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1.
Plant J ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38457289

RESUMO

The petals of rose (Rosa sp.) flowers determine the ornamental and industrial worth of this species. The number of petals in roses was previously shown to be subject to fluctuations in ambient temperature. However, the mechanisms by which rose detects and responds to temperature changes are not entirely understood. In this study, we identified short interstitial telomere motifs (telo boxes) in the second intron of AGAMOUS (RcAG) from China rose (Rosa chinensis) that play an essential role in precise temperature perception. The second intron of RcAG harbors two telo boxes that recruit telomere repeat binding factors (RcTRBs), which interact with CURLY LEAF (RcCLF) to compose a repressor complex. We show that this complex suppresses RcAG expression when plants are subjected to low temperatures via depositing H3K27me3 marks (trimethylation of lysine 27 on histone H3) over the RcAG gene body. This regulatory mechanism explains the low-temperature-dependent decrease in RcAG transcript levels, leading to the production of more petals under these conditions. Our results underscore an interesting intron-mediated regulatory mechanism governing RcAG expression, enabling rose plants to perceive temperature cues and establish petal numbers.

2.
Mater Horiz ; 11(7): 1817, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38379526

RESUMO

Correction for 'Solution-processed white OLEDs with power efficiency over 90 lm W-1 by triplet exciton management with a high triplet energy level interfacial exciplex host and a high reverse intersystem crossing rate blue TADF emitter' by Liang Chen et al., Mater. Horiz., 2022, 9, 1299-1308, https://doi.org/10.1039/D1MH02060A.

3.
J Fungi (Basel) ; 10(2)2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38392798

RESUMO

In this study, delta-12 desaturase was overexpressed in Yarrowia lipolytica using the single-copy integrative vector pINA1312 and multicopy integrative vector pINA1292, resulting in the engineered yeast strains 1312-12 and 1292-12, respectively. The content of intracellular linoleic acid (LA) in the 1292-12 strain was much higher than in the 1312-12 strain and the control group. One interesting finding was that the 1292-12 strain showed obvious changes in surface morphology. The 1292-12 colonies were much smaller and smoother, whereas their single cells became much larger compared to the control strain. In addition, the dry cell weight (DCW) of the 1292-12 strain was obviously increased from 8.5 to 12.7 g/L, but the viable cell number sharply decreased from 107 to 105/mL. These results indicated that increased LA content in Yarrowia lipolytica could induce morphological changes or even oxidative stress-dependent cell death. The reactive oxygen species (ROS) and malondialdehyde (MDA) were accumulated in the 1292-12 strain, while the antioxidant activities of intracellular catalase (CAT) and superoxide dismutase (SOD) were significantly decreased by 27.6 and 32.0%, respectively. Furthermore, it was also revealed that these issues could be ameliorated by the exogenous supplementation of vitamin C, fish and colza oil.

4.
Chem Biol Drug Des ; 103(1): e14386, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37923393

RESUMO

Baicalin (BA) is a natural product extract with anti-inflammatory, antioxidant, and hepatoprotective properties. Given that the exact underlying mechanisms responsible for the impact of BA on liver cirrhosis remain ambiguous, a detailed investigation is sorely needed. Accordingly, a rat liver cirrhosis model was established via the intraperitoneal injection of diethyl nitrosamine (DEN, 100 mg/kg). Following the modeling, these rats were given BA (100 mg/kg) or N-acetylcysteine (NAC, 150 mg/kg) alone or in combination. The pathological morphology of rat liver tissues in each group was observed by hematoxylin and eosin staining and Masson's trichrome staining. The expression of fibrosis-related proteins was evaluated by Western blot, and the levels of liver function-related biochemical indexes, oxidative stress-related indexes, and inflammatory factors in the serum by enzyme-linked immunosorbent assays (ELISA). The level of mitochondrial reactive oxygen species was measured by flow cytometry. The results depicted that in the rat model of DEN-induced liver cirrhosis, BA reduced the expression of fibrosis-related proteins (collagen type I alpha 1, α-smooth muscle actin, and transforming growth factor-ß1), thereby alleviating the structural fibrosis of liver tissue. Furthermore, BA could diminish the level of mitochondrial reactive oxygen species, and the serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), malondialdehyde (MDA), interleukin (IL)-1ß, IL-6, tumor necrosis factor-α (TNF-α), and monocyte chemotactic protein-1 (MCP-1), while promoting albumin, superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) levels. Notably, all these effects of BA above were strengthened following the combined treatment of BA and NAC. On the whole, BA suppresses liver fibrosis by inhibiting oxidative stress and inflammation, thereby exerting a hepatoprotective effect.


