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1.
Small ; 20(13): e2307291, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37964162

RESUMEN

Normally, only noncentrosymmetric structure of the materials can potentially be piezoelectric. Thus, it is limited in the field of piezoelectricity for the centrosymmetric structure of the material. In this work, the performance of piezoelectricity is successfully achieved from centrosymmetric SrFeO3- x by modulating oxygen vacancies, which have a surface piezoelectric potential up to 93 mV by using Kelvin-probe force microscopy (KPFM). Moreover, the piezoelectric effects of SrFeO3- x are also evaluated by piezoelectric catalytic effect and density functional theory calculations (DFT). The results show that the piezo-catalytic degradation of tetracycline reaches 96% after 75 min by ultrasonic mechanical vibration and the production of H2O2 by SrFeO3- x piezoelectric synthesis could reach 1821 µmol L-1. In addition, the DFT results indicate that the intrinsic effect of oxygen vacancies effectively promotes the adsorption and activation of O2 and H2O as well as intermediates and improves the piezoelectric catalytic activity. This work provides an effective basis for realizing the piezoelectricity of centrosymmetric materials and regulating the development of piezoelectric catalytic properties.

2.
Small ; : e2402317, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38988143

RESUMEN

Here, the poly (l-lactic acid) (PLLA) membrane with multi-structured networks (MSN) is successfully prepared by electrospinning technology for the first time. It is composed of micron-sized ribbon-structured fibers and ultrafine nanofibers with a diameter of tens of nanometers, and they are connected to form the new network structure. Thanks to the special fiber morphology and structure, the interception and electrostatic adsorption ability for against atmospheric particulate matter (PM) are significantly enhanced, and the resistance to airflow is reduced due to the "slip effect" caused by ultrafine nanofibers. The PLLA MSN membrane shows excellent filtration performance with ultra-high filtration efficiency (>99.9% for PM2.5 and >99.5% for PM0.3) and ultra-low pressure drop (≈20 Pa). It has demonstrated filtration performance that even exceeds current non-biodegradable polymer materials, laying the foundation for future applications of biodegradable PLLA in the field of air filtration. In addition, this new structure also provides a new idea for optimizing the performance of other polymer materials.

3.
Blood ; 139(24): 3493-3504, 2022 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-35344583

RESUMEN

Hemophagocytic lymphohistiocytosis (HLH) is a lethal disorder characterized by hyperinflammation. Recently, ruxolitinib (RUX), targeting key cytokines in HLH, has shown promise for HLH treatment. However, there is a lack of robust clinical trials evaluating its efficacy, especially its utility as a frontline therapy. In this study (www.chictr.org.cn, ChiCTR2000031702), we designed ruxolitinib as a first-line agent for pediatric HLH and stratified the treatment based on its early response. Fifty-two newly diagnosed patients were enrolled. The overall response rate (ORR) of ruxolitinib monotherapy (day 28) was 69.2% (36/52), with 42.3% (22/52) achieving sustained complete remission (CR). All responders achieved their first response to ruxolitinib within 3 days. The response to ruxolitinib was significantly associated with the underlying etiology at enrollment (P = .009). Epstein-Barr virus (EBV)-HLH patients were most sensitive to ruxolitinib, with an ORR of 87.5% (58.3% in CR). After ruxolitinib therapy, 57.7% (30/52) of the patients entered intensive therapy with additional chemotherapy. Among them, 53.3% (16/30) patients achieved CR, and 46.7% (14/30) patients dominated by chronic active EBV infection-associated HLH (CAEBV-HLH) developed refractory HLH by week 8. The median interval to additional treatment since the first ruxolitinib administration was 6 days (range, 3-25 days). Altogether, 73.1% (38/52) of the enrolled patients achieved CR after treatment overall. The 12-month overall survival (OS) for all patients was 86.4% (95% confidence interval [CI], 77.1% to 95.7%). Ruxolitinib had low toxicity and was well tolerated compared with intensive chemotherapy. Our study provides clinical evidence for ruxolitinib as a frontline agent for pediatric HLH. The efficacy was particularly exemplified with stratified regimens based on the early differential response to ruxolitinib. This study was registered in the Chinese Clinical Trials Registry Platform (http://www.chictr.org.cn/) as ChiCTR2000031702.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Linfohistiocitosis Hemofagocítica , Niño , Infecciones por Virus de Epstein-Barr/complicaciones , Herpesvirus Humano 4 , Humanos , Linfohistiocitosis Hemofagocítica/diagnóstico , Nitrilos , Pirazoles/efectos adversos , Pirimidinas
4.
Br J Haematol ; 202(1): 135-146, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37062931

