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Strain engineering is a powerful tool with which to enhance semiconductor device performance1,2. Halide perovskites have shown great promise in device applications owing to their remarkable electronic and optoelectronic properties3-5. Although applying strain to halide perovskites has been frequently attempted, including using hydrostatic pressurization6-8, electrostriction9, annealing10-12, van der Waals force13, thermal expansion mismatch14, and heat-induced substrate phase transition15, the controllable and device-compatible strain engineering of halide perovskites by chemical epitaxy remains a challenge, owing to the absence of suitable lattice-mismatched epitaxial substrates. Here we report the strained epitaxial growth of halide perovskite single-crystal thin films on lattice-mismatched halide perovskite substrates. We investigated strain engineering of α-formamidinium lead iodide (α-FAPbI3) using both experimental techniques and theoretical calculations. By tailoring the substrate composition-and therefore its lattice parameter-a compressive strain as high as 2.4 per cent is applied to the epitaxial α-FAPbI3 thin film. We demonstrate that this strain effectively changes the crystal structure, reduces the bandgap and increases the hole mobility of α-FAPbI3. Strained epitaxy is also shown to have a substantial stabilization effect on the α-FAPbI3 phase owing to the synergistic effects of epitaxial stabilization and strain neutralization. As an example, strain engineering is applied to enhance the performance of an α-FAPbI3-based photodetector.
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AIMS: As our comprehension of the intricate relationship between cellular senescence and tumor biology continues to evolve, the therapeutic potential of cellular senescence is gaining increasing recognition. Here, we identify chromobox 4 (CBX4), a Small Ubiquitin-related Modifier (SUMO) E3 ligase, as an antagonist of cellular senescence and elucidate a novel mechanism by which CBX4 promotes drug resistance and malignant progression of gastric cancer (GC). METHODS: In vitro and in vivo models were conducted to investigate the manifestation and impact of CBX4 on cellular senescence and chemoresistance. High-throughput sequencing, chromatin immunoprecipitation, and co-immunoprecipitation techniques were utilized to identify the upstream regulators and downstream effectors associated with CBX4, revealing its intricate regulatory network. RESULTS: CBX4 diminishes the sensitivity of GC cells to cellular senescence, facilitating chemoresistance and GC development by deactivating the senescence-related Hippo pathway. Mechanistically, low-dose cisplatin transcriptionally downregulates CBX4 through CEBPB. In addition, CBX4 preserves the stability and cytoplasm-nuclear transport of YAP1, the key player of Hippo pathway, by inducing SUMO1 modification at K97 and K280, which competitively inhibits YAP1-S127 phosphorylation. CONCLUSIONS: Our study highlights the anti-senescence role of CBX4 and suggests that CBX4 inhibition in combination with low-dose cisplatin has the potential to overcome chemoresistance and effectively restrict GC progression.
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Generation of mammalian red blood cells requires the expulsion of polarized nuclei late in terminal erythroid differentiation. However, the mechanisms by which spherical erythroblasts determine the direction of nuclear polarization and maintain asymmetry during nuclear expulsion are poorly understood. Given the analogy of erythroblast enucleation to asymmetric cell division and the key role of Aurora kinases in mitosis, we sought to investigate the function of Aurora kinases in erythroblast enucleation. We found that AURKA (Aurora kinase A) is abundantly expressed in orthochromatic erythroblasts. Intriguingly, high-resolution confocal microscopy analyses revealed that AURKA co-localized with the centrosome on the side of the nucleus opposite its membrane contact point during polarization and subsequently translocated to the anterior end of the protrusive nucleus upon nuclear exit. Mechanistically, AURKA regulated centrosome maturation and localization via interaction with i-tubulin to provide polarization orientation for the nucleus. Furthermore, we identified ECT2 (epithelial cell transforming 2), a guanine nucleotide exchange factor, as a new interacting protein and ubiquitination substrate of AURKA. After forming the nuclear protrusion, AURKA translocated to the anterior end of the protrusive nucleus to directly degrade ECT2, which is partly dependent on kinase activity of AURKA. Moreover, knockdown of ECT2 rescued impaired enucleation caused by AURKA inhibition. Our findings have uncovered a previously unrecognized role of Aurora kinases in the establishment of nuclear polarization and eventual nuclear extrusion and provide new mechanistic insights into erythroblast enucleation.
