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Chlorine has been proven to promote the volatilization of heavy metals during sludge combustion. This work compared the migration of heavy metals with NaCl addition under different combustion modes at 900 â. The combustion modes have less effect on the mineral phase of residues, but the volatilization and toxicity reduction of heavy metals were more pronounced under isothermal combustion. The mineral evolution, release of Cl, and migration of metals were dynamically tracked by the continuous sampling at different combustion time under isothermal combustion. It was found that the volatile matter and fixed carbon burned almost simultaneously, and the addition of NaCl promoted them. As combustion proceeded, the minerals gradually crystallized and the heavy metals were volatilized due to the direct and indirect chlorination. Meanwhile, the chlorination and volatilization of Zn was less than that of Pb due to its effective solidification by minerals. The combination of the adsorption by exposed char and solidification by sludge minerals influenced the dynamic leaching behavior of metals. These results will help understand the interactions between heavy metals, inorganic Cl, and Fe-Si-Al minerals during combustion, which will further help optimize the combustion strategy for both stabilization or enrichment of heavy metals when inorganic chlorine exists.
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The sound disposal of the ensuing heavy metal-rich plants can address the aftermath of phytoremediation. In this study, the first attempt was made to obtain heavy metals-free and phosphorus-rich biochar from phytoremediation residue (PR) by pyrolysis, and the effects of chlorinating agent type, chlorine dosage, and pyrolysis residence time on heavy metal removal, phosphorus (P) transformation, and biochar properties were investigated. The results showed that as chlorine dosage and pyrolysis residence time increased, added polyvinyl chloride (PVC) reduced the concentration of Zn in biochar to one-tenth of that in PR by intensified chlorination, where both Zn concentration (2727.50 mg/kg) and its leaching concentration (29.13 mg/L) met the utilization requirements, in which the acid-base property of biochar plays a key role in heavy metal leaching. Meanwhile, more than 90% of P in PR remained in biochar and the bioavailability of P in biochar enhanced with the decomposition of organic P to inorganic P, where the concentration of plant-availability P (Pnac) expanded from 1878.40 mg/kg in PR to 8454.00 mg/kg in biochar. This study demonstrated that heavy metal hyperaccumulator can be converted into heavy metal-free and phosphorus-rich biochar with promising applications, which provides new perspectives for the treatment of such hazardous wastes.
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Metales Pesados , Fósforo , Cloro , Pirólisis , Metales Pesados/química , Carbón Orgánico/químicaRESUMEN
SO2 can noticeably impact the control of high toxic selenium emissions from flue gas by CaO. Surprisingly, our experiments showed that under certain conditions, SO2 can promote selenium capture by CaO, rather than hinder it. To elucidate the underlying mechanism, a combination of theoretical calculations and experiments was conducted. Thermodynamic equilibrium analysis revealed that gaseous SO2 and solid Ca-S reaction products can promote SeO2 converting to SeO/Se0. The Ca-S products facilitated greater SeO2 conversion compared to SO2. Experimental results demonstrated that selenium adsorption capacity of incompletely sulfurized CaO (CaO with pre-adsorbed SO2) was higher than that of completely sulfurized CaO (Ca-S products), highlighting the importance of adsorption sites of CaO. Density functional theory calculations showed that the pre-adsorbed SO2 hardly affected selenium adsorption energy on the SO2/CaO surface, while completely sulfurized CaO had low selenium adsorption energy, explaining the experimental phenomenon and proving necessary of CaO. Additionally, SeO/Se0 had higher adsorption energy on CaO than SeO2. Overall, the promotion of SO2 on selenium adsorption was primarily affected by two factors: 1) sulfur facilitating SeO2 conversion to SeO/Se0 which can be adsorbed more easily by CaO; 2) sufficient adsorption sites on CaO surface existing for SeO/Se0 adsorption, despite co-adsorption with sulfur.