RESUMEN

Frequent germline mutations of HAVCR2, recently identified in subcutaneous panniculitis-like T-cell lymphoma (SPTCL), are associated with an increased risk of hemophagocytic lymphohistiocytosis (HLH). However, SPTCL-HLH represents a challenge because of the difficulties in treatment with poor survival. Its malignant nature, specifically harbouring HAVCR2 mutations, has also been questioned. To better understand its pathology and treatment, we analysed the clinical data of six patients diagnosed at our centre. The median age at onset was 10.5 years (range, 0.8-12.4). Five patients presented with skin lesions of subcutaneous nodules/plaques and/or ulceration. All patients developed HLH; notably, one infant only had HLH without skin involvement. Histopathologically, only two patients were diagnosed with SPTCL and three were reported as panniculitis with no sufficient evidence of lymphoma. Genetically, germline homozygous mutation of HAVCR2 (p.Y82C) was identified in all patients, with a median diagnosis time of 4.6 months. All patients initially received corticosteroids, immunosuppressants or chemotherapy, achieving unfavourable responses. Strikingly, they responded well to ruxolitinib targeting inflammatory cytokines, allowing rapid disease resolution and/or long-term maintenance of remission. The excellent efficacy of ruxolitinib highlights this disease as an inflammatory condition instead of neoplastic nature and indicates novel agents targeting key inflammatory pathways as an encouraging approach for this disease entity.


Asunto(s)
Linfohistiocitosis Hemofagocítica , Paniculitis , Niño , Preescolar , Humanos , Lactante , Mutación de Línea Germinal , Receptor 2 Celular del Virus de la Hepatitis A/genética , Linfohistiocitosis Hemofagocítica/tratamiento farmacológico , Linfohistiocitosis Hemofagocítica/genética , Linfohistiocitosis Hemofagocítica/complicaciones , Paniculitis/tratamiento farmacológico , Paniculitis/genética
5.
Small ; : e2307810, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38050940

RESUMEN

The technical synergy between flexible sensing paper and triboelectric nanogenerator (TENG) in the next stage of artificial intelligence Internet of Things engineering makes the development of intelligent sensing paper with triboelectric function very attractive. Therefore, it is extremely urgent to explore functional papers that are more suitable for triboelectric sensing. Here, a cellulose nanocrystals (CNCs) reinforced PVDF hybrid paper (CPHP) is developed by electrospinning technology. Benefitting from the unique effects of CNCs, CPHP forms a solid cross-linked network among fibers and obtains a high-strength (25 MPa) paper-like state and high surface roughness. Meanwhile, CNCs also improve the triboelectrification effect of CPHP by assisting the PVDF matrix to form more electroactive phases (96% share) and a higher relative permittivity (17.9). The CPHP-based TENG with single electrode configuration demonstrates good output performance (open-circuit voltage of 116 V, short-circuit current of 2.2 µA and power density of 91 mW m-2 ) and ultrahigh pressure-sensitivity response (3.95 mV Pa-1 ), which endows CPHP with reliable power supply and sensing capability. More importantly, the CPHP-based flexible self-powered tactile sensor with TENG array exhibits multifunctional applications in imitation Morse code compilation, tactile track recognition, and game character control, showing great prospects in the intelligent inductive device and human-machine interaction.

