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1.
Artigo em Inglês | MEDLINE | ID: mdl-33797947

RESUMO

Gummy stem blight (GSB), which is caused by three related species of Stagonosporopsis, is a worldwide devastating disease of cucurbit crops including watermelon. Previously S. cucurbitacearum was reported to be the major fungal cause of watermelon GSB in Southern China, where it causes a significant decrease in watermelon yield. Here, we present the draft whole genome sequence, gene prediction and annotation of S. cucurbitacearum strain DBTL4, isolated from diseased watermelon plants. To our knowledge, this is the first publicly available genome sequence of this species, and knowledge of this genome sequence will help further understand the pathogenic mechanism of S. cucurbitacearum to cucurbit plants.

2.
Chemistry ; 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33788327

RESUMO

Photoactive two-dimensional covalent organic frameworks (2D-COFs) have become promising heterogenous photocatalysts in visible-light-driven organic transformations recently. Herein, a visible-light-driven selective aerobic oxidation of various small organic molecules by using 2D-COFs as the photocatalyst was developed. In this protocol, due to the remarkable photocatalytic capability of hydrazone-based 2D-COF-1 on molecular oxygen activation, a wide range of amides, quinolones, heterocyclic compounds, and sulfoxides were delivered with high efficiency and excellent functional group tolerance under very mild reaction conditions. Furthermore, benefiting from the inherent advantage of heterogenous photocatalysis , prominent sustainability and easy photocatalyst recyclability, a drug molecule (modafinil) and an oxidized mustard gas simulant (2-chloroethyl ethyl sulfoxide) were selectively and easily obtained in scale-up reactions. Mechanistic investigations have been conducted using radical quenching experiments and in situ ESR spectroscopy, all corroborating the proposed role of 2D-COF-1 in photocatalytic cycle.

3.
Int J Occup Saf Ergon ; : 1-28, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33754949

RESUMO

Objective: This study aims to examine moisture distribution and transfer in firefighter protective clothing when the moisture from atmosphere and skin sweat were considered simultaneously.Methods: A self-developed test apparatus was used to simulate moisture transfer through the protective clothing under an exposure of thermal radiation. The weights of each-layer fabric before and after the heat exposure were measured for analyzing the moisture distribution and transfer.Results: The moisture levels in each-layer fabric before the exposure presented an increase over the initial moisture content. After the dry heat exposure, the moisture content in each-layer fabric reduced gradually. However, the existence of hot steam increased the moisture content stored in the fabric system and accelerated the moisture transmitting to the skin surface. In addition, the amount of outward water evaporation for the dry heat exposure was moderately more than inward water evaporation, while the amount of inward water evaporation was greatly more than outward water evaporation for the wet heat exposure.Conclusion: The moisture transfer in the firefighter protective clothing was two-way transmission during both heat exposures. The understanding of moisture transfer helps to provide proper guidance to improve the thermal protection of clothing and reduce steam burns.

4.
J Ethnopharmacol ; 271: 113893, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33524511

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Zuojin Pill (ZJP) is a classic prescription composed of Coptis chinensis and Tetradium ruticarpum (A.Juss.) T.G.Hartley, which is often used in the treatment of digestive system diseases. AIM OF THIS STUDY: The purpose of this study was to explore the therapeutic effect and potential mechanism of ZJP on chronic atrophic gastritis (CAG) induced by MNNG. MATERIALS AND METHODS: The GES-1 and rat model of CAG was established by MNNG. Detection of cell viability, morphological changes and proliferation of GES-1 by CCK-8 and high content screening (HCS) assay. G-17, IL-8 and TNF-α in rat serum were detected by ELISA kit. The expression of related mRNA and protein on TGF-ß1/PI3K/Akt signal axis were detected by RT-PCR and Western blot. RESULTS: The results showed that ZJP could significantly improve the GES-1 damage induced by MNNG and improve the gastric histomorphology of CAG rats. The intervention of ZJP could significantly reduce the content of G-17 and inflammatory factors IL-8, TNF- α, IL-6 and IL-1ß, inhibit the expression of TGF-ß1, PI3K and their downstream signals p-Akt, p-mTOR, P70S6K, and promote the expression level of PTEN, LC3-II and Beclin-1. CONCLUSION: ZJP has a good therapeutic effect on CAG induced by MNNG, which may be closely related to the inhibition of TGF-ß1/PI3K/Akt signal pathway.