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Mesenchymal stromal cell-derived extracellular vesicles (MSC-EVs) are extremely promising nanoscale cell-free therapeutic agents. We previously identified that intravenous administration (IV) of human umbilical cord MSC-EVs (hUCMSC-EVs), especially hypoxic hUCMSC-EVs (Hypo-EVs), could suppress allergic airway inflammation and remodeling. Here, we further investigated the therapeutic effects of Hypo-EVs administration by atomizing inhalation (INH), which is a non-invasive and efficient drug delivery method for lung diseases. We found that nebulized Hypo-EVs produced by the atomization system (medical/household air compressor and nebulizer) maintained excellent structural integrity. Nebulized Dir-labeled Hypo-EVs inhaled by mice were mainly restricted to lungs. INH administration of Hypo-EVs significantly reduced the airway inflammatory infiltration, decreased the levels of IL-4, IL-5 and IL-13 in bronchoalveolar lavage fluid (BALF), declined the content of OVA-specific IgE in serum, attenuated the goblet cell metaplasia, and the expressions of subepithelial collagen-1 and α-smooth muscle actin (α-SMA). Notably, Hypo-EV INH administration was generally more potent than Hypo-EV IV in suppressing IL-13 levels and collagen-1 and α-SMA expressions. RNA sequencing revealed that various biological processes, such as cell adhesion, innate immune response, B cell activation, and extracellular space, were associated with the activity of Hypo-EV INH against asthma mice. In addition, Hypo-EVs could load exogenous miR-146a-5p (miR-146a-5p-EVs). Furthermore, INH administration of miR-146a-5p-EVs resulted in a significantly increased expression of miR-146a-5p mostly in lungs, and offered greater protection against the OVA-induced increase in airway inflammation, subepithelial collagen accumulation and myofibroblast compared with nebulized Hypo-EVs. Overall, nebulized Hypo-EVs effectively attenuated allergic airway inflammation and remodeling, potentially creating a non-invasive route for the use of MSC-EVs in asthma treatment.
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Asma , Vesículas Extracelulares , MicroARNs , Humanos , Animales , Ratones , Interleucina-13 , Inflamación/terapia , Vesículas Extracelulares/metabolismo , Colágeno Tipo I , Colágeno/metabolismo , Hipoxia , MicroARNs/genética , MicroARNs/uso terapéuticoRESUMEN
The emission of semi-volatile heavy metals during the thermal utilization of various fuels has been a huge threat to the environment. In this study, the montmorillonite modified by thermal treatment and hydrochloric acid activation was evaluated for the PbCl2 adsorption performance. The optimum adsorption temperature of sorbents increased with the thermal treatment temperature (<500 °C) for the increased amount of reactive sites caused by the removal of interlayer water and hydroxyl, while a higher treatment temperature will collapse the lamellar structure of montmorillonite and greatly inhibit the PbCl2 adsorption. Besides, the hydrochloric acid activation can help inhibit the melting of sorbents during the adsorption process by removing the impurities and promote the PbCl2 vapor to contact with more reactive sites at higher temperatures. By comparing different sorbents, montmorillonite was found to exhibit better adsorption performance at 600-700 °C, while the sorbent thermal-treated at 500 °C and then acid-activated got the highest adsorption efficiency at 900 °C, which was 17.83% higher than that of montmorillonite. This study provided an environmental-friendly modification method to capture more heavy metals at high-temperature conditions, which can be partly realized by the recycling of montmorillonite used for the removal of normal gas pollutants in lower temperatures conditions or acid wastewater treatment.
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Bentonita , Metales Pesados , Temperatura , Bentonita/química , Gases , Adsorción , Ácido Clorhídrico , Metales Pesados/químicaRESUMEN
Si/Al-based adsorbents are effective adsorbents for capturing heavy metals in incineration flue gases at high temperatures in the furnace. In this work, the adsorption characteristics and adsorption mechanisms of Si/Al-based adsorbents for lead and cadmium vapors were studied using a combination of experimental and density functional theory (DFT) calculations. The trapping performance of a series of Si/Al-based adsorbents for Pb and Cd vapors was investigated using a self-designed gas-solid two-phase rapid adsorption experimental system. The results showed that kaolinite and montmorillonite exhibited better heavy metal adsorption capacity than SiO2 and Al2O3, and were significantly stronger for Pb than for Cd. Chemisorption dominated the capture of Pb/Cd by Si/Al-based adsorbents at high temperatures. The results of DFT calculations indicated that the chemisorption mechanisms dominated the adsorption of Pb and Cd species on the metakaolinite (001) surface, and the adsorption energy of Pb species on the metakaolinite surface was greater than that of Cd species. The exposed O atoms and unsaturated Al atoms of metakaolinite (001) surface were effective adsorption active sites for heavy metals and their chlorides. In the adsorption reaction, the binding of Pb/Cd atoms and surface exposed O sites, as well as the strong interaction between Cl and unsaturated Al atoms, were responsible for the capture of Pb and Cd chlorides by metakaolinite.