6.
Small ; 19(49): e2304086, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37612815

RESUMEN

Space charge transfer of heterostructures driven by the work-function-induced built-in field can regulate the electronic structure of catalysts and boost the catalytic activity. Herein, an epitaxial heterojunction catalyst of CoO/Mo2 C with interfacial electron redistribution induced by work functions (WFs) is constructed for overall water splitting via a novel top-down strategy. Theoretical simulations and experimental results unveil that the WFs-induced built-in field facilitates the electron transfer from CoO to Mo2 C through the formed "Co─C─Mo" bond at the interface of CoO/Mo2 C, achieving interfacial electron redistribution, further optimizing the Gibbs free energy of primitive reaction step and then accelerating kinetics of hydrogen evolution reaction (HER). As expected, the CoO/Mo2 C with interfacial effects exhibits excellent HER catalytic activity with only needing the overpotential of 107 mV to achieve 10 mA cm-2 and stability for a 60-h continuous catalyzing. Besides, the assembled CoO/Mo2 C behaves the outstanding performance toward overall water splitting (1.58 V for 10 mA cm-2 ). This work provides a novel possibility of designing materials based on interfacial effects arising from the built-in field for application in other fields.

7.
Langmuir ; 39(19): 6885-6894, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37129447

RESUMEN

Traditional SrTiO3 (STO) materials have high brittleness and poor deformation resistance. In this work, macroscopically flexible iron-doped SrTiO3 (SFTO) nanofibrous membranes were prepared by electrospinning and calcination, which can be easily isolated and can maintain integrity to recycle as photocatalysts. Moreover, the SFTO nanofibrous membranes showed enhanced photocatalytic performance under strong acids (pH = 2) and strong alkalis (pH = 12). The SFTO nanofibrous membranes increased the catalytic rate of Congo red (CR) dye by about 10 times in visible light. The mechanism of photocatalytic activity enhancement was discussed by the combined effects of hydroxyl radicals and superoxide radicals. The successful preparation of SFTO nanofibrous membranes has offered a simple and economical approach to photocatalysis as well as environmental remediation.

8.
Cytokine ; 149: 155729, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34673333

RESUMEN

OBJECT: Goal of this research was to investigate values of serum cytokines in childhood HLH with different triggers, with the expectation to find secretion spectrum of 5 main types of underlying diseases. METHOD: 118 newly diagnosed HLH were included, and serum concentrations of 6 cytokines were tested before treatment began. Absolute cytokine levels and ratios between them were then studied in the HLH groups collectively and separately RESULTS: In general, IFN-γ, IL-10 and IL-6 showed differences among 5 HLH groups. Specifically, relative levels of these three cytokines to each other were meaningful in distinguishing 4 types of HLH. Level of IL-6 was higher than those of IFN-γ or IL-10 in HLH driven by Systemic auto-inflammatory disorders (SAIDs) or Langerhans Cell Histiocytosis (LCH), while primary HLH and EBV-HLH shared elevated ratio of IL-10 to IL-6. Although more than one distinctive ratios were found in 3 HLH groups, combination of these parameters didn't offer optimal balance between sensitivity and specificity. CONCLUSION: As a group of easily gained laboratory findings, cytokine levels were reliable in the procedure of roughly classifying HLH cases with the help of patients' clinical phenotype. However, adequate data is still needed to explore the significance of these indicators in identifying one particular underlying disease accurately.


Asunto(s)
Citocinas/sangre , Linfohistiocitosis Hemofagocítica/sangre , Células TH1/metabolismo , Células Th2/metabolismo , Adolescente , Recuento de Células Sanguíneas/métodos , Niño , Preescolar , Femenino , Humanos , Lactante , Interferón gamma/sangre , Interleucina-10/sangre , Interleucina-6/sangre , Masculino , Sensibilidad y Especificidad , Balance Th1 - Th2/fisiología
9.
Pestic Biochem Physiol ; 181: 105012, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35082035

