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1.
BMC Genomics ; 22(Suppl 3): 793, 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34736408

RESUMO

BACKGROUND: Winter wheat requires prolonged exposure to low temperature to initiate flowering (vernalization). Shoot apical meristem of the crown is the site of cold perception, which produces leaf primordia during vegetative growth before developing into floral primordia at the initiation of the reproductive phase. Although many essential genes for winter wheat cold acclimation and floral initiation have been revealed, the importance of microRNA (miRNA) meditated post-transcriptional regulation in crowns is not well understood. To understand the potential roles of miRNAs in crown tissues, we performed a temporal expression study of miRNAs in crown tissues at the three-leaf stage, winter dormancy stage, spring green-up stage, and jointing stage of winter wheat grown under natural growth conditions. RESULTS: In total, 348 miRNAs belonging to 298 miRNA families, were identified in wheat crown tissues. Among them, 92 differentially expressed miRNAs (DEMs) were found to be significantly regulated from the three-leaf stage to the jointing stage. Most of these DEMs were highly expressed at the three-leaf stage and winter dormancy stage, and then declined in later stages. Six DEMs, including miR156a-5p were markedly induced during the winter dormancy stage. Eleven DEMs, including miR159a.1, miR390a-5p, miR393-5p, miR160a-5p, and miR1436, were highly expressed at the green-up stage. Twelve DEMs, such as miR172a-5p, miR394a, miR319b-3p, and miR9676-5p were highly induced at the jointing stage. Moreover, 14 novel target genes of nine wheat or Pooideae-specific miRNAs were verified using RLM-5' RACE assay. Notably, six mTERFs and two Rf1 genes, which are associated with mitochondrial gene expression, were confirmed as targets of three wheat-specific miRNAs. CONCLUSIONS: The present study not only confirmed the known miRNAs associated with phase transition and floral development, but also identified a number of wheat or Pooideae-specific miRNAs critical for winter wheat cold acclimation and floral development. Most importantly, this study provided experimental evidence that miRNA could regulate mitochondrial gene expression by targeting mTERF and Rf1 genes. Our study provides valuable information for further exploration of the mechanism of miRNA mediated post-transcriptional regulation during winter wheat vernalization and inflorescent initiation.


Assuntos
MicroRNAs , Triticum , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Humanos , Meristema , MicroRNAs/genética , Triticum/genética
2.
Adv Mater ; : e2105951, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34617348

RESUMO

Zn metal anode has garnered growing scientific and industrial interest owing to its appropriate redox potential, low cost, and high safety. Nevertheless, the instability of Zn anode caused by dendrite formation, hydrogen evolution, and side reactions has greatly hampered its commercialization. Herein, an in situ grown ZnSe overlayer is crafted over one side of commercial Zn foil via chemical vapor deposition in a scalable manner, aiming to achieve optimized electrolyte/Zn interfaces with large-scale viability. Impressively, thus-derived ZnSe coating functions as a cultivator to guide oriented growth of Zn (002) plane at the infancy stage of stripping/plating cycles, thereby inhibiting the formation of Zn dendrites and the occurrence of side reactions. As a result, high cyclic stability (1530 h at 1.0 mA cm-2 /1.0 mAh cm-2 ; 172 h at 30.0 mA cm-2 /10.0 mAh cm-2 ) in symmetric cells is harvested. Meanwhile, when paired with V2 O5 based cathode, assembled full cell achieves an outstanding capacity (194.5 mAh g-1 ) and elongated lifespan (a capacity retention of 84% after 1000 cycles) at 5.0 A g-1 . The reversible Zn anode enabled by the interfacial manipulation strategy via ZnSe cultivator is anticipated to satisfy the demand of commercial use.