Assuntos
Flavonoides , Cirrose Hepática , Nitrosaminas , Ratos , Animais , Espécies Reativas de Oxigênio/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Fígado , Estresse Oxidativo , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Nitrosaminas/efeitos adversos , Nitrosaminas/metabolismo
5.
Math Biosci Eng ; 20(8): 14959-14977, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37679167

RESUMO

With the development of the Internet, people have paid more attention to privacy protection, and privacy protection technology is widely used. However, it also breeds the darknet, which has become a tool that criminals can exploit, especially in the fields of economic crime and military intelligence. The darknet detection is becoming increasingly important; however, the darknet traffic is seriously unbalanced. The detection is difficult and the accuracy of the detection methods needs to be improved. To overcome these problems, we first propose a novel learning method. The method is the Chebyshev distance based Between-class learning (CDBC), which can learn the spatial distribution of the darknet dataset, and generate "gap data". The gap data can be adopted to optimize the distribution boundaries of the dataset. Second, a novel darknet traffic detection method is proposed. We test the proposed method on the ISCXTor 2016 dataset and the CIC-Darknet 2020 dataset, and the results show that CDBC can help more than 10 existing methods improve accuracy, even up to 99.99%. Compared with other sampling methods, CDBC can also help the classifiers achieve higher recall.

6.
Angew Chem Int Ed Engl ; 62(47): e202313084, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37775994

RESUMO

The hyperfluorescence has drawn great attention in achieving efficient narrowband emitting devices based on multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters. However, achieving efficient solution-processed pure blue hyperfluorescence devices is still a challenge, due to the unbalanced charge transport and serious exciton quenching caused by that the holes are easily trapped on the high-lying HOMO (the highest occupied molecular orbital) level of traditional diphenylamine-decorated emitters. Here, we developed two narrowband blue organoboron emitters with low-lying HOMO levels by decorating the MR-TADF core with weakly electron-donating carbazoles, which could suppress the hole trapping effect by reducing the hole traps between host and MR-TADF emitter from deep (0.40 eV) to shallow (0.14/0.20 eV) ones for facilitating hole transport and exciton formation, as well as avoiding exciton quenching. And the large dihedral angle between the carbazole and MR-TADF core makes the carbazole act as a steric hindrance to inhibit molecular aggregation. Accordingly, the optimized solution-processed pure blue hyperfluorescence devices simultaneously realize record external quantum efficiency of 29.2 %, narrowband emission with a full-width at half-maximum of 16.6 nm, and pure blue color with CIE coordinates of (0.139, 0.189), which is the best result for the solution-processed organic light-emitting diodes based on MR-TADF emitters.

