round shoelaces, canvas, and cow leather or cotton flannel vamp materials were more preferred by the participants than the other types. The findings are of great help for the fashion product designers, the manufacturers, and the sellers to provide the product required by the customers.
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Because a host's immune system is affected by host-microbiota interactions, means of modulating the microbiota could be leveraged to augment the effectiveness of cancer therapies. Here we report that patients with oral squamous cell carcinoma (OSCC) whose tumours contained higher levels of bacteria of the genus Peptostreptococcus had higher probability of long-term survival. We then show that in mice with murine OSCC tumours injected with oral microbiota from patients with OSCCs, antitumour responses were enhanced by the subcutaneous delivery of an adhesive hydrogel incorporating silver nanoparticles (which inhibited the growth of bacteria competing with Peptostreptococcus) alongside the intratumoural delivery of the bacterium P. anaerobius (which upregulated the levels of Peptostreptococcus). We also show that in mice with subcutaneous or orthotopic murine OSCC tumours, combination therapy with the two components (nanoparticle-incorporating hydrogel and exogenous P. anaerobius) synergized with checkpoint inhibition with programmed death-1. Our findings suggest that biomaterials can be designed to modulate human microbiota to augment antitumour immune responses.
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Microbiota , Neoplasias de la Boca , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Carcinoma de Células Escamosas de Cabeza y Cuello , Animales , Materiales Biocompatibles , Humanos , Nanopartículas del Metal , Ratones , Boca/microbiología , Neoplasias de la Boca/tratamiento farmacológico , Neoplasias de la Boca/inmunología , Peptostreptococcus/efectos de los fármacos , Plata , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello/inmunologíaRESUMEN
The excessive lactate in the tumor microenvironment always leads to poor therapeutic outcomes of chemotherapy. In this study, a self-driven bioreactor (defined as SO@MDH, where SO is Shewanella oneidensis MR-1 and MDH is MIL-101 metal-organic framework nanoparticles/doxorubicin/hyaluronic acid) is rationally constructed via the integration of doxorubicin (DOX)-loaded metal-organic framework (MOF) MIL-101 nanoparticles with SO to sensitize chemotherapy. Owing to the intrinsic tumor tropism and electron-driven respiration of SO, the biohybrid SO@MDH could actively target and colonize hypoxic and eutrophic tumor regions and anaerobically metabolize lactate accompanied by the transfer of electrons to Fe3+, which is the key component of the MIL-101 nanoparticles. As a result, the intratumoral lactate would undergo continuous catabolism coupled with the reduction of Fe3+ to Fe2+ and the subsequent degradation of MIL-101 frameworks, leading to an expeditious drug release for effective chemotherapy. Meanwhile, the generated Fe2+ will be promptly oxidized by the abundant hydrogen peroxide in the tumor microenvironment to reproduce Fe3+, which is, in turn, beneficial to circularly catabolize lactate and boost chemotherapy. More importantly, the consumption of intratumoral lactic acid could significantly inhibit the expression of multidrug resistance-related ABCB1 protein (also named P-glycoprotein (P-gp)) for conquering drug-resistant tumors. SO@MDH demonstrated here holds high tumor specificity and promising chemotherapeutic efficacy for suppressing tumor growth and overcoming multidrug resistance, confirming its potential prospects in cancer therapy.
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Estructuras Metalorgánicas , Nanopartículas , Neoplasias , Humanos , Doxorrubicina/farmacología , Neoplasias/terapia , Reactores Biológicos , Lactatos , Microambiente TumoralRESUMEN
Triethanolamine (TEA), triisopropanolamine (TIPA), diethanol isopropanolamine (DEIPA) are necessary cement additives, and knowing their contents is needed for quality control and also to understand final properties of the cement. Whether it is the production of grinding aids, technical research and development or application research all involve the detection of grinding aids. This work developed a simple analytical technique for the simultaneous analysis of these alkanolamines in liquid cement grinding aids using high-performance liquid chromatography (HPLC) combined with evaporative light scattering detection (ELSD). HPLC was conducted by an XBridge C18 column (with dimensions 4.6 × 250 mm and 5 µm particles) using methanol and 0.1% trichloroacetic acid as mobile elution phases. The ELSD sprayer and drift tube temperatures were 60 ºC and 90 ºC, respectively. HPLC-ELSD developed in this work demonstrated 1) high sensitivity with limits of detection for the three analytes are 0.15, 0.54, 1.04 µg/mL; 2) good linearity with correlation coefficients equal to 0.997-0.999 over the tested concentration range; 3) excellent repeatability with intra- and interday coefficient of variation (CV) below 2.71% and 4, satisfactory accuracy with recovery in the 95.5%-100.8% range. This novel method is a powerful, time- and costeffective tool for alkanolamine analyses and quality control.