3.
Pediatr Pulmonol ; 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34672436

RESUMO

BACKGROUND: With the onset of the coronavirus disease 2019 (COVID-19) pandemic, many experts expected that asthma-associated morbidity because of severe acute respiratory syndrome coronavirus 2 infection would dramatically increase. However, some studies suggested that there was no apparent increasing in asthma-related morbidity in children with asthma, it is even possible children may have improved outcomes. To understand the relationship between the COVID-19 pandemic and asthma outcomes, we performed this article. METHODS: We searched PubMed, Embase, and Cochrane Library to find literature from December 2019 to June 2021 related to COVID-19 and children's asthma control, among which results such as abstracts, comments, letters, reviews, and case reports were excluded. The level of asthma control during the COVID-19 pandemic was synthesized and discussed by outcomes of asthma exacerbation, emergency room visit, asthma admission, and childhood asthma control test (c-ACT). RESULTS: A total of 22,159 subjects were included in 10 studies. Random effect model was used to account for the data. Compared with the same period before the COVID-19 pandemic, asthma exacerbation reduced (odds ratio [OR] = 0.26, 95% confidence interval [CI] = [0.14-0.48], Z = 4.32, p < 0.0001), the odds of emergency room visit decreased as well (OR = 0.11, 95% CI = [0.04-0.26], Z = 4.98, p < 0.00001). The outcome of asthma admission showed no significant difference (OR = 0.84, 95% CI = [0.32-2.20], Z = 0.36, p = 0.72). The outcome of c-ACT scores were not analyzed because of the different manifestations used. Overall, c-ACT scores reduced during the pandemic. CONCLUSION: Compared to the same period before the COVID-19 pandemic, the level of asthma control has been significantly improved. We need to understand the exact factors leading to these improvements and find methods to sustain it.

4.
Adv Mater ; 33(43): e2103050, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34463382

RESUMO

Lithium-sulfur (Li-S) batteries are promising candidates for next-generation energy storage, yet they are plagued by the notorious polysulfide shuttle effect and sluggish redox kinetics. While rationally designed redox mediators can facilitate polysulfide conversion, favorable bidirectional sulfur electrocatalysis remains a formidable challenge. Herein, selective dual-defect engineering (i.e., introducing both N-doping and Se-vacancies) of a common MoSe2 electrocatalyst is used to manipulate the bidirectional Li2 S redox. Systematic theoretical prediction and detailed electrokinetic analysis reveal the selective electrocatalytic effect of the two types of defects, thereby achieving a deeper mechanistic understanding of the bidirectional sulfur electrochemistry. The Li-S battery using this electrocatalyst exhibits excellent cyclability, with a low capacity decay rate of 0.04% per cycle over 1000 cycles at 2.0 C. More impressively, the potential for practical applications is highlighted by a high areal capacity (7.3 mAh cm-2 ) and the construction of a flexible pouch cell. Such selective electrocatalysis created by dual-defect engineering is an appealing approach toward working Li-S systems.

5.
ACS Nano ; 15(9): 14105-14115, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34351143

RESUMO

Although lithium-sulfur (Li-S) batteries have long been touted as next-generation energy storage devices, the rampant dendrite growth at the anode side and sluggish redox kinetics at the cathode side drastically impede their practical application. Herein, a dual-functional fibrous skeleton implanted with single-atom Co-Nx dispersion is devised as an advanced modificator to realize concurrent regulation of both electrodes. The rational integration of single-atomic Co-Nx sites could convert the fibrous carbon skeleton from lithiophobic to lithiophilic, helping assuage the dendritic formation for the Li anode. Meanwhile, the favorable electrocatalytic activity from the Co-Nx species affording a lightweight feature effectively enables expedited bidirectional conversion kinetics of sulfur electrochemistry, thereby inhibiting the polysulfide shuttle. Moreover, the interconnected porous framework endows the entire skeleton with good mechanical robustness and fast electron/ion transportation. Benefiting from the synergistic effects between atomically dispersed Co-Nx sites and three-dimensional conductive networks, the integrated Li-S full batteries can achieve a reversible areal capacity (>7.0 mAh cm-2) at a sulfur loading of 6.9 mg cm-2. This work might be beneficial to the development of practically viable Li-S batteries harnessing single-atom mediators.

