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1.
Plant Physiol ; 191(2): 1017-1035, 2023 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-36417282

RESUMEN

The fast growth of Moso bamboo (Phyllostachys edulis) shoots is caused by the rapid elongation of each internode. However, the key underlying cellular processes and epigenetic mechanisms remain largely unexplored. We used microscopy and multi-omics approaches to investigate two regions (bottom and middle) of the 18th internode from shoots of two different heights (2 and 4 m). We observed that internode cells become longer, and that lignin biosynthesis and glycosyltransferase family 43 (GT43) genes are substantially upregulated with shoot height. Nanopore direct RNA sequencing (DRS) revealed a higher N6-methyladenine (m6A) modification rate in 2-m shoots than in 4-m shoots. In addition, different specific m6A modification sites were enriched at different growth stages. Global DNA methylation profiling indicated that DNA methylation levels are higher in 4-m shoots than in 2-m shoots. We also detected shorter poly(A) tail lengths (PALs) in 4-m shoots compared with 2-m shoots. Genes showing differential PAL were mainly enriched in the functional terms of protein translation and vesicle fusion. An association analysis between PALs and DNA methylation strongly suggested that gene body CG methylation levels are positively associated with PAL. This study provides valuable information to better understand post-transcriptional regulations responsible for fast-growing shoots in Moso bamboo.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Poaceae , Brotes de la Planta/metabolismo , Poaceae/genética , ARN/metabolismo , Epigénesis Genética
2.
Opt Express ; 32(7): 12620-12635, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571080

RESUMEN

A method based on deflectometry to measure the refractive index distribution of radial gradient refractive index (GRIN) lens is proposed in this paper. The method establishes the relationship between the refractive index distribution and the direction of light ray by deriving the propagation equation of light in a non-uniform medium. By measuring the deflection angle using the principle of deflectometry and the assumption of central refraction, the refractive index distribution of the radial GRIN lens is determined. The specific principle of refractive index measurement deflectometry (RIMD) is described in detail, and the correctness and accuracy of the method are verified through numerical simulations. Furthermore, the effects of calibration error, lens surface shape on the accuracy of the measurement results are analyzed. In the experimental section, the proposed method is applied to measure a radial GRIN lens, and the results are compared with the nominal parameters in terms of shape distribution and numerical values, demonstrating good consistency. The measurement error is controlled within the order of 10-3. This method enables rapid and convenient acquisition of full-field information of GRIN lens and holds promising potential for playing an important role in lens manufacturing and production.

3.
Opt Lett ; 49(8): 2129-2132, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38621093

RESUMEN

This Letter presents the frequency-domain searching algorithm in deflectometry (FSAD). By encoding specialized multi-frequency fringe patterns and employing a correlation searching algorithm, the limitations of existing frequency-domain methods can be overcome to some extent, thereby separating front and back surface reflections to obtain complete measurement data. The principles of FSAD are described in detail. In the experiment, a piece of window glass with thickness of 10 mm and a square area of 96 × 96 mm is measured to verify the proposed method.

4.
Nanotechnology ; 35(18)2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38358678

RESUMEN

Graphene is broadly applied as sensitive sensing material results from its superb features. Concurrently, as a derivative of graphene with 0D structure, graphene quantum dots (GQDs) offer more possibilities as a supportive sensing material due to its adjustable size and functional group modification. In this work, GQDs are introduced to single-layer graphene (SLG) based humidity sensor to enhance the sensing performance. Specifically, consistent resistance response to relative humidity (RH) is extended from the range of 10%-60% to 10%-90% by contrary to original SLG based sensor. Parallelly, effect of the amount of GQDs is investigated by means of multiple GQDs deposition. As the resultant higher binding efficiency between water molecules and the functional groups of GQDs, improved response rate is observed. For the case of 4-time deposition of GQDs, the response rate (ΔR/R) reaches ∼130% in RH range of 10%-90%. Besides, the response time and recovery time are ∼0.7 s and ∼1.1 s, respectively. The fluctuation of the resistance change of the sensor under constant humidity is less than 5% over a month which demonstrates long-term reliability.