RESUMEN

Due to its biological activity, carvacrol (CAR) is widely used in medicine, agriculture, and forestry. Our previous studies showed that in Lymantria dispar larvae, CAR treatment can induce the production of antifeedants and lead to growth inhibition and death of larvae. However, the effect CAR exerts on RNA levels in L. dispar larvae remains unclear. In this study, the Illumina HiSeq4000 sequencing platform was used to sequence the total RNA of L. dispar larvae. A total of six cDNA libraries (three treatments and three controls) were established and 39,807 genes were generated. Compared with the control group, 296 differentially expressed genes (DEGs) (142 up-regulated and 154 down-regulated) were identified after CAR treatment. GO and KEGG enrichment analyses showed that these DEGs mainly clustered in the metabolism of xenobiotics, carbohydrates, and lipids. Furthermore, 12 DEGs were found to be involved in detoxification, including six cytochrome P450s, two esterases, one glutathione peroxidase, one UDP-glycosyltransferase gene, and two genes encoding heat shock proteins. The expression levels of detoxification genes changed under CAR treatment (especially P450s), which further yielded candidate genes for explorations of the insecticidal mechanism of CAR. The reliability of transcriptome data was verified by qRT-PCR. The enzyme activities of CYP450 and acid phosphatase significantly increased (by 38.52 U/mg·prot and 0.12 µmol/min·mg, respectively) 72 h after CAR treatment. However, the activity of alkaline phosphatase did not change significantly. These changes in enzyme activity corroborated the reliability of the transcriptome data at the protein level. The results of GO enrichment analysis of DEGs indicated that CAR influenced the oxidation-reduction process in L. dispar larvae. Furthermore, CAR can cause oxidative stress in L. dispar larvae, identified through the determination of peroxidase and polyphenol oxidase activities, total antioxidant capacity, and hydrogen peroxide content. This study provides useful insight into the insecticidal mechanism of CAR.


Asunto(s)
Mariposas Nocturnas , Transcriptoma , Animales , Cimenos , Perfilación de la Expresión Génica , Larva/genética , Mariposas Nocturnas/genética , Reproducibilidad de los Resultados
10.
Plant Dis ; 2022 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-35108070

RESUMEN

Pinus sylvestris var. mongolica Litv. (Pinales: Pinaceae) is an excellent tree for soil and water conservation in Northeast China. The Honghua'erji area in Inner Mongolia is the "hometown of P. sylvestris var. mongolica", however, in recent years, coniferous diseases of P. sylvestris var. mongolica have frequently occurred here. During the investigation, it was found that some black spot needle blight had been observed in addition to the common blight caused by Sphaeropsis sapinea. From May to September 2020, black spot needle blight was found on hundreds of P. sylvestris var. mongolica trees in four forest farms, and the infection rate among the forests was 24.58 % (n=240). This disease first appeared on the upper part of the needles, and the needles then became withered and gradually showed light black spots, although they remained green. As the disease progressed, the needles eventually died and turned gray with many dark black spots. Fungal isolate named YJ-1 was obtained from infected needles of symptomatic pine trees, and a voucher specimen was deposited in Heilongjiang Province Key Laboratory of Forest Protection. Microscopic observation showed the conidia were 3-septate (4 cells) clavate spindles that measured 23.9 µm (20.8-25.9) × 5.9 µm (4.5-8.2) (n=50). The middle two cells were dark brown, and the septa were darker than the cells. Both apical and basal cells were hyaline. The apical cell had 2-4 appendages (mostly 3), and the basal cell had a truncate base (n=50). The cultural characteristics on potato dextrose agar medium were flat off-white and dense in 3-5 d. At approximately 5-7 d, the reverse side of the colony turned pale to slightly luteous. Superficial black acervuli were distributed in the center of the mature colonies after 10 d. Morphological, cultural and microscopic characteristics observed were similar of Heterotruncatella spartii (basionym: Truncatella spartii) reported by Hlaiem et al (2019). To further identify, total DNA was extracted and the internal transcribed spacer region (ITS-rDNA) was amplified by PCR using the primers ITS1/ITS4 and sequenced for BLASTn analysis and phylogenetic tree construction. The resulting 564 bp sequence (GenBank Accession No. OL662864) had 99.24% (521/525) to H. spartii MFLUCC 15-0537, with bootstrap support of at least 94% using the Neighbor-Joining algorithm by MEGA-X (Felsenstein, 1985). The fungus was identified as H. spartii based on morphology and molecular methods. A pathogenicity test was conducted by preparing a conidial suspension of 2.0 × 107 conidia/mL. The suspension was sprayed onto the needles of 20 pots of annual P. sylvestris ar. mongolica seedlings, and the control was sprayed with sterile water. Then the seedlings were placed in a constant temperature room at 25 °C. After 30 d, typical symptoms appeared on 11 inoculated needles, while the control needles remained symptomless. After 50 d, the re-isolation infection rate reached 66.7 %. The fungus present on the inoculated seedlings was morphologically identical to that originally observed on diseased pines, fulfilling Koch's postulates. The fungus was isolated from Spartium junceum for the first time and designated Truncatella spartii (Senanayake et al, 2015). It was then renamed H. spartii (Liu et al, 2019) and has been reported to infect P. pinea in Tunisia (Hlaiem et al, 2019). To our knowledge, this is the first report of H. spartii causing black spot needle blight on P. sylvestris var. mongolica in China and worldwide.