6.
Angew Chem Int Ed Engl ; 60(46): 24558-24565, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34435420

RESUMO

Witnessing compositional evolution and identifying the catalytically active moiety of electrocatalysts is of paramount importance in Li-S chemistry. Nevertheless, this field remains elusive. We report the scalable salt-templated synthesis of Se-vacancy-incorporated MoSe2 architecture (SeVs-MoSe2 ) and reveal the phase evolution of the defective precatalyst in working Li-S batteries. The interaction between lithium polysulfides and SeVs-MoSe2 is probed to induce the transformation from SeVs-MoSe2 to MoSeS. Furthermore, operando Raman spectroscopy and ex situ X-ray diffraction measurements in combination with theoretical simulations verify that the effectual MoSeS catalyst could help promote conversion of Li2 S2 to Li2 S, thereby boosting the capacity performance. The Li-S battery accordingly exhibits a satisfactory rate and cycling capability even with and elevated sulfur loading and lean electrolyte conditions (7.67 mg cm-2 ; 4.0 µL mg-1 S ). This work elucidates the design strategies and catalytic mechanisms of efficient electrocatalysts bearing defects.

7.
J Control Release ; 337: 236-247, 2021 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-34273419

RESUMO

Internal and external factors cause various types of wounds on the skin. Infections, nonhealing chronic wounds, and aesthetic and functional recovery all cause challenges for clinicians. The development of nanotechnology in biomedicine has brought many new materials, methods and therapeutic targets for the treatment of wounds, which are believed to have great prospects. In this work, the nanomaterials applied in different stages to promote wound healing and systematically expounded their mechanisms were reviewed. Then, the difficulties and defects of the present research and suggested methods for improvement were pointed out. Moreover, based on the current application status of nanomaterials in wound treatment, some new ideas for subsequent studies were proposed and the feasibility of intelligent healing by real-time monitoring, precision regulation, and signal transmission between electronic signals and human nerve signals in the future were discussed. This review will provide valuable directions and spark new thoughts for researchers.


Assuntos
Materiais Biocompatíveis , Nanoestruturas , Humanos , Nanotecnologia , Pele , Cicatrização
8.
Nanomicro Lett ; 13(1): 104, 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-34138362

RESUMO

SeS2 has become a promising cathode material owing to its enhanced electrical conductivity over sulfur and higher theoretical specific capacity than selenium; however, the working Li-SeS2 batteries have to face the practical challenges from the severe shuttling of soluble dual intermediates of polysulfide and polyselenide, especially in high-SeS2-loading cathodes. Herein, a natural organic polymer, Nicandra physaloides pectin (NPP), is proposed to serve as an effective polysulfide/polyselenide captor to address the shuttling issues. Informed by theoretical calculations, NPP is competent to provide a Lewis base-based strong binding interaction with polysulfides/polyselenides via forming lithium bonds, and it can be homogeneously deposited onto a three-dimensional double-carbon conductive scaffold to finally constitute a polysulfide/polyselenide-immobilizing interlayer. Operando spectroscopy analysis validates the enhanced polysulfide/polyselenide trapping and high conversion efficiency on the constructed interlayer, hence bestowing the Li-SeS2 cells with ultrahigh rate capability (448 mAh g-1 at 10 A g-1), durable cycling lifespan (≈ 0.037% capacity attenuation rate per cycle), and high areal capacity (> 6.5 mAh cm-2) at high SeS2 loading of 15.4 mg cm-2. Importantly, pouch cells assembled with this interlayer exhibit excellent flexibility, decent rate capability with relatively low electrolyte-to-capacity ratio, and stable cycling life even under a low electrolyte condition, promising a low-cost, viable design protocol toward practical Li-SeS2 batteries.