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OBJECTIVE: Children with self-limited epilepsy characterized by centrotemporal spikes (SeLECTS) exhibit cognitive deficits in memory during the active phase, but there is currently a lack of studies and techniques to assess their memory development after well-controlled seizures. In this study, we employed eye-tracking techniques to investigate visual memory and its association with clinical factors and global intellectual ability, aiming to identify potential risk factors by examining encoding and recognition processes. METHODS: A total of 26 recruited patients diagnosed with SeLECTS who had been seizure-free for at least 2 years, along with 24 control subjects, underwent Wechsler cognitive assessment and an eye-movement-based memory task while video-electroencephalographic (EEG) data were recorded. Fixation and pupil data related to eye movements were utilized to detect distinct memory processes and subsequently to compare the cognitive performance of patients exhibiting different regression patterns on EEG. RESULTS: The findings revealed persistent impairments in visual memory among children with SeLECTS after being well controlled, primarily observed in the recognition stage rather than the encoding phase. Furthermore, the age at onset, frequency of seizures, and interictal epileptiform discharges exhibited significant correlations with eye movement data. SIGNIFICANCE: Children with SeLECTS exhibit persistent recognition memory impairment after being well controlled for the disease. Controlling the frequency of seizures and reducing prolonged epileptiform activity may improve memory cognitive development. The application of the eye-tracking technique may provide novel insights into exploring memory cognition as well as underlying mechanisms associated with pediatric epilepsy.
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Epilepsia Rolándica , Tecnología de Seguimiento Ocular , Humanos , Niño , Convulsiones/diagnóstico , Cognición , Electroencefalografía/métodos , Trastornos de la Memoria/etiología , Trastornos de la Memoria/complicaciones , Epilepsia Rolándica/complicaciones , Epilepsia Rolándica/psicologíaRESUMEN
BACKGROUND AND PURPOSE: Several previous studies have shown that skin sebum analysis can be used to diagnose Parkinson's disease (PD). The aim of this study was to develop a portable artificial intelligence olfactory-like (AIO) system based on gas chromatographic analysis of the volatile organic compounds (VOCs) in patient sebum and explore its application value in the diagnosis of PD. METHODS: The skin VOCs from 121 PD patients and 129 healthy controls were analyzed using the AIO system and three classic machine learning models were established, including the gradient boosting decision tree (GBDT), random forest and extreme gradient boosting, to assist the diagnosis of PD and predict its severity. RESULTS: A 20-s time series of AIO system data were collected from each participant. The VOC peaks at a large number of time points roughly concentrated around 5-12 s were significantly higher in PD subjects. The gradient boosting decision tree model showed the best ability to differentiate PD from healthy controls, yielding a sensitivity of 83.33% and a specificity of 84.00%. However, the system failed to predict PD progression scored by Hoehn-Yahr stage. CONCLUSIONS: This study provides a fast, low-cost and non-invasive method to distinguish PD patients from healthy controls. Furthermore, our study also indicates abnormal sebaceous gland secretion in PD patients, providing new evidence for exploring the pathogenesis of PD.
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Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/diagnóstico , Enfermedad de Parkinson/patología , Inteligencia Artificial , Aprendizaje AutomáticoRESUMEN
BACKGROUND: Emerging evidence has indicated a link between the gut microbiota and acute lymphoblastic leukaemia (ALL). However, the acute changes in gut microbiota during chemotherapy and the predictive value of baseline gut microbiota in infectious complication remain largely unknown. METHODS: Faecal samples (n = 126) from children with ALL (n = 49) undergoing induction chemotherapy were collected at three timepoints, i.e., initiation of chemotherapy (baseline, T0), 7 days (T1) and 33 days (T2) after initiation of chemotherapy. Gut microbiome profile was performed via metagenomic shotgun sequencing. The bioBakery3 pipeline (Kneaddata, Metaphlan 3 and HUMAnN) was performed to assign taxonomy and functional annotations. Gut microbiome at T0 were used to predict infection during chemotherapy. RESULTS: The microbial diversities and composition changed significantly during chemotherapy, with Escherichia coli, Klebsiella pneumoniae and Bifidobacterium longum being the most prominent species. The microbial metabolic pathways were also significantly altered during chemotherapy, including the pathway of pyruvate fermentation to acetate and lactate, and assimilatory sulfate reduction pathway. The receiver operating characteristic (ROC) models based on Bifidobacterium longum at T0 could predict infectious complications during the first month of chemotherapy with the area under the curve (AUC) of 0.720. CONCLUSIONS: Our study provides new insights into the acute changes in microbial and functional characteristics in children with ALL during chemotherapy. The baseline gut microbiota could be potential biomarkers for infections during chemotherapy. TRIAL REGISTRATION: The study was approved by the Ethics Committee of Zhujiang Hospital, Southern Medical University (2021-KY-171-01) and registered on http://www.chictr.org.cn (ChiCTR2200065406, Registration Date: November 4, 2022).