5.
J Nat Prod ; 87(4): 705-712, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38547118

RESUMEN

Penicilloneines A (1) and B (2) are the first reported quinolone-citrinin hybrids. They were isolated from the starfish-derived fungus Penicillium sp. GGF16-1-2, and their structures were elucidated using spectroscopic, chemical, computational, and single-crystal X-ray diffraction methods. Penicilloneines A (1) and B (2) share a common 4-hydroxy-1-methyl-2(1H)-quinolone unit; however, they differ in terms of citrinin moieties, and these two units are linked via a methylene bridge. Penicilloneines A (1) and B (2) exhibited antifungal activities against Colletotrichum gloeosporioides, with lethal concentration 50 values of 0.02 and 1.51 µg/mL, respectively. A mechanistic study revealed that 1 could inhibit cell growth and promote cell vacuolization and consequent disruption of the fungal cell walls via upregulating nutrient-related hydrolase genes, including putative hydrolase, acetylcholinesterase, glycosyl hydrolase, leucine aminopeptidase, lipase, and beta-galactosidase, and downregulating their synthase genes 3-carboxymuconate cyclase, pyruvate decarboxylase, phosphoketolase, and oxalate decarboxylase.


Asunto(s)
Antifúngicos , Citrinina , Colletotrichum , Penicillium , Quinolonas , Penicillium/química , Colletotrichum/efectos de los fármacos , Quinolonas/farmacología , Quinolonas/química , Quinolonas/aislamiento & purificación , Estructura Molecular , Animales , Citrinina/farmacología , Citrinina/química , Citrinina/aislamiento & purificación , Antifúngicos/farmacología , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Pruebas de Sensibilidad Microbiana
6.
Skeletal Radiol ; 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38880791

RESUMEN

OBJECTIVE: To assess the accuracy of an artificial intelligence (AI) software (BoneMetrics, Gleamer) in performing automated measurements on weight-bearing forefoot and lateral foot radiographs. METHODS: Consecutive forefoot and lateral foot radiographs were retrospectively collected from three imaging institutions. Two senior musculoskeletal radiologists independently annotated key points to measure the hallux valgus, first-second metatarsal, and first-fifth metatarsal angles on forefoot radiographs and the talus-first metatarsal, medial arch, and calcaneus inclination angles on lateral foot radiographs. The ground truth was defined as the mean of their measurements. Statistical analysis included mean absolute error (MAE), bias assessed with Bland-Altman analysis between the ground truth and AI prediction, and intraclass coefficient (ICC) between the manual ratings. RESULTS: Eighty forefoot radiographs were included (53 ± 17 years, 50 women), and 26 were excluded. Ninety-seven lateral foot radiographs were included (51 ± 20 years, 46 women), and 21 were excluded. MAE for the hallux valgus, first-second metatarsal, and first-fifth metatarsal angles on forefoot radiographs were respectively 1.2° (95% CI [1; 1.4], bias = - 0.04°, ICC = 0.98), 0.7° (95% CI [0.6; 0.9], bias = - 0.19°, ICC = 0.91) and 0.9° (95% CI [0.7; 1.1], bias = 0.44°, ICC = 0.96). MAE for the talus-first, medial arch, and calcaneal inclination angles on the lateral foot radiographs were respectively 3.9° (95% CI [3.4; 4.5], bias = 0.61° ICC = 0.88), 1.5° (95% CI [1.2; 1.8], bias = - 0.18°, ICC = 0.95) and 1° (95% CI [0.8; 1.2], bias = 0.74°, ICC = 0.99). Bias and MAE between the ground truth and the AI prediction were low across all measurements. ICC between the two manual ratings was excellent, except for the talus-first metatarsal angle. CONCLUSION: AI demonstrated potential for accurate and automated measurements on weight-bearing forefoot and lateral foot radiographs.

7.
Molecules ; 29(8)2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38675654

RESUMEN

Diabetic wound healing is a significant clinical challenge because abnormal immune cells in the wound cause chronic inflammation and impair tissue regeneration. Therefore, regulating the behavior and function of macrophages may be conducive to improving treatment outcomes in diabetic wounds. Herein, sulfated chitosan (26SCS)-containing composite sponges (26SCS-SilMA/Col-330) with well-arranged layers and high porosity were constructed based on collagen and silk fibroin, aiming to induce an appropriate inflammatory response and promote angiogenesis. The results indicated that the ordered topological structure of composite sponges could trigger the pro-inflammatory response of Mφs in the early stage, and rapid release of 26SCS in the early and middle stages (within the concentration range of 1-3 mg/mL) induced a positive inflammatory response; initiated the pro-inflammatory reaction of Mφs within 3 days; shifted M1 Mφs to the M2 phenotype within 3-7 days; and significantly up-regulated the expression of two typical angiogenic growth factors, namely VEGF and PDGF-BB, on day 7, leading to rapid HUVEC migration and angiogenesis. In vivo data also demonstrated that on the 14th day after surgery, the 26SCS-SilMA/Col-330-implanted areas exhibited less inflammation, faster re-epithelialization, more abundant collagen deposition and a greater number of blood vessels in the skin tissue. The composite sponges with higher 26SCS contents (the (5.0) 26SCS-SilMA/Col-330 and the (7.5) 26SCS-SilMA/Col-330) could better orchestrate the phenotype and function of Mφs and facilitate wound healing. These findings highlight that the 26SCS-SilMA/Col-330 sponges developed in this work might have great potential as a novel dressing for the treatment of diabetic wounds.