9.
Environ Res ; 200: 111463, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34111436

RESUMO

The Chinese government has developed an ambitious project to promote the application of ethanol gasoline (E10) on a national scale since 2017. Given the difference in fuel properties between E10 and traditional gasoline, it is necessary to evaluate the volatile organic compound (VOC) emissions from E10-fuelled vehicles. In this study, a two-week sampling campaign was conducted in an urban tunnel, in which E10-fuelled vehicles were dominant, to evaluate the characteristics of VOC emissions from the mixed fleet. In total, 105 VOC species were identified, and the ozone formation potential (OFP) and secondary organic aerosol formation potential (SOAFP) were estimated. The results showed that for vehicular VOC concentrations in the tunnel, alkanes, oxygenated VOCs (OVOCs) and alkenes were the most abundant VOC groups, with the average proportion being more than 80% of the total VOCs. The fleet-average VOC emission factor (EF) was 14.8 mg/km/veh, which was much lower than that from traditional gasoline-fuelled vehicle fleets, and alkanes, OVOCs, alkenes and aromatics were the major VOC groups. Because of the large number of E10-fuelled vehicles in the mixed fleet, a high proportion of OVOCs among the vehicular VOC emissions was observed. Ethane, acrolein, ethanol, ethylene and toluene were the top five VOC species with the largest EF in VOC emissions from the fleet. Alkenes were the main contributors with an average contribution of 43.9% of the total OFP, whereas aromatics dominated the total SOAFP by 95.8% on average. These results may provide a reference for the extensive application of ethanol gasoline and the development of vehicular emission models.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Aerossóis/análise , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental , Ozônio/análise , Emissões de Veículos/análise , Compostos Orgânicos Voláteis/análise
10.
BMC Infect Dis ; 21(1): 484, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34039307

RESUMO

BACKGROUND: Chromobacterium violaceum (C. violaceum) is a Gram-negative saprophytic bacterium that is widespread in tropical and subtropical environments, and belongs to conditional pathogenic bacteria. Human infection with C. violaceum is rare, and this can be fatal when the diagnosis and treatment are delayed, especially recurrent infection patients. Since clinicians lack the knowledge for C. violaceum, rapid diagnosis and early appropriate antimicrobial treatment remains challenging. CASE PRESENTATION: A 15-year-old male student was hospitalized for dark abscess, pustules, severe pain in both legs, and fever for 11 days. There were pustules with gray-white pus and red infiltrating plaques on the back, and the subcutaneous nodules could be touched in front of both tibias, with scab, rupture and necrotic tissue of the lower limb. The patient's condition rapidly progressed. Therefore, next-generation sequencing (NGS), pustular secretion and blood culture were concurrently performed. The final diagnosis for this patient was C. violaceum infection by NGS. However, no bacterial or fungal growth was observed in the pustular secretion and blood culture. After 4 weeks of treatment, the patient was discharged from the hospital without any complications associated with C. violaceum infection. CONCLUSION: Rapid diagnosis and early appropriate antimicrobial treatment is the key to the successful treatment of C. violaceum infection, especially in patients with sepsis symptoms. This case highlights that NGS is a promising tool for the rapid diagnosis of C. violaceum infection, preventing the delayed diagnosis and misdiagnosis of C. violaceum infection in patients who tested negative for pustular secretion and blood culture.


Assuntos
Antibacterianos/uso terapêutico , Chromobacterium/isolamento & purificação , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Adolescente , Chromobacterium/efeitos dos fármacos , Chromobacterium/genética , Diagnóstico Precoce , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/patologia , Humanos , Masculino , Reinfecção , Resultado do Tratamento
11.
Environ Sci Pollut Res Int ; 28(34): 47227-47238, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33893578

RESUMO

Vehicular emissions have become a primary anthropogenic source of urban atmospheric volatile halogenated hydrocarbons (VHCs) with the rapid increase of vehicle population, while characteristics of the VHC emissions from different vehicles were rarely systematically investigated. In this study, the on-road tailpipe emissions were sampled from seven in-use vehicles, including two light-duty gasoline vehicles (LDGV), three light-duty diesel trucks (LDDT), one heavy-duty diesel truck (HDDT), and a liquefied petroleum gas-electric hybrid bus (LPGB), using a portable emission measurement system (PEMS) combined with summa canisters, and 35 individual VHC species were identified by a gas chromatography mass spectrometry detector (GC-MSD). Results showed that VHC emissions under urban driving conditions were much higher than those on the suburban roads and highways. The VHC emission factors of LDGV were 1.2 ± 0.34 mg/km and 3.6 ± 1.5, 6.8 ± 0.89, and 1.6 ± 0.28 mg/km for LDDT, HDDT, and LPGB, respectively. For the LDGV, chlorobenzene, 1,2-dichloroethane, and hexachlorobutadiene were the top three VHC species. 1,2-Dichloroethane, trichloromethane, and methyl chloride were the main VHC constituents in the LDDT. Chlorobenzene was the most abundant VOC species for the HDDT, followed by 1,2-dichloroethane and 1,4-dichlorobenzene. The major species for LPGB were 1,2,4-trichlorobenzene, carbon tetrachloride, and benzyl chloride. The major tailpipe VHC species obtained in this study were partial consistent with previous studies with different test methods. The results provide an initial evaluation of the tailpipe VHC emissions, which may provide experimental data support for the refined source apportionment of atmospheric VHCs and the control of vehicular VHCs.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Halogenados , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Gasolina/análise , Veículos Automotores , Emissões de Veículos/análise
12.
ACS Nano ; 15(4): 7821-7832, 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33834770