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Heces , Microbioma Gastrointestinal , Metagenómica , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Microbioma Gastrointestinal/efectos de los fármacos , Femenino , Masculino , Heces/microbiología , Niño , Preescolar , Quimioterapia de Inducción , Biomarcadores , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Metagenoma , Escherichia coli/genética , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/efectos de los fármacosRESUMEN
The industrialization of hydrogen production through dark fermentation of food waste faces challenges, such as low yields and unpredictable fermentation processes. Biochar has emerged as a promising green additive to enhance hydrogen production in dark fermentation. Our study demonstrated that the introduction of Fe-modified biochar (Fe-L600) significantly boosted hydrogen production during thermophilic dark fermentation of food waste. The addition of Fe-L600 led to a remarkable 31.19% increase in hydrogen yield and shortened the time needed for achieving stabilization of hydrogen production from 18 h to 12 h. The metabolite analysis revealed an enhancement in the butyric acid pathway as the molar ratio of acetic acid to butyric acid decreased from 3.09 to 2.69 but hydrogen yield increased from 57.12 ± 1.48 to 76.78 ± 2.77 mL/g, indicating Fe-L600 improved hydrogen yield by regulating crucial metabolic pathways of hydrogen production. The addition of Fe-L600 also promoted the release of Fe2+ and Fe3+ and increased the concentrations of Fe2+ and Fe3+ in the fermentation system, which might promote the activity of hydrogenase and ferredoxin. Microbial community analysis indicated a substantial increase in the relative abundance of Thermoanaerobacterium after thermophilic dark fermentation. The relative abundances of microorganisms responsible for hydrolysis and acidogenesis were also observed to be improved in the system with Fe-L600 addition. This research provides a feasible strategy for improving hydrogen production of food waste and deepens the understanding of the mechanisms of biochar.
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Carbón Orgánico , Alimento Perdido y Desperdiciado , Eliminación de Residuos , Fermentación , Alimentos , Ácido Butírico , Hidrógeno/metabolismoRESUMEN
Improving the efficiency of antiseizure medication entering the brain is the key to reducing its peripheral toxicity. A combination of intranasal administration and nanomedicine presents a practical approach for treating epileptic seizures via bypassing the blood-brain barrier. In this study, phenytoin (PHT) loaded layered double hydroxide nanoparticles (BSA-LDHs-PHT) were fabricated via a coprecipitation - hydrothermal method for epileptic seizure control. In this study, we expound on the preparation method and characterization of BSA-LDHs-PHT. In-vitro drug release experiment shows both rapid and continuous drug release from BSA-LDHs-PHT, which is crucial for acute seizure control and chronic epilepsy therapy. In-vivo biodistribution assays after intranasal administration indicate excellent brain targeting ability of BSA-LDHs. Compared to BSA-Cyanine5.5, BSA-LDHs-Cyanine5.5 were associated with a higher brain/peripheral ratio across all tested time points. Following intranasal delivery with small doses of BSA-LDHs-PHT, the latency of seizures in the pentylenetetrazole-induced mouse models was effectively improved. Collectively, the present study successfully designed and applied BSA-LDHs-PHT as a promising strategy for treating epileptic seizures with an enhanced therapeutic effect.
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Epilepsia , Nanopartículas , Ratones , Animales , Fenitoína/farmacología , Fenitoína/uso terapéutico , Administración Intranasal , Distribución Tisular , Convulsiones/tratamiento farmacológico , Epilepsia/tratamiento farmacológico , Nanopartículas/uso terapéutico , Hidróxidos/uso terapéuticoRESUMEN
Transplant treatment with chlorantraniliprole (CAP) is a proactive approach to protect transplanted plants from pests during early establishment and has been comprehensively applied in tobacco fields in Guangdong Province, China. However, it is not known whether the high dose of CAP in transplant treatments has lethal or sublethal effects on the generalist predator Rhynocoris fuscipes Fabricius (Hemiptera: Reduviidae). To address this concern, the mortalities of R. fuscipes were assessed when 2nd instar larvae of R. fuscipes were in direct contact with or consuming CAP and when their eggs were exposed to CAP. Furthermore, 2nd instar nymphs R. fuscipes were long-term exposed to CAP until they reached adulthood, and their life table parameters were determined. After exposure to CAP, the activity of detoxification enzymes (P450, CaeE and GST) and the functional respond of R. fuscipes to their preys Agrotis ipsilon larvae were determined. In this study, CAP at all concentrations did not significantly increase the mortality of 2nd instar of R. fuscipes nymphs in comparison with the control. The detoxification enzyme (P450, CarE and GST) activities and the number of A. ipsilon larvae consumed by R. fuscipes in the transplant treatment were not affected by CAP after 3-d or long-term exposure. These results indicated that CAP was harmless to R. fuscipes according to IOBC protocols. However, during the treatment of 2nd instar nymphs with a label rate of 15â¯g AI/ha and a 5× label rate of 75â¯g AI/ha, CAP significantly prolonged the pre-adult and pre-oviposition periods, and treated adults had lower oviposition. Attention should be given to the time interval between transplant treatment and the release of this biocontrol agent into the field to minimize the impact of CAP on the predator R. fuscipes.