5.
Prep Biochem Biotechnol ; : 1-11, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33439089

RESUMO

Crude glycerol, a by-product of biodiesel production, was employed as the carbon source to produce lipase using Pichia pastoris. Under identical fermentation conditions, cell growth and lipase activity were improved using crude glycerol instead of pure glycerol. The impacts of crude glycerol impurities (methyl ester, grease, glycerol, methanol, and metal ions Na+, Ca2+, and Fe3+) on lipase production were investigated. Impurities accelerated P. pastoris entering the stationary phase. Na+, Ca2+, and grease in waste crude glycerol were the main factors influencing higher lipase activity. Through response surface optimization of Ca2+, Na+, and grease concentrations, lipase activity reached 1437 U/mL (15,977 U/mg), which was 2.5 times that of the control. This study highlights the economical and highly efficient valorization of crude glycerol, demonstrating its possible utilization as a carbon source to produce lipase by P. pastoris without pretreatment.

6.
Sheng Wu Gong Cheng Xue Bao ; 37(1): 88-99, 2021 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-33501792

RESUMO

The formation of most proteins consists of two steps: the synthesis of precursor proteins and the synthesis of functional proteins. In these processes, propeptides play important roles in assisting protein folding or inhibiting its activity. As an important polypeptide chain coded by a gene sequence in lipase gene, propeptide usually functions as an intramolecular chaperone, assisting enzyme molecule folding. Meanwhile, some specific sites on propeptide such as glycosylated sites, have important effect on the activity, stability in extreme environment, methanol resistance and the substrate specificity of the lipase. Studying the mechanism of propeptide-mediated protein folding, as well as the influence of propeptide on lipases, will allow to regulate lipase by alternating the propeptide folding behavior and in turn pave new ways for protein engineering research.


Assuntos
Lipase , Dobramento de Proteína , Lipase/genética , Lipase/metabolismo , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Precursores de Proteínas , Especificidade por Substrato
7.
Virol J ; 17(1): 191, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33287849

RESUMO

BACKGROUND: Influenza virus remains a continuous and severe threat to public health worldwide, and its prevention and treatment have always been a major international issue. Because of its ability to evade immune surveillance through rapid antigenic drift and antigenic shift, broad-spectrum vaccines seem increasingly important. METHODS: A mAb named 3C12 from an immortalized hybrid cell was generated via immunizing mice with HA2 protein from A/chicken/Anhui/BRI99/2016 (AH/BRI99/16, H9N2) generated by prokaryotic expression. Then, its broad-spectrum activity was analyzed by WB and IFA. Next, the minimal linear epitope was identified via analyzing the reaction of a series of HA truncations with 3C12. Finally, the protective effects of 3C12 were evaluated in vitro and in vivo infection experiments. RESULTS: The mAb could react with the viruses of subtypes H1, H2, H5, H8, H9, H12, H13, H16, and HA protein of H18 in group 1, but failed to react with viruses in group 2. The minimal linear epitope targeted by the mAb was 433NAELLVL439 in full length of HA and localized in the C-helix region of HA2 (residue 95-101, HA2 numbering). What's more, the mAb 3C12 inhibited H1, H2, H5, H8, H9, H12, H13 and H16 virus-replication in vitro and also has shown effectiveness in preventing and treating disease in mice challenged with lethal dose of AH/BRI99/16 (H9N2) virus in vivo. These results suggested that the broadly reactive anti-HA stem mAb 3C12 exhibited prophylactic and therapeutic efficacy. CONCLUSIONS: Here, we have demonstrated that the linear epitope identified in this study could be a novel target for developing broad-spectrum influenza diagnostics or vaccine design, and the HA2-based monoclonal antibody is indeed a promising strategy for broad-spectrum protection against seasonal and pandemic influenza viruses.