RESUMO

MXenes are an emerging class of highly conductive two-dimensional (2D) materials with electrochemical storage features. Oriented macroscopic Ti3C2Tx fibers can be fabricated from a colloidal 2D nematic phase dispersion. The layered conductive Ti3C2Tx fibers are ideal candidates for constructing high-speed ionic transport channels to enhance the electrochemical capacitive charge storage performance. In this work, we assemble Ti3C2Tx fibers with a high degree of flake orientation by a wet spinning process with controlled spinning speeds and morphology of the spinneret. In addition to the effects of cross-linking of magnesium ions between Ti3C2Tx flakes, the electronic conductivity and mechanical strength of the as-prepared fibers have been improved to 7200 S cm-1 and 118 MPa, respectively. The oriented Ti3C2Tx fibers present a volumetric capacitive charge storage capability of up to 1360 F cm-3 even in a Mg-ion based neutral electrolyte, with contributions from both nanofluidic ion transport and Mg-ion intercalation pseudocapacitance. The oriented 2D Ti3C2Tx driven nanofluidic channels with great electronic conductivity and mechanical strength endows the MXene fibers with attributes for serving as conductive ionic cables and active materials for fiber-type capacitive electrochemical energy storage, biosensors, and potentially biocompatible fibrillar tissues.

13.
Small ; 17(18): e2005573, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33734605

RESUMO

Layered transition metal dichalcogenides (TMDs) of group VIB have been widely used in the realms of energy storage and conversions. Along with the existence of semiconducting states, their metallic phases have recently attracted numerous attentions owing to their fascinating physical and chemical properties. Many efforts have been devoted to obtain metallic TMDs with high purity and yield. Nevertheless, such metallic phase is thermodynamically metastable and tends to convert into semiconducting phase, which necessitates the exploration over effective strategies to ensure the stability. In this review, typical fabrication routes are introduced and those critical factors during preparation are elaborately discussed. Moreover, the stabilized strategies are summarized with concrete examples highlighting the key mechanisms toward efficient stabilization. Finally, emerging energy applications are overviewed. This review presents comprehensive research status of metallic group VIB TMDs, aiming to facilitate further scientific investigations and promote future practical applications in the fields of energy storage and conversion.

14.
Front Plant Sci ; 12: 643213, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33719323

RESUMO

Mepiquat chloride (MC) is the most important plant growth retardant that is widely used in cotton (Gossypium hirsutum L.) production to suppress excessive vegetative growth and improve plant architecture. MicroRNAs (miRNAs) are important gene expression regulators that control plant growth and development. However, miRNA-mediated post-transcriptional regulation in MC-induced growth inhibition remains unclear. In this study, the dynamic expression profiles of miRNAs responsive to MC in cotton internodes were investigated. A total of 508 known miRNAs belonging to 197 families and five novel miRNAs were identified. Among them, 104 miRNAs were differentially expressed at 48, 72, or 96 h post MC treatment compared with the control (0 h); majority of them were highly conserved miRNAs. The number of differentially expressed miRNAs increased with time after treatment. The expression of 14 known miRNAs was continuously suppressed, whereas 12 known miRNAs and one novel miRNA were continuously induced by MC. The expression patterns of the nine differentially expressed miRNAs were verified using qRT-PCR. The targets of the known and novel miRNAs were predicted. Four conserved and six novel targets were validated using the RLM-5' RACE assay. This study revealed that miRNAs play crucial regulatory roles in the MC-induced inhibition of internode elongation. It can improve our understanding of post-transcriptional gene regulation in MC-mediated growth inhibition and could potentially facilitate the breeding of dwarf cotton.