7.
Comput Math Methods Med ; 2022: 9914927, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36110569

RESUMO

Introduction: Novel coronavirus pneumonia (COVID-19) is an acute respiratory disease caused by the novel coronavirus SARS-CoV-2. Severe and critical illness, especially secondary bacterial infection (SBI) cases, accounts for the vast majority of COVID-19-related deaths. However, the relevant biological indicators of COVID-19 and SBI are still unclear, which significantly limits the timely diagnosis and treatment. Methods: The differentially expressed genes (DEGs) between severe COVID-19 patients with SBI and without SBI were screened through the analysis of GSE168017 and GSE168018 datasets. By performing Gene Ontology (GO) enrichment analysis for significant DEGs, significant biological processes, cellular components, and molecular functions were selected. To understand the high-level functions and utilities of the biological system, the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis was performed. By analyzing protein-protein interaction (PPI) and key subnetworks, the core DEGs were found. Results: 85 DEGs were upregulated, and 436 DEGs were downregulated. The CD14 expression was significantly increased in the SBI group of severe COVID-19 patients (P < 0.01). The area under the curve (AUC) of CD14 in the SBI group in severe COVID-19 patients was 0.9429. The presepsin expression was significantly higher in moderate to severe COVID-19 patients (P < 0.05). Presepsin has a diagnostic value for moderate to severe COVID-19 with the AUC of 0.9732. The presepsin expression of COVID-19 patients in the nonsurvivors was significantly higher than that in the survivors (P < 0.05). Conclusion: Presepsin predicts severity and SBI in COVID-19 and may be associated with prognosis in COVID-19.


Assuntos
Infecções Bacterianas , COVID-19 , Biologia Computacional , Bases de Dados Genéticas , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Receptores de Lipopolissacarídeos/genética , Fragmentos de Peptídeos/genética , SARS-CoV-2 , Transdução de Sinais/genética
8.
J Agric Food Chem ; 70(29): 9073-9083, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35844180

RESUMO

Diacylglycerol acyltransferase (DGAT) catalyzes the binding of acyl-CoA to diacylglycerol to form triacylglycerol (TAG). Previous studies strongly indicate that DGAT2, rather than DGAT1, is crucial for TAG accumulation in the oleaginous fungus Mucor circinelloides. To increase the lipid content of M. circinelloides WJ11, McDGAT2 was overexpressed by homologous recombination; compared to the control strain Mc2075, transformants McDGAT2d showed a significant increase in biomass for both spores and mycelia (from 87.7 to 101.2 mg/g in spores and from 75.6 to 93.1 mg/g in mycelia). McDGAT2 overexpression under static solid fermentation gave a greater boost to lipid accumulation in mycelia than in spores. Total fatty acid content in mycelia increased by 68.0% (from 13.6 to 22.8%) and in spores by 26.3% (from 10.6 to 13.4%). However, under submerged fermentation, the lipid content of McDGAT2d was the same as the control, while biomass was slightly reduced. Transcriptomics showed that NADPH was derived mainly from the pentose phosphate pathway, acetyl-CoA was from multiple pathways, and leucine metabolism played an important role in substrate supply for fatty acid biosynthesis. Static solid fermentation may be the more suitable fermentation method for microbial oil production by filamentous fungi due to its lower fermentation costs.


Assuntos
Diacilglicerol O-Aciltransferase , Metabolismo dos Lipídeos , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Ácidos Graxos/metabolismo , Mucor/química , Triglicerídeos/metabolismo
9.
Biotechnol Lett ; 44(4): 595-604, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35288781

RESUMO

Oxygen availability is a limiting factor for lipid biosynthesis in eukaryotic microorganisms. Two bacterial hemoglobins from Vitreoscilla sp. (VHb) and Shinorhizobium meliloti (SHb), which deliver oxygen to the respiratory chain to produce more ATP, were introduced into Mucor circinelloides to alleviate oxygen limitation, thereby improving cell growth and fatty acid production. The VHb and SHb genes were integrated into the M. circinelloides MU402 genome by homologous recombination. VHb and SHb protein expression was verified by carbon monoxide difference spectrum analysis. The biomass was increased by ~ 50% in the strain expressing SHb compared with VHb. The total fatty acid (TFA) content of the strain expressing SHb reached 15.7% of the dry cell weight (~ 40% higher than that of the control strain) during flask cultivation. The biomass and TFA content were markedly increased (12.1 g/L and 21.1% dry cell weight, respectively) in strains expressing SHb than strains expressing VHb during fermenter cultivation. VHb and SHb expression also increased the proportion of polyunsaturated fatty acids. Overexpressed bacterial hemoglobins, especially SHb, increased cell growth and TFA content in M. circinelloides at low and high aeration, suggesting that SHb improves fatty acid production more effectively than VHb in oleaginous microorganisms.