11.
J Am Chem Soc ; 143(32): 12800-12808, 2021 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-34369752

RESUMEN

In spite of the excellent electrochemical performance in lithium-ion batteries (LIBs), transition-metal compounds usually show inferior capacity and cyclability in sodium-ion batteries (SIBs), implying different reaction schemes between these two types of systems. Herein, coupling operando magnetometry with electrochemical measurement, we peformed a comprehensive investigation on the intrinsic relationship between the ion-embedding mechanisms and the electrochemical properties of the typical FeS2/Na (Li) cells. Operando magnetometry together with ex-situ transmission electron microscopy (TEM) measurement reveal that only part of FeS2 is involved in the conversion reaction process, while the unreactive parts form "inactive cores" that lead to the low capacity. Through quantification with Langevin fitting, we further show that the size of the iron grains produced by the conversion reaction are much smaller in SIBs than that in LIBs, which may lead to more serious pulverization, thereby resulting in worse cycle performance. The underlying reason for the above two above phenomena in SIBs is the sluggish kinetics caused by the larger Na-ion radius. Our work paves a new way for the investigation of novel SIB materials with high capacity and long durability.

12.
Haematologica ; 106(7): 1892-1901, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32732367

RESUMEN

Hemophagocytic lymphohistiocytosis (HLH) is an immune-regulatory disorder characterized by excessive production of inflammatory cytokines. The treatment recommendations of the HLH-1994 and HLH-2004 protocols have long been used in HLH therapy, but some patients still do not respond well to or have unacceptable side effects from conventional therapies. It is believed that cytokine-targeted strategies that directly target disease-driving pathways will be promising options for HLH. This prospective study aimed to investigate the efficacy and safety of ruxolitinib, a Janus kinase (JAK) 1/2 inhibitor, as a front-line therapy in children with secondary HLH. Twelve newly diagnosed patients without previous treatment were enrolled in this study with a median follow-up of 8.2 (7.1-12.0) months, including 8 cases of Epstein-Barr virus associated HLH (EBV-HLH), 2 cases of autoinflammatory disorder (AID)- associated HLH, and 2 cases of unknown etiology. Patients received oral ruxolitinib dosed on 2.5 mg, 5 mg or 10 mg twice daily depending on the body weight for 28 consecutive days. The overall response rate at the end of treatment (day 28) was 83.3% (10/12), with 66.7% (8/12) in complete response (CR), 8.3% (1/12) in partial response (PR), and 8.3% (1/12) in HLH improvement. Among the patients achieving CR, 87.5% (7/8) maintained CR condition for>6 months, and one patient with EBV-HLH relapsed following CR. For the EBV-HLH subgroup, all 8 patients responded to ruxolitinib, with a CR rate of 75% and a PR rate of 25%. Two patients with AID-associated HLH had quite different responses, with one showing reversal of the HLH abnormalities soon and the other showing no improvement, as did the two cases of unknown etiology. Patients who had no response or discontinued ruxolitinib all responded well to the subsequent HLH-1994 regimen. The expected 6-month event-free survival (EFS) rate was 58.3%±10.2%. No serious adverse effects were reported. Our study provides further support for the possibility of ruxolitinib targeted therapy for secondary HLH in children. This study was registered in the Chinese Clinical Trials Registry Platform (http://www.chictr.org.cn/) as ChiCTR2000029977.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Linfohistiocitosis Hemofagocítica , Niño , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/tratamiento farmacológico , Herpesvirus Humano 4 , Humanos , Linfohistiocitosis Hemofagocítica/tratamiento farmacológico , Nitrilos , Proyectos Piloto , Estudios Prospectivos , Pirazoles , Pirimidinas
13.
Nanotechnology ; 33(2)2021 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-34614481