8.
Eur Heart J ; 2020 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-33280021

RESUMO

AIMS: G protein-coupled receptor kinase 4 (GRK4) has been reported to play an important role in hypertension, but little is known about its role in cardiomyocytes and myocardial infarction (MI). The goal of present study is to explore the role of GRK4 in the pathogenesis and progression of MI. METHODS AND RESULTS: We studied the expression and distribution pattern of GRK4 in mouse heart after MI. GRK4 A486V transgenic mice, inducible cardiomyocyte-specific GRK4 knockout mice, were generated and subjected to MI with their control mice. Cardiac infarction, cardiac function, cardiomyocyte apoptosis, autophagic activity, and HDAC4 phosphorylation were assessed. The mRNA and protein levels of GRK4 in the heart were increased after MI. Transgenic mice with the overexpression of human GRK4 wild type (WT) or human GRK4 A486V variant had increased cardiac infarction, exaggerated cardiac dysfunction and remodelling. In contrast, the MI-induced cardiac dysfunction and remodelling were ameliorated in cardiomyocyte-specific GRK4 knockout mice. GRK4 overexpression in cardiomyocytes aggravated apoptosis, repressed autophagy, and decreased beclin-1 expression, which were partially rescued by the autophagy agonist rapamycin. MI also induced the nuclear translocation of GRK4, which inhibited autophagy by increasing HDAC4 phosphorylation and decreasing its binding to the beclin-1 promoter. HDAC4 S632A mutation partially restored the GRK4-induced inhibition of autophagy. MI caused greater impairment of cardiac function in patients carrying the GRK4 A486V variant than in WT carriers. CONCLUSION: GRK4 increases cardiomyocyte injury during MI by inhibiting autophagy and promoting cardiomyocyte apoptosis. These effects are mediated by the phosphorylation of HDAC4 and a decrease in beclin-1 expression.

9.
Hepatol Res ; 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33227168

RESUMO

AIM: The aim of this study was to use a metabonomics approach to identify potential biomarkers of exhaled breath condensate (EBC) for predicting the prognosis of acute-on-chronic liver failure (ACLF). METHODS: Using liquid chromatography mass spectrometry, EBC metabolites of ACLF patients surviving without liver transplantation (n=57) and those with worse outcomes (n=45), and controls (n=16) were profiled from a specialized liver disease center in Beijing. The metabolites were used to identify candidate biomarkers, and the predicted performance of potential biomarkers was tested. RESULTS: 41 metabolites, involving glycerophospholipid metabolism, sphingolipid metabolism, arachidonic acid metabolism and amino acid metabolism, as candidate biomarkers for discriminating the different outcomes of ACLF were selected. A prognostic model was constructed by a panel of four metabolites including phosphatidylinositol [20:4(5Z,8Z,11Z,14Z)/13:0], phosphatidyl ethanolamine (12:0/22:0), l-metanephrine and ethylbenzene, which could predict the worse prognosis in ACLF patients with sensitivity (84.4%) and specificity (89.5%) (area under the receiver operating characteristic curve [AUC] = 0.859, 95% confidence interval [CI] = 0.787-0.931). Compared with MELD score (AUC = 0.639, 95% CI = 0.526-0.753) and MELD-Na score (AUC = 0.692, 95% CI = 0.582-0.803), EBC-associated metabolite signature model could better predict worse outcomes in patients with ACLF (p<0.05). Using the MELD-Na score and EBC metabolite signatures, a decision tree model was built for predicting the prognosis of ACLF identified on logistic regression analyses (AUC = 0.906, 95% CI = 0.846-0.965). CONCLUSION: EBC metabolic signatures show promise as potential biomarkers for predicting worse prognosis of ACLF.

10.
Nat Commun ; 11(1): 5762, 2020 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-33188184

RESUMO

Occurrence of Colorectal cancer (CRC) is relevant with gut microbiota. However, role of IRF3, a key signaling mediator in innate immune sensing, has been barely investigated in CRC. Here, we unexpectedly found that the IRF3 deficient mice are hyper-susceptible to the development of intestinal tumor in AOM/DSS and Apcmin/+ models. Genetic ablation of IRF3 profoundly promotes the proliferation of intestinal epithelial cells via aberrantly activating Wnt signaling. Mechanically, IRF3 in resting state robustly associates with the active ß-catenin in the cytoplasm, thus preventing its nuclear translocation and cell proliferation, which can be relieved upon microbe-induced activation of IRF3. In accordance, the survival of CRC is clinically correlated with the expression level of IRF3. Therefore, our study identifies IRF3 as a negative regulator of the Wnt/ß-catenin pathway and a potential prognosis marker for Wnt-related tumorigenesis, and describes an intriguing link between gut microbiota and CRC via the IRF3-ß-catenin axis.