Asunto(s)
Quitosano , Inflamación , Macrófagos , Neovascularización Fisiológica , Cicatrización de Heridas , Cicatrización de Heridas/efectos de los fármacos , Quitosano/química , Animales , Humanos , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Neovascularización Fisiológica/efectos de los fármacos , Inflamación/tratamiento farmacológico , Inflamación/patología , Células Endoteliales de la Vena Umbilical Humana , Colágeno/metabolismo , Colágeno/química , Diabetes Mellitus Experimental , Ratones , Ratas , Masculino , Fibroínas/química , Fibroínas/farmacología , Angiogénesis
8.
Small ; 19(38): e2301749, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37211704

RESUMEN

Low infiltration of cytotoxic T lymphocytes and their exhaustion manifest the two concurrent main hurdles for achieving effective tumor immunotherapy of triple-negative breast cancer. It is found that Galectin-9 blockage can revise the exhaustion of effector T cells, meanwhile the repolarization of protumoral M2 tumor-associated macrophages (TAMs) into tumoricidal M1-like ones can recruit effector T cells infiltrating into tumor to boost immune responses. Herein, a sheddable PEG-decorated and M2-TAMs targeted nanodrug incorporating Signal Transducer and Activator of Transcription 6 inhibitor (AS) and anti-Galectin-9 antibody (aG-9) is prepared. The nanodrug responds to acidic tumor microenvironment (TME) with the shedding of PEG corona and the release of aG-9, exerting local blockade of PD-1/Galectin-9/TIM-3 interaction to augment effector T cells via exhaustion reversing. Synchronously, targeted repolarization of M2-TAMs into M1 phenotype by AS-loaded nanodrug is achieved, which promotes tumor infiltration of effector T cells and thus synergizes with aG-9 blockade to boost the therapeutic efficacy. Besides, the PEG-sheddable approach endows nanodrug with stealth ability to reduce immune-related adverse effects caused by AS and aG-9. This PEG sheddable nanodrug holds the potential to reverse the immunosuppressive TME and increase effector T cell infiltration, which dramatically enhances immunotherapy in highly malignant breast cancer.


Asunto(s)
Neoplasias de la Mama , Nanopartículas , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Microambiente Tumoral , Macrófagos , Inmunoterapia , Nanopartículas/uso terapéutico , Línea Celular Tumoral
9.
Opt Lett ; 48(7): 1714-1717, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37221748

RESUMEN

A method for the quantitative measurement of two-dimensional density field distributions based on deflectometry is proposed. With this method, from the point of view of the inverse Hartmann test, the light rays emitted from the camera reach the screen after being disturbed by the shock-wave flow field. After the coordinates of the point source are obtained by using the phase information, the deflection angle of the light ray can be calculated, and then the distribution of the density field can be determined. The principle of density field measurement deflectometry (DFMD) is described in detail. In the experiment, the density fields in wedge-shaped models with three different wedge angles are measured in supersonic wind tunnels, the experimental results from the proposed method are compared with the theoretical results, and the measurement error is found to be around 2.76 × 10-3kg/m3. This method has the advantages of fast measurement, a simple device, and low cost. It provides a new approach, to the best of our knowledge, to measuring the density field of a shock-wave flow field.