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Fertilidad , Insecticidas , Larva , Ninfa , Conducta Predatoria , ortoaminobenzoatos , Animales , ortoaminobenzoatos/toxicidad , Larva/efectos de los fármacos , Insecticidas/toxicidad , Ninfa/efectos de los fármacos , Ninfa/crecimiento & desarrollo , Ninfa/fisiología , Fertilidad/efectos de los fármacos , Conducta Predatoria/efectos de los fármacos , Hemípteros/efectos de los fármacos , Hemípteros/fisiología , China , Femenino , Heterópteros/efectos de los fármacos , Heterópteros/fisiología , Cadena AlimentariaRESUMEN
Potato (Solanum tuberosum L.) is a globally important staple crop, and China has contributed more than 20% of the world's production. In Guangdong Province, potato has become one of the most important winter crops, increased the farmer income. However, the potato were seriously affected by soft rot disease caused by Pectobacterium spp. in the past decade. In February 2024, typical symptoms of potato soft rot were observed on the plants of cultivar "Daxiyang" in Enping City, Guangdong Province, where the disease incidences ranged 3%-5% in the investigated fields. The stems adjacent to the tubes showed typical inky black symptoms, and the plants appeared yellow. The interior of the tubes appeared water-soaked and had developed to overall decay, with an evident smell. Eleven symptomatic plants were collected and used to isolate the causal agents. Pieces of tube tissue (about 5×5 mm) were removed between the rot-symptomatic and non-symptomatic margins, and surface sterilized using 75% ethanol for 30 s and 2% NaClO for 1 min. The pieces were rinsed in sterile water for three times, and then plated on Luria-Bertani (LB) medium agar for 36 h at 30°C. The produced colonies were selected for hypersensitive test on tobacco, and the colonies with a positive reaction were subcultured three times. Two representative strains, EP51-2 and EP51-3, were processed for gene sequencing, including house-keeping genes, danX, leuS, and recA (Portier et al. 2019). The gene sequences (GenBank accessions no. PP870934 to PP870939) of these two representative strains were matched with Pectobacterium aroidearum strain NCPPB 929 (CP166097.1) with identities ranging from 97.15 to 100% and the coverage of 100%. The sequences of three genes were concatenated and used for phylogenetic analyses, along with representative strains from 19 other Pectobacterium species. Phylogenetic analyses supported that EP51-2 and EP51-3 were grouped into P. aroidearum with the representative strains. Koch's postulates were applied to determine the pathogenicity of P. aroidearum strain EP51-2. According to the external inoculation method on potato stems (Czajkowski et al. 2010), each of six pots of healthy potato plants was inoculated at the basal stem with 100 µl of bacterial suspension (108 CFU/ml), while six pots inoculated with LB served as controls. The plants were then kept at 30°C and maintained at 95% humidity. After 2 days, all six plants inoculated with the bacteria exhibited typical symptoms on the stems, which progressed to the collapse of the whole plant; the controls remained symptom-free during the observation. Single colonies reisolated from the symptomatic stem of the inoculated plants were confirmed using PCR and sequencing with recA primers as described above, and the causal agent was identified as P. aroidearum strains, fulfilling Koch's postulates. P. aroidearum has been reported on Chinese cabbage (Xie et al. 2018) and leaf mustard (Chu et al. 2024) in China, as well as on crops in the family Araceae, such as konjac (Wei et al. 2021), taro (Zhou et al. 2022), and Pinellia ternata (Du et al. 2024). To our knowledge, this is the first report of P. aroidearum causing potato soft rot in China. This pathogen has been prevalent in the taro fields in Guangdong Province and has caused severe losses. This report highlights an expansion of the host range for this pathogen. Attention should be focused on this newly emerging pathogen affecting potatoes, and immediate measures should be implemented to control its spread.