Assuntos
Metabolismo dos Lipídeos , Mucor , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Ácidos Graxos/metabolismo , Hemoglobinas/metabolismo , Mucor/genética , Mucor/metabolismo , Oxigênio/metabolismo , Hemoglobinas Truncadas/genética , Hemoglobinas Truncadas/metabolismo
10.
Mater Horiz ; 9(4): 1299-1308, 2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35195631

RESUMO

Solution-processed white organic light-emitting diodes (WOLEDs) have shown much lower device efficiency than their vacuum-deposited counterparts, due to the lack of triplet exciton management in a single-emissive-layer device structure, which will induce triplet-triplet annihilation (TTA) and triplet-polaron annihilation (TPA). Here, two kinds of solution-processed WOLEDs, including thermally activated delayed fluorescence (TADF)/phosphorescence hybrid WOLEDs and all-TADF WOLEDs, with high power efficiency are developed by using a high triplet energy level (T1) interfacial exciplex as a host and a high reverse intersystem crossing (RISC) rate TADF emitter as a blue dopant for triplet exciton management. The interfacial exciplex host with high T1 can ensure that triplet excitons transfer from the host to the blue emitter, and the blue TADF emitter with high RISC rate (1.15 × 107 s-1) can rapidly upconvert triplet excitons to singlet ones to avoid TTA and TPA. The solution-processed TADF/phosphorescence hybrid and all-TADF WOLEDs exhibit maximum external quantum efficiencies of 31.1% and 27.3%, together with maximum power efficiencies of 93.5 and 70.4 lm W-1, respectively, which are the record efficiencies for solution-processed WOLEDs, and quite comparable to those of most vacuum-deposited counterparts.

11.
BMC Infect Dis ; 22(1): 59, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35039000

RESUMO

BACKGROUND: In March 2020, the WHO declared the novel coronavirus outbreak a global pandemic. While great success in coronavirus disease 2019 (COVID-19) control has been achieved in China, imported cases have become a major challenge. This study aimed to describe the epidemiological and clinical characteristics of imported COVID-19 cases and to assess the effectiveness of screening strategies in Beijing, China. METHODS: This retrospective study included all imported cases transferred to Beijing Ditan Hospital from 29 February to 20 March 2020 who were screened by both chest computed tomography (CT) and reverse-transcriptase-polymerase chain reaction (RT-PCR) at the initial presentation. Demographic, clinical and laboratory data, in addition to chest CT imaging, were collected and analysed. RESULTS: In total, 2545 cases were included, among which 71 (2.8%) were finally diagnosed with laboratory-confirmed COVID-19. The majority 63 (88.7%) were from Europe. The most common initial symptoms were cough and fever, which accounted for 49.3% and 42.3%, respectively. Only four cases (5.6%) had lymphocytopenia, and thirteen cases (18.3%) demonstrated elevated levels of C-reactive protein (CRP). All cases had normal serum levels of procalcitonin (PCT). At initial presentation, among the 71 confirmed cases, 59 (83.1%) had a positive RT-PCR assay, and 35 (49.3%) had a positive chest CT. Twelve (16.9%) had a negative RT-PCR assay but a positive chest CT. CONCLUSIONS: A combination of RT-PCR and chest CT is an effective strategy for the screening of imported COVID-19 cases. Our findings provide important information and clinical evidence about the infection control of imported COVID-19 cases.