10.
Respir Res ; 24(1): 313, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38098080

RESUMEN

BACKGROUND: Sporadic studies have examined the impact of OSA on ACS patients by homocysteine (Hcy) level. This study attempted to comprehensively evaluate the effects of the interaction between Hcy and OSA on long-term cardiovascular outcomes in ACS patients. METHODS: In this prospective, large-scale cohort study, 2160 patients admitted for ACS were recruited to undergo overnight sleep monitoring. OSA was diagnosed when apnea-hypopnea index ≥ 15 events/h. Patients with normohomocysteinemia (NHcy) were defined as having serum Hcy ≤ 15 µmol/L, and the others had hyperhomocysteinemia (HHcy). The primary endpoint was major adverse cerebrocardiovascular event (MACCE), a composite of cardiovascular death, myocardial infarction, stroke, ischemia-driven revascularization and hospitalization for unstable angina and heart failure. RESULTS: A total of 1553 eligible ACS patients (average age: 56.3 ± 10.5 years) were enrolled, among which 819 (52.7%) had OSA, and 988 (63.6%) were with NHcy. OSA did not significantly affect the level of Hcy. During a median follow-up of 2.9 (1.6, 3.5) years, after adjustment for clinical confounders, OSA was associated with increased risk for MACCE occurrence versus non-OSA ones in ACS patients with NHcy (adjusted hazard ratio [HR] = 1.36, 95% confidence interval [CI] 1.02-1.83, P = 0.039), but not in those with HHcy (adjusted HR = 0.92, 95%CI 0.62-1.36, P = 0.668). There was an absence of interaction between homocysteine level and OSA in relation to MACCE (interaction P = 0.106). CONCLUSIONS: OSA was independently associated with worse prognosis in ACS patients with NHcy. Our study emphasized the necessity to identify potential presence of OSA in such a population. TRIAL REGISTRATION: ClinicalTrials.gov; Number: NCT03362385; URL: www. CLINICALTRIALS: gov .


Asunto(s)
Síndrome Coronario Agudo , Apnea Obstructiva del Sueño , Humanos , Persona de Mediana Edad , Anciano , Pronóstico , Síndrome Coronario Agudo/diagnóstico , Síndrome Coronario Agudo/epidemiología , Estudios Prospectivos , Estudios de Cohortes , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/epidemiología , Apnea Obstructiva del Sueño/complicaciones , Homocisteína , Factores de Riesgo
11.
J Sleep Res ; 32(5): e13898, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37020157

RESUMEN

The clinical outcome of obstructive sleep apnea in patients with acute coronary syndrome in relation to hyperuricemia is still unclear. We aimed to explore the clinical prognosis of obstructive sleep apnea in patients with acute coronary syndrome in relation to hyperuricemia status. This was a prospective cohort study. We included consecutively eligible patients with acute coronary syndrome who underwent cardiorespiratory polygraphy between June 2015 and January 2020. According to apnea-hypopnea index ≥ 15 events per hr and serum uric acid level, the population was divided into four groups: hyperuricemia with obstructive sleep apnea; hyperuricemia with non-obstructive sleep apnea; no hyperuricemia with obstructive sleep apnea; and no hyperuricemia with non-obstructive sleep apnea. The primary endpoint was major adverse cardiovascular and cerebrovascular events, including cardiovascular death, myocardial infarction, stroke, ischaemia-driven revascularization, and readmission for unstable angina or heart failure. Spearman correlation analysis and Cox regression model were mainly used to estimate the data. The median follow-up was 2.9 years. Among 1925 patients with acute coronary syndrome, 29.6% had hyperuricemia and 52.6% had obstructive sleep apnea. Uric acid was negatively correlated with minimum arterial oxygen saturation and mean arterial oxygen saturation, and positively correlated with apnea-hypopnea index, oxygen desaturation index and the duration of time with arterial oxygen saturation < 90% (p < 0.001). During 2.9 (1.5, 3.6) years of follow-up, obstructive sleep apnea was associated with an increased risk of major adverse cardiovascular and cerebrovascular events in patients with hyperuricemia (23.5% versus 13.4%; adjusted hazard ratio: 1.834; 95% confidence interval: 1.192-2.821, p = 0.006), but not in patients without hyperuricemia (21.9% versus 19.2%; adjusted hazard ratio: 1.131; 95% confidence interval: 0.880-1.453, p = 0.336). There was a correlation between uric acid levels and sleep respiratory indicators. Obstructive sleep apnea was associated with increased risk of major adverse cardiovascular and cerebrovascular events in patients with acute coronary syndrome with hyperuricemia, but not in patients without hyperuricemia.