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OBJECTIVE: To analyze the prognostic factors of sepsis in children with acute leukemia admitted to the pediatric intensive care unit (PICU) and to compare the efficacy of different scoring systems for predicting the outcome of children. METHODS: Patients with an acute leukemia diagnosis admitted to a tertiary care university hospital PICU due to sepsis during chemotherapy between May 2015 and August 2022 were retrospectively analyzed through an electronic medical record system. RESULTS: During this period, 693 children with acute leukemia initially diagnosed were admitted to the center, and 155 (22.3%) of them were transferred to PICU due to deterioration of the disease during treatment. Total 109 (70.3%) patients were transferred to PICU due to sepsis. Here, 17 patients was excluded (prior treatment from another hospital; referring from other hospitals; discontinued treatment; incomplete medical record). Of the 92 patients studied, the mortality rate was 35.9%. Multivariate analysis revealed that remission status, lactate level, invasive mechanical ventilation (IMV), and inotropic support within 48 hours after PICU transfer were independent risk factors for PICU mortality. The pediatric sequential organ failure assessment (PSOFA) score had the greatest predictive validity for hospital mortality (area under the receiver operating characteristic curve [AUROC]: 0.83, 95% confidence intervals [CI]: 0.74-0.92), followed by the pediatric early warning score (PEWS) (0.82, 0.73-0.91) and pediatric critical illness score (PCIS) (0.79, 0.69-0.88). CONCLUSION: The mortality rate among children with acute leukemia complicated with sepsis is high after being transferred to the PICU. Various scoring systems can be used to monitor the clinical status of patients, identify sepsis early, detect critical illness, and determine the optimal time for transfer to the PICU for supportive treatment, thereby improving the prognosis of these patients.
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Humic acid (HA) has attracted much attention for its electron-competitive effect of quinone groups on anaerobic methanogenesis. This study analyzed the biological "capacitor" to determine how it might effectively reduce electron competition. As biological capacitor-producing additives, three semiconductive materials, including magnetite, hematite, and goethite, were selected. The results showed that hematite and magnetite could significantly alleviate the inhibited methanogenesis caused by the HA model compound anthraquinone-2,6-disulfonate (AQDS). The electrons flowing to methane in hematite-AQDS, magnetite-AQDS, control, sole-AQDS, and goethite-AQDS groups accounted for 81.24, 77.12, 75.42, 70.55, and 56.32% of the total produced electrons, respectively. Hematite addition significantly accelerated the methane production rate (18.97%) compared with sole-AQDS. Electrochemical investigation showed that AQDS might have its oxidation potential reduced by adsorbing on hematite, which results in an energy band bending for hematite and the formation of a biological capacitor. The biological capacitor's integrated electric field helps with the transfer of electrons from reduced AQDS to anaerobic consortia via bulk hematite. Metagenomic and metaproteomic sequencing analyses revealed that the ferredoxin and Mph-reducing hydrogenase in hematite addition increased by 7.16 and 21.91%, respectively, compared to sole-AQDS addition. Accordingly, this research suggested that AH2QDS may re-transfer electrons to methanogens via the biological capacitor and the membrane's Mph-reducing hydrogenase, thus lowering the HA electron competition.
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Sustancias Húmicas , Hidrogenasas , Transporte de Electrón , Óxido Ferrosoférrico , Anaerobiosis , Oxidación-Reducción , Antraquinonas , MetanoRESUMEN
Anaerobic microorganisms use flavin/quinone-based electronic bifurcation (EB) to gain a survival advantage at the thermodynamic limits. However, the contribution of EB to microscopic energy and productivity in the anaerobic digestion (AD) system is unknown. This study demonstrates for the first time that under limited substrate conditions, Fe-driven EB in AD leads to a 40% increase in specific methane production and contributes to 25% ATP accumulation, by analyzing the concentration of EB enzymes such as Etf-Ldh, HdrA2B2C2, and Fd, NADH and actual Gibbs free-energy changes. Differential pulse voltammetry and electron respiratory chain inhibition experiments detected that iron enhanced electron transport in EB by accelerating the activity of flavin, Fe-S clusters, and quinone groups. Other microbial and enzyme genes with EB potential closely related to iron transport have also been found in metagenomes. The potential of EB to accumulate energy and enhance productivity in AD systems was investigated, and metabolic pathways were proposed in the study.