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Accumulating evidence indicates that colonized microbes play a crucial role in regulating health and disease in the human body. Detecting microbes should be essential for understanding the relationship between microbes and diseases, as well as increasing our ability to detect diseases. Here, a combined metabolic labeling strategy was developed to identify different bacterial species and microbiota by the use of three different fluorescent metabolite derivatives emitting red, green, and blue (RGB) fluorescence. Upon co-incubation with microbes, these fluorescent metabolite derivatives are incorporated into bacteria, generating unique true-color fingerprints for different bacterial species and different microbiota. A portable spectrometer was also fabricated to automate the colorimetric analysis in combination with a smartphone to conveniently identify different bacterial species and microbiota. Herein, the effectiveness of this system was demonstrated by the identification of certain bacterial species and microbiota in mice with different diseases, such as skin infections and bacteremia. By analyzing the microbiota fingerprints of saliva samples from clinical patients and healthy people, this system was proved to precisely distinguish oral squamous cell carcinoma (OSCC, n = 29) samples from precancerous (n = 10) and healthy (n = 5) samples.
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Global alterations in the metabolic network provide substances and energy to support tumor progression. To fuel these metabolic processes, extracellular matrix (ECM) plays a dominant role in supporting the mass transport and providing essential nutrients. Here, we report a fibrinogen and thrombin based coagulation system to construct an artificial ECM (aECM) for selectively cutting-off the tumor metabolic flux. Once a micro-wound is induced, a cascaded gelation of aECM can be triggered to besiege the tumor. Studies on cell behaviors and metabolomics reveal that aECM cuts off the mass transport and leads to a tumor specific starvation to inhibit tumor growth. In orthotopic and spontaneous murine tumor models, this physical barrier also hinders cancer cells from distant metastasis. The in vivo gelation provides an efficient approach to selectively alter the tumor mass transport. This strategy results in a 77% suppression of tumor growth. Most importantly, the gelation of aECM can be induced by clinical operations such as ultrasonic treatment, surgery or radiotherapy, implying this strategy is potential to be translated into a clinical combination regimen.
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Materiales Biomiméticos/administración & dosificación , Matriz Extracelular/química , Neoplasias/terapia , Animales , Transporte Biológico/efectos de los fármacos , Transporte Biológico/efectos de la radiación , Materiales Biomiméticos/química , Materiales Biomiméticos/efectos de la radiación , Línea Celular Tumoral/trasplante , Proliferación Celular/efectos de los fármacos , Proliferación Celular/efectos de la radiación , Quimioradioterapia/métodos , Modelos Animales de Enfermedad , Matriz Extracelular/metabolismo , Matriz Extracelular/efectos de la radiación , Femenino , Fibrinógeno/administración & dosificación , Fibrinógeno/química , Fibrinógeno/efectos de la radiación , Geles , Humanos , Inyecciones Intravenosas , Metabolómica , Ratones , Neoplasias/metabolismo , Trombina/administración & dosificación , Trombina/química , Trombina/efectos de la radiación , Terapia por Ultrasonido/métodos , Ondas UltrasónicasRESUMEN
A novel design of personal cooling clothing incorporating additional insulation sandwiched between phase change materials (PCMs) and clothing outer layer is proposed. Performance of four personal cooling systems including clothing with only PCMs, clothing with PCMs and insulation (PCM + INS), clothing with PCMs and ventilation fans (HYB), and clothing with PCMs, ventilation fans and insulation (HYB + INS) was investigated. Effect of additional insulation on clothing cooling performance in terms of human physiological and perceptual responses was also examined. Human trials were carried out in a hot environment (i.e. 36 °C, RH = 59%). Results showed that significantly lower mean skin/torso temperatures were registered in HYB + INS as compared to HYB. In contrast, no significant effect of the use of insulation on both skin and body temperatures between PCM and PCM + INS was observed. Also, no significant difference in thermal sensations, thermal comfort, and skin wetness sensation was registered between cooling systems with and without additional insulation. Practitioner Summary: Hybrid personal cooling clothing has shown the ability to provide a relatively cool microclimate around the wearer' body while working in hot environments. The present work addresses the importance of cooling energy saving for PCMs in a hot environment. This work contributes to optimising cooling performance of hybrid personal cooling systems.