Assuntos
COVID-19 , Pequim/epidemiologia , China/epidemiologia , Humanos , Pandemias , Estudos Retrospectivos , SARS-CoV-2
12.
Medicine (Baltimore) ; 100(34): e26933, 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34449458

RESUMO

ABSTRACT: It is presently unknown whether imported cases of the 2019 coronavirus disease (COVID-19) have different characteristics when compared with local cases. To compare the clinical characteristics of local cases of COVID-19 in China compared with those imported from abroad.This was a retrospective study of confirmed cases of COVID-19 admitted at the Beijing Ditan Fever Emergency Department between February 29th, 2020, and March 27th, 2020. The clinical characteristics of the patients were compared between local and imported cases.Compared with local cases, the imported cases were younger (27.3 ±â€Š11.7 vs. 43.6 ±â€Š22.2 years, P < .001), had a shorter interval from disease onset to admission (1.0 (0.0-2.0) vs 4.0 (2.0-7.0) days, P < .001), lower frequencies of case contact (17.4% vs 94.1%, P < .001), fever (39.1% vs 82.4%, P < .001), cough (33.3% vs 51.0%, P = .03), dyspnea (1.9% vs 11.8%, P = .01), fatigue (7.5% vs. 27.5%, P = 0.001), muscle ache (4.7% vs. 25.5%, P < 0.001), and comorbidities (P < .05). The imported cases were less severe than the local cases, with 40.4% versus 5.9% mild cases, 2.8% versus 15.7% severe cases, and no critical cases (P < .001). The length of hospital stay was longer in imported cases than in local cases (32.3 ±â€Š14.5 vs 21.7 ±â€Š11.2 days, P < .001). The imported cases showed smaller biochemical perturbations than the local cases. More imported cases had no sign of pneumonia at computed tomography (45.0% vs 14.9%, P = .001), and none had pleural effusion (0% vs 14.9%, P < .001).Compared with local cases, the imported cases of COVID-19 presented with milder disease and less extensive symptoms and signs.


Assuntos
COVID-19/epidemiologia , COVID-19/patologia , Adulto , Fatores Etários , Idoso , COVID-19/complicações , China/epidemiologia , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , SARS-CoV-2 , Índice de Gravidade de Doença , Fatores Sexuais , Tempo para o Tratamento
13.
AIDS Res Hum Retroviruses ; 36(9): 753-761, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32580561

RESUMO

Assessment tools are necessary for the adequate stratification of patients with AIDS-related pneumocystis pneumonia (PCP). The aim of this study was to evaluate the ability of severity assessment scores and inflammation- and nutrition-based parameters for predicting the 180-day mortality of AIDS-related PCP. This was a retrospective cohort study of patients with AIDS-related PCP admitted at the Beijing Di-Tan Hospital. The CURB-65 score, Pneumonia Severity Index (PSI) score, Acute Physiology And Chronic Health Evaluation II (APACHE II) score, C-reactive protein-to-albumin ratio (CAR), procalcitonin, neutrophil-to-lymphocyte ratio, lymphocyte-to-monocyte ratio, and platelet-to-lymphocyte ratio during the first 24 h of intensive care unit admission were analyzed. The prognostic values of the severity assessment scores and biomarkers for 180-day mortality were evaluated using receiver operating characteristic (ROC) curves and integrated discrimination improvement (IDI) indexes. A total of 123 patients with AIDS-related PCP were included. Fifty-five patients were dead, and 68 were still alive at 180 days after admission. CAR, CURB-65, PSI, and APACHE II were independent predictors of 180-day mortality. The optimal cutoff value of CAR was 2.0 mg/g [area under the ROC curve = 0.844, 95% credential interval (CI) = 0.776-0.913], and CAR >2.0 mg/g increased the prognostic value of all three severity assessment scores, with an IDI index of 5.1% for the CURB-65 score, 8.1% for the PSI score, and 4.1% for the APACHE II score (all p < .05). Combining CAR >2.0 mg/g enhanced the capability of CURB-65, APACHE II, and PSI in predicting the 180-day mortality of patients with AIDS-related PCP.


Assuntos
Síndrome de Imunodeficiência Adquirida , Infecções por HIV , Pneumonia por Pneumocystis , Proteína C-Reativa , Humanos , Pneumonia por Pneumocystis/diagnóstico , Prognóstico , Curva ROC , Estudos Retrospectivos , Índice de Gravidade de Doença
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