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Ácido Láctico , Quinonas , Ácido Láctico/metabolismo , Anaerobiosis , Flavinas/metabolismo , Hierro , Metano , Reactores BiológicosRESUMEN
From March to June 2022, Fusarium tobacco root rot broke out in Shaoguan Guangdong Province, China, affecting approximately 15% of tobacco production ï¬elds, with an incidence of 24% to 66%. In the early stage, the lower leaves showed chlorosis, and the roots became black. In the later stage, the leaves became browned and withered, the root cortices were broken and shed, and only a small number of roots were left. Eventually, the entire plant died. Six diseased plant samples (cv. yueyan 97) from Shaoguan (113.8°E, 24.8°N) were collected as test materials. The diseased root tissues (4×4 mm) were surface-sterilized using 75% ethanol for 30 s and 2% NaOCl for 10 min, rinsed 3 times with sterile water and incubated for 4 days on potato dextrose agar (PDA) medium at 25 °C. Fungal colonies were subcultured on fresh PDA, grown for the next 5 d and purified by single-spore separation. Eleven isolates with similar morphological characteristics were obtained. Their colonies were white and fluffy, and the bottoms of the culture plates were pale pink after 5 days of incubation. The macroconidia were slender, slightly curved and measured 18.54~45.85 µm×2.35~3.84 µm (n=50), with 3 to 5 septa. The microconidia were oval or spindle shaped, with one to two cells, and measured 5.56~16.76 µm×2.32~3.86 µm (n=50). Chlamydospores were absent. Such characteristics are typical of the genus Fusarium (Booth C, 1971). The SGF36 isolate was chosen for further molecular analysis. The TEF-1α and ß-tubulin genes (Pedrozo et al.2015) were amplified. Based on a phylogenetic tree (neighbor-joining method and 1,000 bootstrap values) obtained using multiplex alignments of concatenations of these two genes from 18 Fusarium species, SGF36 was grouped into a clade with Fusarium fujikuroi strain 12-1 (MK443268.1/MK443267.1) and F. fujikuroi isolate BJ-1 (MH263736.1/MH263737.1). To further identity the isolate, five additional gene sequences (rDNA-ITS (OP862807.1), RPB2, histone 3, calmodulin, and mitochondrial small subunit) (Pedrozo et al.2015), were subjected to BLAST searches in GenBank, and the results indicated that they were most similar to F. fujikuroi sequences, with sequence identities greater than 99%. The phylogenetic tree obtained using six genes except mitochondrial small subunit gene showed that SGF36 was grouped together with four F. fujikuroi strains to form a single clade. Pathogenicity was determined by the inoculation of wheat grains with fungi in potted tobacco plants. The SGF36 isolate was inoculated onto sterilized wheat grains, which were then incubated at 25 °C for 7 d. Thirty wheat grains with fungi were added to 200 g of sterilized soil, which was then mixed well and placed into pots. One six-leaf-stage tobacco seedling (cv. yueyan 97) was planted in each pot. A total of 20 tobacco seedlings were treated. Another 20 control seedlings were treated with wheat grains without fungi. All seedlings were placed in a greenhouse at 25 °C with 90% relative humidity. After 5 d, the leaves of all inoculated seedlings showed chlorosis, and the roots became discolored. No symptoms were observed in the controls. The fungus was reisolated from symptomatic roots and confirmed to be F. fujikuroi based on the TEF-1α gene sequence. No F. fujikuroi isolates were recovered from control plants. F. fujikuroi was previously reported to be associated with rice bakanae disease (Ram et al., 2018), soybean root rot (Zhao et al., 2020) and cotton seedling wilt (Zhu et al., 2020). To our knowledge, this is the first report of F. fujikuroi causing root wilt on tobacco in China. The identification of the pathogen may help to establish appropriate measures for controlling this disease.