RESUMEN

Biofuel cell (BFC) is a kind of bio-cell based on biological enzymes. The enzyme as a catalyst can interconvert renewable and sustainable energy into each other more rapidly, such as the biochemical energy in glucose and ethanol into electrical energy. In this work, artificial blood vessel and fuel cell are based on polyaniline/thermoplastic polyurethane (PANI/TPU) fiber membrane with an average fiber diameter of 1300 nm, a film thickness of 167µm, and a permeability of 18.4 mm s-1. The PANI/TPU fiber membrane was prepared by electrospinning and followedin situpolymerization. The membrane has good flexibility and mechanical properties, and can be stretched up to 200%. The advantages of good hydrophilicity, biocompatibility and high porosity make it possible to efficiently load glucose oxidase and laccase. The prepared BFC can stably output a voltage of 50 mV in simulated blood, and the output electrical signal changes significantly with the change of glucose concentration, which may be used in implantable devices or blood glucose monitoring.

14.
BMC Pediatr ; 21(1): 253, 2021 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-34058999

RESUMEN

BACKGROUND: Griscelli syndrome type 2 (GS2) is a rare autosomal recessive disease caused by mutations in RAB27A gene. It is primarily characterized by a combination of partial albinism, hemophagocytic lymphohistiocytosis (HLH) or other immunodeficiency. However, neurological involvement at onset in GS2 and treatment has rarely been described. CASE PRESENTATION: We describe a 3-year-old boy with GS2 in an Asian Chinese family. He presented with progressive neurological abnormalities following unremitting fever at onset. He developed HLH during the clinical course. A novel homozygous mutation (c.1 A > G) in RAB27A gene was subsequently identified. He was then treated by HLH-1994 protocol combined with ruxolitinib and experienced a dramatic remission. He subsequently underwent a successful haploidentical hematopoietic stem cell transplantation and stayed at a good condition. CONCLUSIONS: We reported an atypical form of GS2 manifesting as severe central nervous system involvement at onset and subsequent HLH, which was successfully rescued in time. This case also highlights the need for early consideration of immunologic and genetic evaluation for HLH in unexplained neuroinflammation in the diagnostic work up.


Asunto(s)
Linfohistiocitosis Hemofagocítica , Piebaldismo , Enfermedades de Inmunodeficiencia Primaria , Preescolar , Humanos , Linfohistiocitosis Hemofagocítica/diagnóstico , Linfohistiocitosis Hemofagocítica/genética , Linfohistiocitosis Hemofagocítica/terapia , Masculino , Piebaldismo/complicaciones , Piebaldismo/diagnóstico , Piebaldismo/genética , Proteínas rab27 de Unión a GTP/genética
15.
Pestic Biochem Physiol ; 175: 104859, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33993955