15.
J Dermatol ; 48(4): 519-528, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33458872

RESUMO

PSTPIP1-associated myeloid-related proteinaemia inflammatory (PAMI) syndrome has been described as a rare and distinct clinical phenotype of PSTPIP1-associated inflammatory diseases. We report PSTPIP1 mutation in both father and son who have leukopenia and acne-like lesions. Through whole-exome sequencing on blood DNA, it is found a heterozygous mutation of PSTPIP1 gene c.748G>A on the father and son. The diagnosis of PAMI is made based on DNA sequencing results and clinical characteristics of typical lesions, leukopenia, and the markedly increased serum S100A8/A9 (calprotectin).


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas do Citoesqueleto/genética , Pai , Humanos , Inflamação/genética , Masculino , Erros Inatos do Metabolismo dos Metais/genética , Mutação , Mutação de Sentido Incorreto , Síndrome
16.
Open Forum Infect Dis ; 8(1): ofaa562, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33447633

RESUMO

Background: High-quality evidence confirms that the clinical efficacy of peramivir in severe influenza patients with primary viral pneumonia is lacking. To optimize clinical medication, we evaluate the different efficacy between peramivir and oseltamivir in the treatment of severe influenza A with primary viral pneumonia. Methods: A single-center, randomized, controlled trial was conducted during the Chinese influenza season from December 2018 to April 2019 in patients with severe influenza A with primary viral pneumonia. A total of 40 inpatients were enrolled and treated with either intravenous peramivir (300 mg, once daily for 5 days) or oral oseltamivir (75 mg, twice daily for 5 days). Results: The duration of influenza virus nucleic acid positivity in the oseltamivir group and the peramivir group was 2.95 days and 2.80 days, respectively. The remission times of clinical symptoms in the oseltamivir group and the peramivir group were 3.90 days and 3.25 days, respectively. In addition, the remission time of cough symptoms in the peramivir group (63.89 hours) was shorter than that in the oseltamivir group (75.53 hours). There was no significant difference between these values (P > .05). The remission time of fever symptoms in the oseltamivir group was 23.67 hours, which was significantly longer than that in the peramivir group (12.32 hours) (P = .034). Conclusions: Peramivir is no less effective than oseltamivir in the treatment of severe influenza A with primary viral pneumonia, and patients treated with peramivir had significantly shorter remission times of fever symptoms than those treated with oseltamivir.

17.
J Hazard Mater ; 410: 124566, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33323305

RESUMO

BACKGROUND: This study aimed to evaluate the safety of applying zinc oxide nanoparticles (ZnO NPs) to pathological skin. The majority of previous studies confirmed the safety of applying ZnO NPs to normal skin. However, we know very little about the risks of using sunscreen, cosmetics and topical drugs containing ZnO NPs for individuals with skin diseases. RESULTS: ZnO NPs passed through gaps between keratinocytes and entered stratum basale of epidermis and dermis in imiquimod-induced psoriasis-like skin lesions. Application of a ZnO NP-containing suspension for 3 connective days delayed the healing of the epidermal barrier; increased the expression levels of inflammatory cytokines; promoted keratinocyte apoptosis and disturbed redox homeostasis. In TNF-α-stimulated HaCaT cells, QNZ and JSH-23 (NFκB inhibitors) blocked ZnO NP-induced inflammation. JSH-23 and NAC (a precursor of cysteine) inhibited ZnO NP-induced nuclear translocation of p-NFκB p65, cysteine deficiency and apoptosis. Additionally, ZnO NPs decreased CD98 level in main pathway and failed to activate transsulfuration pathway in cysteine biosynthesis. CONCLUSIONS: ZnO NPs can enter psoriasis-like skin lesions and promote inflammation and keratinocyte apoptosis through nuclear translocation of p-NFκB p65 and cysteine deficiency. This work reminds the public that ZnO NPs have harmful effects on the recovery of inflammatory skin diseases.