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Petunia hybrida is commonly cultivated for ornamental use in urban parks greening and street embellishment in China. In March 2022, 60% of P. hybrida plants cv. Wave Purple (n≈1800) from an ornamental plant nursery under natural conditions in Tianhe district (N 113°21'21", E 23°9'3.5"), Guangzhou, Guangdong Province, China, were affected with soft rot disease. The distribution of the disease was generally uniform. Infected plants initially exhibit small water-soaked lesions at the base of the stem, which then extended to the leaves. Eventually the diseased plant collapsed and died. Nine diseased plants were collected, and affected tissues cut into small fragments (5 × 5 mm), which were disinfested in 75% ethanol (30 s) and 2% sodium hypochlorite (60 s), followed by three rinses with sterile distilled water. The sterilized sections were macerated in 200 µl sterile water, and streaked on Luria-Bertani (LB) agar medium and incubated at 28°C for 48 h. Single colonies were restreaked three times to obtain purified isolation. Sixteen bacterial strains with similar morphology were isolated, and their colonies were yellowish white, round, and convex with smooth surfaces on LB agar plate. The representative strain BDQ1 was selected for further analyses and the 16S rDNA gene (GenBank Accession ON982467) were amplified using primer pair 27F/1492R, revealed above 99% sequence identity with some Pectobacterium brasiliense isolates (GenBank Accession Nos. CP046380(1421/1422), MN393966(1419/1422), and CP020350(1419/1422)) using BLASTn. A multilocus phylogenetic analysis by neighbor-joining method (1,000 bootstrap values) based on six housekeeping gene sequences of gyrA (GenBank Accession No. ON995454), icdA (ON995455), mdh (ON995456), mtlD (ON995457), proA (ON995458), and rpoS genes (ON995459) (Ma et al. 2007; Waleron et al., 2008). The results of phylogenetic analysis showed BDQ1 strain belong to the P. brasiliense clade. Pathogenicity tests were performed on ten healthy P. hybrida cv. Wave Purple plants by injecting 10 µl of bacterial suspensions of BDQ1 (108 CFU/ml) into the stems; another 10 healthy control plants were injected with 10 µl of sterile water. All plants were grown at 25-30°C and 60% humidity in natural light/dark cycle. After 3 d, all inoculated plants showed soft rot symptoms resembling to those observed in the nursery, while control plants remained healthy. Bacteria were successfully reisolated from the symptomatic tissues and identified to be P. brasiliense by PCR mentioned above. P. brasiliense is considered a very aggressive pathogen, which has been reported in Eurasia and Africa (Oulghazi et al. 2021). To our knowledge, this is the first report of P. brasiliense causing bacterial soft rot on P. hybrida in China. This pathogen may pose threat to P. hybrida production in area with warmand humid climate in China. The current study expands the known host range of P. brasiliense and helped raise attention on controlling pathogen spread.
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Shape-controlled synthesis is an effective method for controlling the physicochemical properties of nanomaterials, especially single-crystal nanomaterials, but it is difficult to control the morphology of single-crystal metallic nanomaterials. Silver nanowires (AgNWs) are regarded as key materials for the new generation of human-computer interaction, which can be applied in large-scale flexible and foldable devices, large-size touch screens, transparent LED films, photovoltaic cells, etc. When used on a large scale, the junction resistance will be generated at the overlap between AgNWs and the conductivity will decrease. When stretched, the overlap of AgNWs will be easily disconnected, which will lead to a decrease in electrical conductivity or even system failure. We propose that in situ silver nanonets (AgNNs) can solve the above two problems. The AgNNs exhibited excellent electrical conductivity (0.15 Ωâsq-1, which was 0.2 Ωâsq-1 lower than the 0.35 Ωâsq-1 square resistance of AgNWs) and extensibility (the theoretical tensile rate was 53%). In addition to applications in flexible stretchable sensing and display industries, they also have the potential to be used as plasmonic materials in molecular recognition, catalysis, biomedicine and other fields.
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Nanocables , Humanos , Plata , Catálisis , Conductividad Eléctrica , ElectrodosRESUMEN
The increasing amount of food waste and the excessive use of mineral fertilizers have caused detrimental impacts on soil, water, and air quality. Though digestate derived from food waste has been reported to partially replace fertilizer, its efficiency requires further improvement. In this study, the effects of digestate-encapsulated biochar were comprehensively investigated based on growth of an ornamental plant, soil characteristics, nutrient leaching and soil microbiome. Results showed that except for biochar, the tested fertilizers and soil additives, i.e., digestate, compost, commercial fertilizer, digestate-encapsulated biochar had positive effects on plants. Especially, the digestate-encapsulated biochar had the best effectiveness as evidenced by 9-25% increase in chlorophyll content index, fresh weight, leaf area and blossom frequency. For the effects of fertilizers or soil additives on soil characteristics and nutrient retention, the digestate-encapsulated biochar leached least N-nutrients (<8%), while the compost, digestate and mineral fertilizer leached up to 25% N-nutrients. All the treatments had minimal effects on the soil properties of pH and electrical conductivity. According to the microbial analysis, the digestate-encapsulated biochar has the comparable role with compost in improving the soil immune system against pathogen infection. The metagenomics coupling with qPCR analysis suggested that digestate-encapsulated biochar boosted the nitrification process and inhibited the denitrification process. This study provides an extensive understanding into the impacts of the digestate-encapsulated biochar on an ornamental plant and offers practical implications for the choice of sustainable fertilizers or soil additives and food-waste digestate management.