Assuntos
Carcinogênese/metabolismo , Carcinogênese/patologia , Núcleo Celular/metabolismo , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/prevenção & controle , Fator Regulador 3 de Interferon/metabolismo , beta Catenina/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Enterócitos/metabolismo , Enterócitos/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Antígeno Ki-67/metabolismo , Camundongos Endogâmicos C57BL , Ligação Proteica , Domínios Proteicos , Transporte Proteico , Análise de Sobrevida , Via de Sinalização Wnt , beta Catenina/química
11.
3 Biotech ; 10(12): 523, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33194527

RESUMO

Long-chain fatty acids are widely used in food and chemical industries, and the enzymatic preparation of fatty acids is considered an environmentally friendly process. In the present study, long-chain fatty acids were prepared by the enzymatic hydrolysis of rapeseed oil with a genetically engineered lipase. Because thermophilic lipase has strong stability at higher temperatures, it was more suitable for the industrial production of long-chain fatty acids. Therefore, the thermophilic lipase BTL2 from Geobacillus thermocatenulatus was efficiently expressed in E. coli BL21(DE3) cells with an enzyme activity of 39.50 U/mg followed by gene codon optimisation. Experimental results showed that the recombinant lipase BTL2 exhibited excellent resistance to certain organic solvents (n-hexane, benzene, ethanol, and butanol). The metal cation Ca2+ and the non-ionic surfactant Triton-100X enhanced enzyme activity by 7.36% and 56.21% respectively. Moreover, the acid value of the liberated long-chain fatty acids by hydrolysing rapeseed oil was approximately 161.64 mg KOH/g at 50 °C in 24 h, the hydrolytic conversion rate was 91.45%, and the productivity was approximately 6.735 mg KOH/g h. These results suggested that the recombinant lipase BTL2 has excellent hydrolytic performance for rapeseed oil and showed great potential for the enzymatic preparation of long-chain fatty acids.

12.
J Cell Sci ; 133(22)2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33172984

RESUMO

In most eukaryotes, the meiotic chromosomal bouquet (comprising clustered chromosome ends) provides an ordered chromosome arrangement that facilitates pairing and recombination between homologous chromosomes. In the protist Tetrahymena thermophila, the meiotic prophase nucleus stretches enormously, and chromosomes assume a bouquet-like arrangement in which telomeres and centromeres are attached to opposite poles of the nucleus. We have identified and characterized three meiosis-specific genes [meiotic nuclear elongation 1-3 (MELG1-3)] that control nuclear elongation, and centromere and telomere clustering. The Melg proteins interact with cytoskeletal and telomere-associated proteins, and probably repurpose them for reorganizing the meiotic prophase nucleus. A lack of sequence similarity between the Tetrahymena proteins responsible for telomere clustering and bouquet proteins of other organisms suggests that the Tetrahymena bouquet is analogous, rather than homologous, to the conserved eukaryotic bouquet. We also report that centromere clustering is more important than telomere clustering for homologous pairing. Therefore, we speculate that centromere clustering may have been the primordial mechanism for chromosome pairing in early eukaryotes.