Asunto(s)
Síndrome Coronario Agudo , Apnea Obstructiva del Sueño , Humanos , Síndrome Coronario Agudo/complicaciones , Síndrome Coronario Agudo/epidemiología , Ácido Úrico , Estudios Prospectivos , Factores de Riesgo , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/epidemiología
12.
Atmos Environ (1994) ; 308: 119864, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37250918

RESUMEN

The COVID-19 pandemic promoted strict restrictions to human activities in China, which led to an unexpected increase in ozone (O3) regarding to nitrogen oxides (NOx) and volatile organic compounds (VOCs) co-abatement in urban China. However, providing a quantitative assessment of the photochemistry that leads to O3 increase is still challenging. Here, we evaluated changes in O3 arising from photochemical production with precursors (NOX and VOCS) in industrial regions in Shanghai during the COVID-19 lockdowns by using machine learning models and box models. The changes of air pollutants (O3, NOX, VOCs) during the COVID-19 lockdowns were analyzed by deweathering and detrending machine learning models with regard to meteorological and emission effects. After accounting for effects of meteorological variability, we find increase in O3 concentration (49.5%). Except for meteorological effects, model results of detrending the business-as-usual changes indicate much smaller reduction (-0.6%), highlighting the O3 increase attributable to complex photochemistry mechanism and the upward trends of O3 due to clear air policy in Shanghai. We then used box models to assess the photochemistry mechanism and identify key factors that control O3 production during lockdowns. It was found that empirical evidence for a link between efficient radical propagation and the optimized O3 production efficiency of NOX under the VOC-limited conditions. Simulations with box models also indicate that priority should be given to controlling industrial emissions and vehicle exhaust while the VOCs and NOX should be managed at a proper ratio in order to control O3 in winter. While lockdown is not a condition that could ever be continued indefinitely, findings of this study offer theoretical support for formulating refined O3 management in industrial regions in Shanghai, especially in winter.

13.
Mar Drugs ; 21(3)2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36976188

RESUMEN

To investigate the effects of bonito oligopeptide SEP-3 on the repair of liver damage and regulation of liver biorhythm in sleep-deprived mice (SDM), C57BL/6 male mice were subjected to sleep deprivation by modified multi-platform water environment method, and were given different doses of bonito oligopeptide SEP-3 in groups. To determine the liver organ index, liver tissue-related apoptotic protein levels, Wnt/ß-Catenin pathway-related protein expression levels, serum alanine transaminase (ALT), glutamicum transaminase (AST), glucocorticoid (GC), and adrenocorticotropin (ACTH) content in each group of mice, four time points were selected to examine the mRNA expression levels of circadian clock-related genes in mouse liver tissue. The results showed that low, medium, and high doses of SEP-3 significantly increased SDM, ALT, and AST (p < 0.05), and medium and high doses of SEP-3 significantly reduced SDM liver index and GC and ACTH. As SEP-3 increased the apoptotic protein and Wnt/ß-Catenin pathway, mRNA expression gradually tended to normal (p < 0.05). This suggests that sleep deprivation can cause excessive oxidative stress in mice, which can lead to liver damage. Additionally, oligopeptide SEP-3 achieves the repair of liver damage by inhibiting SDM hepatocyte apoptosis, activating liver Wnt/ß-Catenin pathway, and promoting hepatocyte proliferation and migration, and suggests that oligopeptide SEP-3 is closely related to repair of liver damage by regulating the biological rhythm of SDM disorder.


Asunto(s)
Privación de Sueño , beta Catenina , Ratones , Masculino , Animales , beta Catenina/metabolismo , Privación de Sueño/complicaciones , Privación de Sueño/metabolismo , Ratones Endogámicos C57BL , Hígado , Apoptosis , Estrés Oxidativo , Oligopéptidos/farmacología , Oligopéptidos/metabolismo , ARN Mensajero/metabolismo
14.
Chem Biodivers ; 20(6): e202300301, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37097072

RESUMEN

Two new indole diketopiperazine alkaloids (IDAs), (+)19-epi-sclerotiamide (1) and (-)19-epi-sclerotiamide (2), along with 13 known analogs (3-15), were isolated from a soft coral-associated epiphytic fungus Aspergillus versicolor CGF 9-1-2. The structures of two new compounds were established based on the combination of HR-ESI-MS, 1D and 2D NMR spectroscopy, optical rotation measurements and quantum chemical 13 C-NMR, the absolute configurations were determined by experimental and electronic circular dichroism (ECD) calculations. The results of molecular docking showed that all the compounds had a good binding with TDP1, TDP2, TOP1, TOP2, Ache, NLRP3, EGFR, EGFR L858R, EGFR T790M and EGFR T790/L858. Biological evaluation of compounds 3, 6, 8, 11 showed that 3 exerted a strong inhibitory effect on TDP2 with a rate of 81.72 %.