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Microbiota , Eliminación de Residuos , Suelo/química , Fertilizantes/análisis , Alimentos , Nitrógeno/análisis , Carbón Orgánico/química , MineralesRESUMEN
The tumor microenvironment (TME), controlled by intrinsic mechanisms of carcinogenesis and epigenetic modifications, has, in recent years, become a heavily researched topic. The TME can be described in terms of hypoxia, metabolic dysregulation, immune escape, and chronic inflammation. RNA methylation, an epigenetic modification, has recently been found to have a pivotal role in shaping the TME. The N6-methylation of adenosine (m6A) modification is the most common type of RNA methylation that occurs in the N6-position of adenosine, which is the primary internal modification of eukaryotic mRNA. Compelling evidence has demonstrated that m6A regulates transcriptional and protein expression through splicing, translation, degradation, and export, thereby mediating the biological processes of cancer cells and/or stromal cells and characterizing the TME. The TME also has a crucial role in the complicated regulatory network of m6A modifications and, subsequently, influences tumor initiation, progression, and therapy responses. In this review, we describe the features of the TME and how the m6A modification modulates and interacts with it. We also focus on various factors and pathways involved in m6A methylation. Finally, we discuss potential therapeutic strategies and prognostic biomarkers with respect to the TME and m6A modification.
Asunto(s)
Adenosina/análogos & derivados , Biomarcadores de Tumor/metabolismo , Neoplasias/metabolismo , Adenosina/metabolismo , Progresión de la Enfermedad , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias/genética , Microambiente TumoralRESUMEN
Flexible sensing can disruptively change the physical form of traditional electronic devices to achieve flexibility in information acquisition, processing, transmission, display, and even energy, and it is a core technology for a new generation of the industrial internet. Fabric is naturally flexible and stretchable, and its knitted ability makes it flexibility and stretchability even more adjustable. However, fabric needs to be electrically conductive to be used for flexible sensing, which allows it to carry a variety of circuits. The dip-coating technique is a common method for preparing conductive fabrics, which are made conductive by attaching conductive fillers to the fabrics. However, the adhesion of the conductive fillers on the surface of such conductive fabrics is weak, and the conductive property will decay rapidly because the conductive filler falls off after repeated stretching, limiting the lifespan of flexible electronic devices based on conductive fabric. We chose multifunctional nanosilver as a conductive filler, and we increased the adhesion of nanosilver to fabric fiber by making nanosilver grow in situ and cover the fiber, so as to obtain conductive fabric with good conductivity. This conductive fabric has a minimum square resistance of 9 Ω/sq and has better electrical conductivity and more stable electrical properties than the conductive fabric prepared using the dip-coating process, and its square resistance did not increase significantlyafter 60 stretches.
Asunto(s)
Electrónica , Textiles , Electrodos , Conductividad EléctricaRESUMEN
The aim of this study was to investigate the harmful effects of acute hypoxia on mouse cerebral cortex and hippocampus and the underlying mechanism. Mouse model of acute hypoxia was constructed by using a sealed glass jar. Laser speckle contrast imaging was used to detect the changes of cerebral blood flow after different time duration of hypoxia. Total superoxide dismutase (T-SOD) and malondialdehyde (MDA) assay kits were used to detect oxidative stress in cerebral cortex and hippocampus. Immunofluorescent staining was used to detect neuroinflammatory response of microglia in the cerebral cortex and hippocampus. One-step TUNEL method was used to detect neuronal apoptosis. The results showed that, compared with non-hypoxia (0 min hypoxia) group, 30 min hypoxia group exhibited decreased cerebral blood flow, higher percentage of CD68+/Iba1+ microglia, and increased neural apoptosis in the cerebral cortex and hippocampus. Compared with 30 min group, 60 min hypoxia group showed significantly decreased cerebral blood flow, increased MDA content in the cortex, as well as greater percentage of CD68+/Iba1+ microglia and neuronal apoptosis in the cerebral cortex and hippocampus. These results suggest that acute hypoxia damages brain tissue in a time-dependent manner and the oxidative stress and neuroinflammation are important mechanisms.