13.
Transl Pediatr ; 9(5): 695-701, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33209733

RESUMO

Aortic complications of Loeys-Dietz syndrome (LDS) rarely present in children. Here we describe a case of LDS type 2 in a 3-year-old child with severe aortic root dilation and severe aortic regurgitation. A Bentall procedure combined with a Cabrol-type coronary modification was used to treat this child. In order to minimize the need for reintervention as the child grows. We chose a composite valve-graft by a St Jude Regent 21# mechanical valve seated within a 24 mm Gore-Tex graft to finish the Bentall procedure. Echocardiographic studies demonstrated good valve and ventricular function at 1-year follow-up. This child is one of the youngest LDS patients to receive a Bentall procedure and the way using a composite valve-graft to finish the operation can provide a reference for the surgical strategies of such patients in the future. Children with LDS and severe aortic annulus dilatation combined with severe aortic valve regurgitation require early surgical intervention, and implantation of a mechanical valved-conduit can be utilized successfully. Life-long follow-up of the valved-conduit and arterial vessels of these patients is necessary. The experience gained from this case contributes to the management of the rare LDS patient who presents at an early age with aortic root and valve pathology. Close monitoring and early intervention are important.

14.
Artigo em Inglês | MEDLINE | ID: mdl-33184764

RESUMO

Biodiesel biosynthesis with enzymatic transesterification is considered green, sustainable, and environmentally friendly method. Lipase from Burkholderia cepacia G63 has excellent catalytic properties in biodiesel production. Lipase chaperones promote secretion and folding of enzymes, thereby enhancing enzymatic activity. In the current study, heterologous co-expression of lipase (lipA) and chaperone (lipB) was achieved in Escherichia coli through codon optimization. The enzymatic activity of purified and renatured lipAB was 2080.23 ± 19.18 U/g at 50 °C and pH 8.0. Moreover, lipAB showed increased resistance to pH and temperature changes, and lipAB retained stable catalytic properties after treatment with metal ions, organic solvents, and surfactants, namely Mg2+, methanol, and Triton-100X. Besides, using recombinant lipase lipAB as catalysts, biodiesel was synthesized using rapeseed oil under 50 °C for 72 h with a yield of 90.23%. Thus, the current study confirmed that co-expression of lipase and its chaperone is an effective strategy to enhance enzyme activity and improve the biochemical profile, meanwhile, showing that lipAB is a promising biocatalyst for biodiesel production.

16.
Front Immunol ; 11: 1801, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33013831

RESUMO

A recently developed humanized mouse has been used to assess the immune response evoked against the isolated attenuated C9 parasite clone (C9-M; carrying a single insertion disrupting the open reading frame (ORF) of PF3D7_1305500) of Plasmodium falciparum. Significant human RBC engraftment was achieved by ameliorating the residual non-adaptive immune response using clodronate-loaded liposome treatment. Controlled reactive professional phagocytic leukocytes in immunodeficient mice allowed for sizeable human blood chimerism and injected huRBCs acted as bona fide host cells for P. falciparum. huRBC-reconstituted immunodeficient mice received infectious challenge with attenuated P. falciparum C9 parasite mutants (C9-M), complemented (C9-C), and wild type (NF54) progenitors to study the role of immune effectors in the clearance of the parasite from mouse circulation. C9-M and NF54 parasites grew and developed in the huRBC-reconstituted humanized NSG mice. Further, the presence of mutant parasites in deep-seated tissues suggests the escape of parasites from the host's immune responses and thus extended the survival of the parasite. Our results suggest an evasion mechanism that may have been employed by the parasite to survive the mouse's residual non-adaptive immune responses. Collectively, our data suggest that huRBCs reconstituted NSG mice infected with attenuated P. falciparum is a valuable tool to explore the role of C9 mutation in the growth and survival of parasite mutants and their response to the host's immune responses. This mouse might help in identifying novel chemotherapeutic targets to develop new anti-malarial drugs.

17.
Genomics ; 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33049361

RESUMO

Influenza A virus is a single-stranded RNA virus that can cause great mortality and economic loss worldwide. Circular RNAs (circRNAs) are non-coding RNAs that have been shown to have important functions in the regulation of biological processes. However, their functions during the influenza A virus infection process remain unclear. Herein, RNA sequencing technology was used to identify circRNAs expressed in mouse lungs during infection with H7N9/PB2-627 K/701D (H7N9/Wild-type) virus and PB2 mutant viruses (H7N9/PB2-627E/701D and H7N9/PB2-627E/701 N). We identified 7126 circRNAs at different genomic locations during H7N9 influenza virus and its mutant virus infections, of which 186 were differentially expressed. Enrichment analysis revealed that the differentially expressed circRNAs were associated with the viral infection process. Our study shows that circRNA expression profiles were altered following H7N9 influenza A virus infection and the differentially expressed circRNAs may have an important immune-regulating function during viral infection.