Assuntos
Nanopartículas , Psoríase , Dermatopatias , Óxido de Zinco , Cisteína , Humanos , Queratinócitos , Psoríase/induzido quimicamente , Psoríase/tratamento farmacológico , Óxido de Zinco/toxicidade
18.
Bioresour Technol ; 319: 124132, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32971333

RESUMO

Corncob-based activated carbon has very good adsorption performance and can provide a favourable growing environment for microorganisms. In this study, a biofilter packed with corncob-based activated carbon was constructed to remove grease and total volatile organic compounds (TVOCs) in kitchen exhaust fume. Results show that the biofilter was suitable for the biodegradation of grease and VOCs, and the maximum elimination capacities (ECmax) were 112 and 235 g/(m3·h) at an empty bed residence time of 3.24 s, respectively. When the pH of the filler dropped to 5.0 ± 0.2, the removal efficiencies (RE) of grease and TVOCs in the biofilter decreased to the minimum values (75% and 77%, respectively). The REmax were respectively 88 ± 4% (for TVOC) at 70% filler moisture content and 90 ± 3% (for grease) at 76% filler moisture content. Molecular characterization results showed Thermobacillus sp. as dominating microbial group in the packing media.


Assuntos
Microbiota , Compostos Orgânicos Voláteis , Biodegradação Ambiental , Carvão Vegetal , Filtração
19.
Artigo em Inglês | MEDLINE | ID: mdl-33312222

RESUMO

Objective: To carry out the meta-analysis on the clinical safety of glycyrrhizic acid and the influencing factors between 18α-glycyrrhizinate (18α-GL) and 18ß-glycyrrhizinate (18ß-GL). Methods: Magnesium isoglycyrrhizinate injection was used as the representative preparation of 18α-GL, and compound glycyrrhizin injection was used as the representative preparation of 18ß-GL. The clinical control trial of magnesium isoglycyrrhizinate injection and compound glycyrrhizin injection was searched in a computer, which was published from January 2006 to December 2019 on the databases such as PubMed, China National Knowledge Infrastructure (CNKI), China Science and Technology Journal Database (CSTJ), and Wanfang Medical Network (Wanfang Data). The data associated with adverse drug reactions (ADRs) were extracted. RevMan5.3 was used for statistical analysis. Results: Finally, 24 studies were included, and 2757 patients were involved, of which the experimental group was mainly treated with magnesium isoglycyrrhizinate, while the control group was mainly treated with compound glycyrrhizin. The results showed that the occurrence of ADRs was significantly lower in the experimental group than that in the control group, and the difference between two groups was statistically significant (RR = 0.26, 95% CI = (0.18, 0.38), P < 0.00001). There was no heterogeneity among the studies (I 2 = 0%, P=1.00). Conclusion: Compared with 18ß-GL, 18α-GL had a lower incidence of adverse reactions and better clinical safety.

20.
ACS Nano ; 14(11): 16073-16084, 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33156985

RESUMO

The Li-S battery has emerged as a promising next-generation system for advanced energy storage. Notwithstanding the recent progress, the problematic polysulfide shuttling, retarded sulfur redox, and low output of volumetric capacity remain daunting challenges toward its practicability. In response, this work demonstrates herein a universal approach to in situ craft MOx-MXene (M: Ti, V, and Nb) heterostructures as heavy and multifunctional hosts to harvest good battery performances with synchronous polysulfide immobilization and conversion. Theoretical calculations indicate that the in situ implanted oxides boost the reaction kinetics of polysulfide transformation without affecting the intrinsic conductivity of MXene. As a result, the representative VOx-V2C/S electrode enables a high volumetric capacity (offering 1645.98 mAh cm-3 at 0.2 C) and cycling stability (retaining 631.17 mAh cm-3 after 1500 cycles at 2.0 C with a capacity decay of 0.03% per cycle). More encouragingly, 3D-printed sulfur electrodes harnessing VOx-V2C hosts readily harvest an areal capacity of 9.74 mAh cm-2 at 0.05 C under an elevated sulfur loading of 10.78 mg cm-2, holding promise for the development of practically viable Li-S batteries.

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