RESUMEN

Vanillin is a natural antimicrobial agent; however, there are few reports on its antifungal effect on postharvest pathogenic fungi. This study aimed to investigate the in vivo and in vitro antifungal activities of vanillin against gray mold (caused by B. cinerea) and black rot (caused by A. alternata) of cherry tomato fruit and to explain its possible mechanism of action. Vanillin strongly inhibits Botrytis cinerea and Alternaria alternata mycelial growth, spore germination, and germ tube elongation in a concentration-dependent manner (P<0.05). In vivo experiments showed that 4000 mg L-1 vanillin treatment inhibited cherry tomato gray mold and black rot occurrence. Besides, intercellular electrolytes, soluble proteins, and soluble sugars leakage indicated that 50 or 100 mg L-1 vanillin treatment increased Botrytis cinerea and Alternaria alternata membrane permeability. The increase of malondialdehyde and hydrogen peroxide contents confirmed that 50 or 100 mg L-1 vanillin treatment damages the pathogen membranes. Importantly, vanillin treatment inhibited the pathogenicity-related enzyme activities of the two pathogens to reduce their infection ability, among them PL enzyme activity in A. alternata was most inhibited, reducing by 94.7 % at 6 h treated with 100 mg L-1 vanillin. The hyphae morphology of the two pathogens changed, the mycelia were severely damaged, and the hyphae surface was deformed, shrunk, or even broken after 100 mg L-1 vanillin treatment. In summary, vanillin had a substantial inhibitory effect on postharvest gray mold and black rot in cherry tomato fruit. Therefore, vanillin can be an effective alternative to prevent and control cherry tomato postharvest diseases.


Asunto(s)
Solanum lycopersicum , Alternaria , Benzaldehídos , Botrytis , Frutas , Enfermedades de las Plantas
16.
New Phytol ; 225(1): 385-399, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31429090

RESUMEN

Plant microRNAs (miRNAs) regulate vital cellular processes, including responses to extreme temperatures with which reactive oxygen species (ROS) are often closely associated. In the present study, it was found that aberrant temperatures caused extensive changes in abundance to numerous miRNAs in banana fruit, especially the copper (Cu)-associated miRNAs. Among them, miR528 was significantly downregulated under cold stress and it was found to target genes encoding polyphenol oxidase (PPO), different from those identified in rice and maize. Expression of PPO genes was upregulated by > 100-fold in cold conditions, leading to ROS surge and subsequent peel browning of banana fruit. Extensive comparative genomic analyses revealed that the monocot-specific miR528 can potentially target a large collection of genes encoding Cu-containing proteins. Most of them are actively involved in cellular ROS metabolism, including not only ROS generating oxidases, but also ROS scavenging enzymes. It also was demonstrated that miR528 has evolved a distinct preference of target genes in different monocots, with its target site varying in position among/within gene families, implying a highly dynamic process of target gene diversification. Its broad capacity to target genes encoding Cu-containing protein implicates miR528 as a key regulator for modulating the cellular ROS homeostasis in monocots.


Asunto(s)
Cobre/metabolismo , Genes de Plantas , Homeostasis , MicroARNs/metabolismo , Musa/genética , Proteínas de Plantas/genética , Especies Reactivas de Oxígeno/metabolismo , Secuencia Conservada/genética , Evolución Molecular , Regulación de la Expresión Génica de las Plantas , Redes Reguladoras de Genes , Lacasa/genética , MicroARNs/genética , Modelos Biológicos , Oxidación-Reducción , Proteínas de Plantas/metabolismo , Estrés Fisiológico/genética , Temperatura
17.
J Nanobiotechnology ; 18(1): 111, 2020 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-32778125

RESUMEN

BACKGROUND: Electrospun (e-spun) nanofibers for wound dressing have attracted wide attention due to its large specific surface area, large porosity and breathability. Compared with solution electrospinning (e-spinning), melt e-spinning is more bio-friendly without toxic solvent participation, which provides the possibility of in situ e-spinning on wounds directly. However, previously reported melt e-spinning devices were usually bulky and cumbersome due to their necessary heating unit, and different components were separated to avoid electrostatic interference. RESULTS: In this article, we report on a self-powered hand-held melt e-spinning gun which can work without any external power supply (outdoors). The problem of electrostatic interference for this integrated device was solved by using a special high heat transfer insulation unit. The apparatus is easy and safe to operate by a single hand due to its small volume (24 × 6 × 13 cm3) and light weight (about 450 g). Some biodegradable polymers, for example, polycaprolactone (PCL) fibers were successful e-spun onto wounds directly by using this dressing gun. CONCLUSIONS: PCL fibrous membrane has good biocompatibility and can be in situ electrospun to wound surface as a wound dressing by the portable melt e-spinning gun. Besides wound dressing, this hand-held melt e-spinning gun may be used in 3D printing and experimental teaching demonstration aids.