18.
Membranes (Basel) ; 10(9)2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32872637

RESUMO

Polyoxometalates (POMs) has proved its advantage in constructing high-performance nanocomposite membranes such as catalytic membranes, adsorptive membranes, and forward osmosis membranes. However, it is challenging or tedious to characterize its distribution and effect on the membrane structures due to the equipment resolution limitation, discrete nano-scaled structures of POMs, and limited doping amount compared to the polymeric membrane matrix. In this paper, POMs-functionalized polyvinylidene fluoride (PVDF) membranes were fabricated by phase inversion combined with the sol-gel method, and electrochemical impedance spectroscopy (EIS) was utilized to analyze the nanocomposite membrane intrinsic properties. Through adjusting the additives in the sol-forming process, a set of membranes with varied intrinsic properties were developed accordingly. The wetting degree of the membranes related to the hydrophilic nature of the membrane surfaces had a crucial influence on the impedance measurements at the early stage. Through EIS analysis, it was demonstrated that the amination of the membrane matrix through (3-aminopropyl)trimethoxysilane (APTMS) treatment and the immobilization of POMs through electrostatic attraction would not generate new pore structures into the membrane and only alter the membrane surface roughness and composition. To my knowledge, it is the first time that EIS was utilized to characterize the hydrophilicity of the membranes and pore structures of the POMs-modified membranes. Our findings indicate that EIS can provide valuable information for probing the structures of other nano-materials-incorporated membranes.

19.
Insect Sci ; 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32935926

RESUMO

Wing polymorphism significantly contributes to the ecological success of some insect species. For example, the brown planthopper (BPH) Nilaparvata lugens, which is one of the most destructive rice pests in Asia, can develop into either highly mobile long-winged or highly fecund short-winged adult morphs. A recent study reported a highly provocative result that the Hox gene Ultrabithorax (Ubx) is expressed in BPH forewings and showed that this wing development gene is differentially expressed in nymphs that develop into long-winged versus short-winged morphs. Here, we found that Ubx may be a mir-9a target, and used dual luciferase reporter assays and injected micro RNA (miRNA) mimics and inhibitors to confirm the interactions between mir-9a and NlUbx. We measured the mir-9a and NlUbx expression profiles in nymphs and found that the expression of these two biomolecules was negatively correlated. By rearing BPH nymphs on host rice plants with different nutritional status, we were able to characterize a regulatory cascade between insulin receptor genes, mir-9a, and NlUbx that regulate wing length in BPHs. When host quality was low, NlInR1 expression in the nymph terga increased and NlInR2 expression decreased; this led to a higher mir-9a level, which in turn reduced the NlUbx transcript level and ultimately resulted in longer wing lengths. Beyond extending our understanding of the interplay between host plant status and genetic events that modulate polymorphism, we demonstrated both the upstream signal and miRNA-based regulatory mechanism that control Ubx expression in BPH forewings.

20.
Materials (Basel) ; 13(16)2020 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-32823632

RESUMO

The application of fire-retardant fabrics is essential for providing thermal protective function of the garments. Appropriate clothing design are beneficial for preventing the wearers from skin burn injuries and heat strains simultaneously. The intention of this work was to investigate the effects of clothing ventilation designs on its thermal protective performance by bench-scale tests. Four boundary conditions were designed to simulate the garment aperture structures on fabric level. Tests of thermal shrinkage, mass loss and time-to-second-degree-burns were performed with and without air gap under three heat-flux levels for two kinds of inherently fire-retardant fabrics. The impacts of fabric type, heat-flux level, air gap and boundary condition were analyzed. The presence of a 6.4-mm air gap could improve thermal protective performance of the fabrics, however, the garment openings would decrease this positive effects. More severe thermal aging found for spaced test configuration indicated the importance of balancing the service life and thermal protective performance of the clothing. The findings of this study implied that the characteristics of fabric type, air gap, boundary condition, and their effects on fabric thermal aging should be considered during clothing ventilation designs, to balance the thermal protection and comfort of the protective gear.

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