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Regulación de la Temperatura Corporal , Frío , Trastornos de Estrés por Calor/prevención & control , Ropa de Protección , Adulto , Prueba de Esfuerzo , Frecuencia Cardíaca , Humanos , Masculino , Microclima , Temperatura Cutánea , Sudoración , Adulto JovenRESUMEN
Many documented studies have demonstrated the human mortality rate increases during severe heatwaves. There remains a need for further explore ecologically valid cooling strategies to alleviate body heat strain during extreme heatwaves. The main aim of this work was to explore whether intermittent wetting clothing can be served as an ecologically valid cooling strategy to mitigate heat stress on inactive vulnerable populations not having access to air-conditioning during a severe heatwave. Ten young male subjects underwent two 90-min separate trials: a dry clothing trial (i.e., CON) and a wetted clothing cooling trial (i.e., WEC). A set of light summer wear was chosen and intermittently wetted by tap water at intervals of every 30â¯min. Physiological and perceptual responses of subjects were examined and compared. All trials were performed in a chamber with an air temperature of 43⯱â¯0.5⯰C, RH=â¯57⯱â¯5% and an air velocity of 0.15⯱â¯0.05â¯m/s (WBGT=37.35⯰C). Results demonstrated that WEC, compared with CON, could significantly reduce both the mean skin temperature and the core temperature throughout the 5-90th min and 25-90th min of the trial, respectively (pâ¯<â¯0.05). Besides, WEC could also remarkable reduce local skin temperatures at those body sites covered by wet clothing (pâ¯<â¯0.05). In comparison, no significant difference was found between WEC and CON on perceptual responses. Further, it was also found from PHS simulations that conditions with a partial water vapour pressure ≤â¯3.1-3.5â¯kPa would not induce pronounced core temperature rises at 43⯰C. Finally, it may be concluded that intermittent wetting clothing could be served as an ecologically valid cooling strategy to reduce thermophysiological strain of vulnerable populations while seating during humid heatwaves and thereby improve their health and safety.
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Regulación de la Temperatura Corporal , Trastornos de Estrés por Calor/prevención & control , Ropa de Protección/normas , Humectabilidad , Adulto , Calor/efectos adversos , Humanos , Masculino , Distribución Aleatoria , Temperatura CutáneaRESUMEN
Chan, APC, Yang, Y, Wong, FKW, Yam, MCH, Wong, DP, and Song, W-F. Reduction of physiological strain under a hot and humid environment by a hybrid cooling vest. J Strength Cond Res 33(5): 1429-1436, 2019-Cooling treatment is regarded as one of good practices to provide safe training conditions to athletic trainers in the hot environment. The present study aimed to investigate whether wearing a commercial lightweight and portable hybrid cooling vest that combines air ventilation fans with frozen gel packs was an effective means to reduce participants' body heat strain. In this within-subject repeated measures study, 10 male volunteers participated in 2 heat-stress trials (one with the cooling vest-COOL condition, and another without-CON condition, in a randomized order) inside a climatic chamber with a controlled ambient temperature 33° C and relative humidity (RH) 75% on an experimental day. Each trial included a progressively incremental running test, followed by a 40-minute postexercise recovery. Core temperature (Tc), heart rate (HR), sweat rate (SR), rating of perceived exertion (RPE), exercise duration, running distance, and power output were measured. When comparing the 2 conditions, a nonstatistically significant moderate cooling effect in rate of increase in Tc (0.03 ± 0.02° C·min for COOL vs. 0.04 ± 0.02° C·min for CON, p = 0.054, d = 0.57), HR (3 ± 1 b·min·min for COOL vs. 4 ± 1 b·min·min for CON, p = 0.229, d = 0.40), and physiological strain index (PSI) (0.20 ± 0.06 unit·min for COOL vs. 0.23 ± 0.06 unit·min for CON, p = 0.072, d = 0.50) was found in the COOL condition during exercise. A nonstatistically significant (p > 0.05) trivial cooling effect (d < 0.2) was observed between the COOL and CON conditions for measures of exercise duration, running distance, power output, SR, and RPE. It is concluded that the use of the hybrid cooling vest achieved a moderate cooling effect in lowering the rate of increase in physiological strain without impeding the performance of progressively incremental exercise in the heat.