Asunto(s)
Vendajes , Técnicas Electroquímicas , Nanofibras , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Diseño de Equipo , Fibroblastos/efectos de los fármacos , Masculino , Nanofibras/química , Nanofibras/toxicidad , Poliésteres/química , Poliésteres/toxicidad , Porosidad , Ratas , Ratas Sprague-Dawley , Temperatura
18.
Pestic Biochem Physiol ; 169: 104639, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32828363

RESUMEN

Sodium pheophorbide a (SPA) is a new alternative fungicide with low toxicity and high efficiency, which has high fungicidal activity against Pestalotiopsis neglecta, a pathogen that causes black spot needle blight of Pinus sylvestris var. mongolica. To utilize SPA for plant disease control, understanding its antifungal mechanism is essential. Six cDNA libraries were constructed from 3 d-old P. neglecta mycelia (three SPA-infected and three untreated groups) and 29,850 expressed genes were obtained by Illumina HiSeq4000 sequencing. Compared with controls, 3268 differentially expressed genes (DEGs) were identified in SPA-treated groups, including 1879 upregulated and 1389 downregulated genes. Most DEGs were involved in the metabolism of amino acids, carbohydrates, and lipids, as well as cell structure and genetic information processing. These findings were further confirmed by decreased conductivity, RNA and protein content, and activities of nicotinamide adenine dinucleotide-dependent malate dehydrogenase, citrate synthase, isocitrate dehydrogenase, and succinate dehydrogenase. Moreover, qRT-PCR verified the reliability of the transcriptome results. After treatment with SPA at different concentrations for 60 min, the expressions of three cell wall degrading enzyme-related genes (PnEG, PnBG, and PnPG) were all suppressed. Overall, this study provided insights into the molecular mechanisms through which SPA inhibits P. neglecta, increasing the possibility of developing SPA into an effective fungicide in the future.


Asunto(s)
Sodio , Transcriptoma , Pared Celular , Clorofila/análogos & derivados , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Reproducibilidad de los Resultados
19.
Entropy (Basel) ; 22(3)2020 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-33286082

RESUMEN

This paper developed a three-dimensional model to simulate the process of atomization and liquid film formation during the air-blast spray cooling technological process. The model was solved using the discrete phase model method. Several factors including the thermodynamic characteristics of the liquid film as well as the spray quality with different spray mass flow rates under different spray heights were numerically investigated and discussed. The results show that the varied spray height has little effect on the Sauter Mean Diameter (d32) of the spray droplet, while the thermodynamic characteristics of liquid film including the liquid film height, the liquid film velocity, and the liquid film generation rate are sensitive to the change of the spray height. With the growth of spray mass flow rates, d32, the liquid film generation rate and liquid film height become larger, while the liquid film velocity with different spray mass flow rates has a similar velocity distribution, indicating that the spray mass flow rate has little effect on the liquid film velocity. The average d32 of droplet size shows a sharp drop when sprayed from the nozzle in a short period of time (<1.5 ms), then approaching smoothness, below a value of 40 µ m , the spray status tends to be stable.

20.
Entropy (Basel) ; 22(1)2020 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-33285846

RESUMEN

Scientific experimental racks are an indispensable supporter in space stations for experiments with regard to meeting different temperature and humidity requirements. The diversity of experiments brings enormous challenges to the thermal control system of racks. This paper presents an indirect coupling thermal control single-phase fluid loop system for scientific experimental racks, along with fuzzy incremental control strategies. A dynamic model of the thermal control system is built, and three control strategies for it, with different inputs and outputs, are simulated. A comparison of the calculated results showed that pump speed and outlet temperature of the cold plate branch are, respectively, the best choice for the control variable and controlled variable in the controller. It showed that an indirect coupling thermal control fluid loop system with a fuzzy incremental controller is feasible for the thermal control of scientific experimental racks in space stations.

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