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Incineración , Metales Pesados , Cadmio/química , Adsorción , Plomo , Dióxido de Silicio , Cloruros , Gases/química , Metales Pesados/química , Modelos TeóricosRESUMEN
PURPOSE: Training deep neural networks usually require a large number of human-annotated data. For organ segmentation from volumetric medical images, human annotation is tedious and inefficient. To save human labour and to accelerate the training process, the strategy of annotation by iterative deep learning recently becomes popular in the research community. However, due to the lack of domain knowledge or efficient human-interaction tools, the current AID methods still suffer from long training time and high annotation burden. METHODS: We develop a contour-based annotation by iterative deep learning (AID) algorithm which uses boundary representation instead of voxel labels to incorporate high-level organ shape knowledge. We propose a contour segmentation network with a multi-scale feature extraction backbone to improve the boundary detection accuracy. We also developed a contour-based human-intervention method to facilitate easy adjustments of organ boundaries. By combining the contour-based segmentation network and the contour-adjustment intervention method, our algorithm achieves fast few-shot learning and efficient human proofreading. RESULTS: For validation, two human operators independently annotated four abdominal organs in computed tomography (CT) images using our method and two compared methods, i.e. a traditional contour-interpolation method and a state-of-the-art (SOTA) convolutional network (CNN) method based on voxel label representation. Compared to these methods, our approach considerably saved annotation time and reduced inter-rater variabilities. Our contour detection network also outperforms the SOTA nnU-Net in producing anatomically plausible organ shape with only a small training set. CONCLUSION: Taking advantage of the boundary shape prior and the contour representation, our method is more efficient, more accurate and less prone to inter-operator variability than the SOTA AID methods for organ segmentation from volumetric medical images. The good shape learning ability and flexible boundary adjustment function make it suitable for fast annotation of organ structures with regular shape.
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Aprendizaje Profundo , Humanos , Redes Neurales de la Computación , Tomografía Computarizada por Rayos X/métodos , Algoritmos , Procesamiento de Imagen Asistido por Computador/métodosRESUMEN
Serious pollution is caused by heavy metals (HMs) emission during sludge combustion treatment, but the addition of minerals has the ability to alleviate the migration of HMs to the gaseous state. In this study, HMs (As, Cr, Zn and Cu) behavior, speciation, and environmental risk during sludge combustion with CaO and montmorillonite (MMT) additive was investigated in the lab-scale tube furnace. The results showed that the sludge combustion was mainly determined by volatile matter. In general, CaO inhibited the volatilization of Cr, Zn, and Cu, but promoted As volatilization. MMT inhibited the volatilization of HMs, but the effect was not obvious at high temperatures. Besides, the improvement of retention effect was not found for Cr and Cu with the increase of CaO at 1000 °C, there might exist threshold value for CaO on HMs retention process. Meanwhile, CaO increased acid-soluble fraction of As significantly at high temperatures, decreased residual fraction of Cr by oxidation, converted Zn and Cu to residual fraction. MMT increased the acid-soluble fraction of As and residual fraction of Cr. In view of the HMs environmental risk in ash, the combustion temperature of sludge was necessary to control under 1000 °C and minerals additive amount was needed to manage above 1000 °C.