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Regulación de la Temperatura Corporal/fisiología , Crioterapia/métodos , Calor , Humedad , Ropa de Protección , Adolescente , Adulto , Atletas , Temperatura Corporal/fisiología , Diseño de Equipo , Ejercicio Físico/fisiología , Frecuencia Cardíaca/fisiología , Trastornos de Estrés por Calor , Humanos , Masculino , Esfuerzo Físico/fisiología , Carrera/fisiología , Temperatura Cutánea , Sudoración/fisiología , Adulto JovenRESUMEN
Humification plays a critical role in the environmental fate of organic wastes, and MnO2 holds great promise for enhancing this reaction. However, the effects of MnO2 on the enhancement of the humification reaction remain ambiguous. To better reveal the mechanism by which MnO2 enhances the reaction and investigate the fate of the humification products, abiotic humification experiments were performed using increasing concentrations of dissolved organic matter (DOM) to a fixed amount of MnO2. DOM was represented by model humic precursors consisting of catechol, glucose and glycine. The results indicate that the reduction of MnO2 played a dominant role in the formation of fulvic-like acids (FLAs), and the subsequent reduction products, MnOOH and Mn(II), acted as catalysts in the formation of humic-like acids (HLAs). Moreover, CO2 release occurred during the formation of FLAs, and a strong linear correlation between CO2 release and the formation of FLAs was observed (pâ¯<â¯0.01), where 0.73-1.87â¯mg of CO2 was released per mg dissolved organic carbon (DOC) FLAs. Furthermore, the concentration of MnO2 had a pronounced influence on the product behavior, where a lower MnO2 concentration decreased the quantity of FLAs produced.
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Sustancias Húmicas , Compuestos de Manganeso/química , Óxidos/química , Dióxido de Carbono/química , Catálisis , Cinética , Oxidación-ReducciónRESUMEN
A star-shaped molecularly imprinted coating was prepared starting from octavinyl-modified polyhedral oligomeric silsesquioxanes (Ov-POSS). It possesses a relatively open structure and has good site accessibility and a larger capacity even at lower cross-linking. The imprinted coating was prepared from S-amlodipine (S-AML) as the template and analyte, Ov-POSS as the cross-linker, and methacrylic acid as the functional monomer. The preparation and chromatographic parameters were optimized, including ratio of template to functional monomer, apparent cross-linking degree, pH value, ACN content and salt concentration in the mobile phase. The best resolution in enantiomer separation by means of capillary electrochromatography reaches a value of 33. A good recognition ability (α = 2.60) was obtained and the column efficiency for S-AML was 54,000 plates m-1. The use of Ov-POSS as a cross-linker significantly improves the column capacity and thus the detection sensitivity. The results show that Ov-POSS is an effective cross-linker for the preparation of imprinted polymers with good accessibility and large capacity. Graphical abstract Schematic presentation of the preparation of star-shaped imprinted polymer using octavinyl-modified polyhedral oligomeric silsesquioxanes (Ov-POSS) and by using methacrylic acid (MAA) as functional monomer. The best enantiometric resolution (33) for amlodipine (AML) can be achieved in capillary chromatography (CEC).
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An inorganic-organic hybrid monolith incorporated with stellated mesoporous silica nanoparticles (SMSNs) was prepared. Using binary solvents, deep eutectic solvents and room temperature ionic liquids, an SMSN-incorporated poly(butyl methacrylate-co-ethylene glycol dimethacrylate) monolith demonstrated uniform structure with good column permeability. A systematic investigation of preparation parameter was performed, including SMSN content, crosslinking monomer content, and the component of binary solvent. The optimized monoliths were characterized by field emission scanning electron microscopy, transmission electron microscopy, area scanning energy dispersive spectrometry, and nitrogen adsorption. Column performance was tested by separating four groups of analytes (alkylbenzenes, anilines, naphthalenes and phenols) by capillary electrochromatography (CEC). Baseline separation of all analytes was obtained with column efficiencies of up to 266,000 plates m-1. The performance of the resulting monolith was further investigated in detail by separating mixtures of polycyclic aromatic hydrocarbons (PAHs), nonsteroidal antiinflammatory drugs (NSAIDs), and hydroxybenzoic acid isomers. Compared with the corresponding SMSN-free monolith, the CEC performance was improved by about six times. Successful extraction of PAHs and quinolones (QNs) were also performed using this capillary. Improved extraction efficiency (20.2%) for complex samples, lake water, was also found when the material was applied to solid phase microextraction of fluoranthene. Graphical abstract A poly(butyl methacrylate-co-ethylene glycol dimethacrylate) monolith incorporated with stellated mesoporous silica nanoparticles was prepared. It demonstrated column efficiency up to 266,000 plates m-1 in capillary electrochromatography and ability as solid phase microextraction for organic small molecules with good column permeability.