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Metales Pesados , Aguas del Alcantarillado , Bentonita , Contaminación Ambiental , Metales Pesados/análisisRESUMEN
The development of medical image analysis algorithm is a complex process including the multiple sub-steps of model training, data visualization, human-computer interaction and graphical user interface (GUI) construction. To accelerate the development process, algorithm developers need a software tool to assist with all the sub-steps so that they can focus on the core function implementation. Especially, for the development of deep learning (DL) algorithms, a software tool supporting training data annotation and GUI construction is highly desired. In this work, we constructed AnatomySketch, an extensible open-source software platform with a friendly GUI and a flexible plugin interface for integrating user-developed algorithm modules. Through the plugin interface, algorithm developers can quickly create a GUI-based software prototype for clinical validation. AnatomySketch supports image annotation using the stylus and multi-touch screen. It also provides efficient tools to facilitate the collaboration between human experts and artificial intelligent (AI) algorithms. We demonstrate four exemplar applications including customized MRI image diagnosis, interactive lung lobe segmentation, human-AI collaborated spine disc segmentation and Annotation-by-iterative-Deep-Learning (AID) for DL model training. Using AnatomySketch, the gap between laboratory prototyping and clinical testing is bridged and the development of MIA algorithms is accelerated. The software is opened at https://github.com/DlutMedimgGroup/AnatomySketch-Software .
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Programas Informáticos , Interfaz Usuario-Computador , Humanos , Algoritmos , Inteligencia Artificial , Imagen por Resonancia Magnética/métodosRESUMEN
OBJECTIVES: To explore the optimal maintenance dose of caffeine citrate for preterm infants requiring assisted ventilation and caffeine citrate treatment. METHODS: A retrospective analysis was performed on the medical data of 566 preterm infants (gestational age ≤34 weeks) who were treated and required assisted ventilation and caffeine citrate treatment in the neonatal intensive care unit of 30 tertiary hospitals in Jiangsu Province of China between January 1 and December 31, 2019. The 405 preterm infants receiving high-dose (10 mg/kg per day) caffeine citrate after a loading dose of 20 mg/kg within 24 hours after birth were enrolled as the high-dose group. The 161 preterm infants receiving low-dose (5 mg/kg per day) caffeine citrate were enrolled as the low-dose group. RESULTS: Compared with the low-dose group, the high-dose group had significant reductions in the need for high-concentration oxygen during assisted ventilation (P=0.044), the duration of oxygen inhalation after weaning from noninvasive ventilation (P<0.01), total oxygen inhalation time during hospitalization (P<0.01), the proportion of preterm infants requiring noninvasive ventilation again (P<0.01), the rate of use of pulmonary surfactant and budesonide (P<0.05), and the incidence rates of apnea and bronchopulmonary dysplasia (P<0.01), but the high-dose group had a significantly increased incidence rate of feeding intolerance (P=0.032). There were no significant differences between the two groups in the body weight change, the incidence rates of retinopathy of prematurity, intraventricular hemorrhage or necrotizing enterocolitis, the mortality rate, and the duration of caffeine use (P>0.05). CONCLUSIONS: This pilot multicenter study shows that the high maintenance dose (10 mg/kg per day) is generally beneficial to preterm infants in China and does not increase the incidence rate of common adverse reactions. For the risk of feeding intolerance, further research is needed to eliminate the interference of confounding factors as far as possible.
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Cafeína , Respiración Artificial , Cafeína/uso terapéutico , Citratos , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Estudios RetrospectivosRESUMEN
Regression analysis of multivariate interval-censored failure time data has been discussed by many authors1-6. For most of the existing methods, however, one limitation is that they only apply to the situation where the censoring is non-informative or the failure time of interest is independent of the censoring mechanism. It is apparent that this may not be true sometimes and as pointed out by some authors, the analysis that does not take the dependent censoring into account could lead to biased or misleading results7,8. In this study, we consider regression analysis of multivariate interval-censored data arising from the additive hazards model and propose an estimating equation-based approach that allows for the informative censoring. The method can be easily implemented and the asymptotic properties of the proposed estimator of regression parameters are established. Also we perform a simulation study for the evaluation of the proposed method and it suggests that the method works well for practical situations. Finally, the proposed approach is applied to a set of real data.
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Proyectos de Investigación , Simulación por Computador , Modelos de Riesgos Proporcionales , Análisis de RegresiónRESUMEN
The high toxicity of Cr-Ca compounds generated during the heat treatment of solid waste will heavily threat the environment. In this work, a kind of Ca-rich river sludge which is bound with Ca and heavy metals was combusted with kaolin under 900 °C for 3 h in a muffle to study the transformation of Cr. The effects of kaolin on Cr transformation were investigated through sequential extraction, the risk assessment of heavy metals, and constant pH leaching test, also combined with crystal phase analysis of Ca-Al-Si minerals. The experimental results showed that the formation of Ca10(SiO4)3(SO4)3Cl2 was inhibited by the addition of 10% (mass fraction) kaolin and the released Cl promoted the evaporation of target elements in priority while 30% kaolin addition further inhibited the solidification of Cr. Furthermore, the effect of NaCl and CaCO3 on the Cr solidification by kaolin were also explored by leaching procedure or XRD analysis of calcination products of their mixtures. It should be noticed that the addition of kaolin in Cr2O3-CaCO3 mixture will directly react with CaCrO4 and fixed the generated Cr2O3 into internal layered structure, preventing its re-oxidization by the free CaO. This work aims to help illustrate the Cr transformation with existence of Ca during sintering of Ca-rich solid wastes and reduce the Cr contamination in future.
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Metales Pesados , Residuos Sólidos , Caolín , Metales Pesados/análisis , Aguas del AlcantarilladoRESUMEN
Twelve cinnamoyl glucoside derivatives were prepared by glycosylation of glucosyl trichloroacetimidate and cinnamic acid derivatives, followed by dechloroacetylation with a pyridine/H2O mixture. Their structures were characterized by 1H and 13C NMR, as well as mass analysis. All the products were tested for their antiproliferation activities against murine melanoma B16-F10 cell line. Compounds 4e-4j were able to inhibit the proliferation of murine melanoma B16-F10 cell line with IC50 values of 17.38 ± 0.07, 9.87 ± 0.09, 9.69 ± 0.12, 29.42 ± 0.04, 32.95 ± 0.08, 25.68 ± 0.09 µM, respectively.
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Glucósidos , Animales , Antineoplásicos , Línea Celular Tumoral , Melanoma Experimental , RatonesRESUMEN
Two new iridoid glycosides, genipin 1,10-di-O-α-l-rhamnoside (1) and genipin 1,10-di-O-ß-d-xylopyranoside (2), along with thirteen known compounds (3-15) were isolated from Gardeniae Fructus. Their structures were elucidated by physical data analyses such as NMR, UV, IR, HR-ESI-MS, as well as chemical hydrolysis. All compounds were tested for their tyrosinase inhibitory and antioxidant activities. At a concentration of 25 µM, compound 13 showed obvious mushroom tyrosinase inhibition activity with % inhibition value of 36.52 ± 1.98%, with kojic acid used as the positive control (46.09 ± 1.29%). At a concentration of 1 mM, compounds 8 and 9 exhibited considerable DPPH radical scavenging activities, with radical scavenging rates of 48.54 ± 0.47%, 58.59 ± 0.39%, respectively, with l-ascorbic acid used as the positive control (59.02 ± 0.77%).
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Inhibidores Enzimáticos/farmacología , Gardenia/química , Glicósidos Iridoides/farmacología , Monofenol Monooxigenasa/antagonistas & inhibidores , Agaricales/enzimología , Conformación de Carbohidratos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Glicósidos Iridoides/química , Glicósidos Iridoides/aislamiento & purificación , Monofenol Monooxigenasa/metabolismoRESUMEN
The pollution of semi-volatile heavy metals is one of the key environmental risks for municipal solid waste incineration, and in-situ adsorption of metals within the furnace by mineral sorbents such as kaolin has been demonstrated as a promising emission control method. To lessen the consumption of sorbent, a novel material of amorphous silicate was produced from kaolin through pressurised hydrothermal treatment. Its performance of gaseous PbCl2 capture was tested in a fixed bed furnace and compared with unmodified kaolin and metakaolin. With increasing temperature, the adsorption rates for all sorbents declined due to higher saturated vapour pressure, while the partitions of residual form lead increased which indicated higher stability of heavy metals in the sorbent because of melting effect. The new sorbent with a larger surface area and reformed structure presented 26% more adsorption efficiency than raw kaolin at 900⯰C, and increasing the modification pressure improved these properties. Additionally, the production of this high-temperature sorbent was relatively inexpensive, required little thermal energy and no chemicals to produce and no waste effluent was generated, thus being much cleaner than other modification methods.
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Asthma is a complex and heterogeneous inflammatory response characterized by various immune cells, including myeloid-derived suppressor cells (MDSCs) and CD4+ T-cell subsets. However, few studies on MDSC subsets and the association between MDSCs and CD4+ T-cell subsets in asthma are reported. In the present study, we detected CD4+ T cells and MDSC subsets and evaluated the relationship of these cells in mice with ovalbumin-induced asthma. We found that asthmatic mice showed severe airway inflammatory response and inflammatory cell infiltration in the lungs and bronchoalveolar lavage fluid. We also noted increased numbers of Th2, Th17, and MDSCs; decreased proportion of Th1 and Treg cells in the splenocytes and lungs; and increased expression of pro-inflammatory cytokines in splenocytes and lungs. Granulocytic MDSCs (G-MDSCs) and Th17 cells were closely related. Gemcitabine treatment reduced the G-MDSC level and the iNOS expression, alleviated the inflammatory response, and decreased the proportion and number of Th2 and Th17 cells in asthmatic mice. Besides the increase in Th2 and Th17 cells, the findings indicate that G-MDSC elevation plays a crucial role in asthmatic mice.
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Asma/inducido químicamente , Células Supresoras de Origen Mieloide/fisiología , Células Th17/fisiología , Animales , Citocinas , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/fisiología , Granulocitos , Pulmón/citología , Masculino , Ratones , Ratones Endogámicos BALB C , Ovalbúmina , Distribución Aleatoria , Bazo/citología , Linfocitos T ReguladoresRESUMEN
Two undescribed phenolic compounds, angelicols A (1) and B (2) and one undescribed coumarin rhamnoside, angelicoside A (3), together with 17 known compounds (4-20) were isolated from the roots of Angelica dahurica. Their structures were characterized by physical data analyses such as NMR, HRESIMS, and X-ray diffraction. Compounds 2, 3, 5, 6 and L-ascorbic acid (positive control) exhibited obvious DPPH radical scavenging activities with IC50 values of 0.36 mM, 0.43 mM, 0.39 mM, 0.44 mM, 0.25 mM, respectively. At a concentration of 25 µM, all compounds showed weaker tyrosinase inhibition activities (%inhibition < 5%) than kojic acid (26.00 ± 0.67%, IC50 = 44.29 ± 0.06 µM).
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Angelica/química , Antioxidantes/uso terapéutico , Cumarinas/química , Raíces de Plantas/química , Antioxidantes/farmacología , Monofenol Monooxigenasa/metabolismoRESUMEN
Helminths and their products can shape immune responses by modulating immune cells, which are dysfunctional in inflammatory diseases such as asthma. We previously identified SJMHE1, a small molecule peptide from the HSP60 protein of Schistosoma japonicum. SJMHE1 can inhibit delayed-type hypersensitivity and collagen-induced arthritis in mice. In the present study, we evaluated this peptide's potential intervention effect and mechanism on ovalbumin-induced asthma in mice. SJMHE1 treatment suppressed airway inflammation in allergic mice, decreased the infiltrating inflammatory cells in the lungs and bronchoalveolar lavage fluid, modulated the production of pro-inflammatory and anti-inflammatory cytokines in the splenocytes and lungs of allergic mice, reduced the percentage of Th2 cells and increased the proportion of Th1 and regulatory T cells (Tregs). At the same time, Foxp3 and T-bet expression increased, and GATA3 and RORγt decreased in the lungs of allergic mice. We proved that SJMHE1 can interrupt the development of asthma by diminishing airway inflammation in mice. The down-regulation of Th2 response and the up-regulation of Th1 and Tregs response may contribute to the protection induced by SJMHE1 in allergic mice. SJMHE1 can serve as a novel therapy for asthma and other allergic or inflammatory diseases.