Asunto(s)
Agaricales , Antozoos , Neoplasias Pulmonares , Animales , Dicetopiperazinas/farmacología , Dicetopiperazinas/química , Simulación del Acoplamiento Molecular , Receptores ErbB/metabolismo , Mutación , Inhibidores de Proteínas Quinasas/metabolismo , Aspergillus/química , Alcaloides Indólicos/química , Antozoos/metabolismo , Estructura Molecular
15.
Zhongguo Zhong Yao Za Zhi ; 48(9): 2480-2489, 2023 May.
Artículo en Zh | MEDLINE | ID: mdl-37282877

RESUMEN

Qualitative and quantitative analysis of 2-(2-phenylethyl) chromones in sodium chloride(NaCl)-treated suspension cells of Aquilaria sinensis was conducted by UPLC-Q-Exactive-MS and UPLC-QQQ-MS/MS. Both analyses were performed on a Waters T3 column(2.1 mm×50 mm, 1.8 µm) with 0.1% formic acid aqueous solution(A)-acetonitrile(B) as mobile phases at gradient elution. MS data were collected by electrospray ionization in positive ion mode. Forty-seven phenylethylchromones was identified from NaCl-treated suspension cell samples of A. sinensis using UPLC-Q-Exactive-MS, including 22 flindersia-type 2-(2-phenylethyl) chromones and their glycosides, 10 5,6,7,8-tetrahydro-2-(2-phenylethyl) chromones and 15 mono-epoxy or diepoxy-5,6,7,8-tetrahydro-2-(2-phenylethyl) chromones. Additionally, 25 phenylethylchromones were quantitated by UPLC-QQQ-MS/MS. Overall, the rapid and efficient qualitative and quantitative analysis of phenylethylchromones in NaCl-treated suspension cells of A. sinensis by two LC-MS techniques, provides an important reference for the yield of phenylethylchromones in Aquilariae Lignum Resinatum using in vitro culture and other biotechnologies.


Asunto(s)
Cromonas , Thymelaeaceae , Cloruro de Sodio , Cromatografía Liquida , Flavonoides , Espectrometría de Masas en Tándem
16.
Ann Bot ; 129(1): 53-64, 2022 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-34582551

RESUMEN

BACKGROUND AND AIMS: Soil phosphorus (P) deficiency and salinity are constraints to crop productivity in arid and semiarid regions. Salinity may weaken the effect of P fertilization on plant growth. We investigated the interactive effects of soil P availability and salinity on plant growth, P nutrition and salt tolerance of two alfalfa (Medicago sativa) cultivars. METHODS: A pot experiment was carried out to grow two cultivars of alfalfa in a loess soil under a combination of different rates of added P (0, 40, 80 and 160 mg P kg-1 soil as monopotassium phosphate) and sodium chloride (0, 0.4, 0.8 and 1.6 g NaCl kg-1 soil). Plant biomass, concentrations of P ([P]), sodium ([Na]) and potassium ([K]) were determined, and rhizosheath carboxylates were analysed. KEY RESULTS: There were significant interactions between soil P availability and salinity on some, but not all, of the parameters investigated, and interactions depended on cultivar. Plant growth and P uptake were enhanced by P fertilization, but inhibited by increased levels of salinity. Increasing the salinity resulted in decreased plant P-uptake efficiency and [K]/[Na]. Only soil P availability had a significant effect on the amount of tartrate in the rhizosheath of both cultivars. CONCLUSIONS: Increased salinity aggravated P deficiency. Appropriate application of P fertilizers improved the salt tolerance of alfalfa and increased its productivity in saline soils.


Asunto(s)
Medicago sativa , Salinidad , Fertilización , Fósforo , Raíces de Plantas , Sodio , Suelo , Tartratos/farmacología
17.
Org Biomol Chem ; 20(28): 5535-5542, 2022 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-35788620

RESUMEN

Prenyltransferases (PTs) play important roles in the biosynthesis and structural diversification of natural products. In the present study, two new PTs were characterized from a medicinal plant Murraya exotica. MePT1 unprecedentedly catalyses the formation of two C-geranylated products 8/6-C-geranylumbelliferone together with a trace product 7-O-geranylumbelliferone from umbelliferone. MePT2 regio-specifically catalyses the formation of C-3 dimethylallylated products from quinolone alkaloids. This is the first report that a plant PT catalyses the simultaneous formation of C- and O-prenylated products, and a plant PT specifically utilizes quinolone alkaloids as prenyl acceptors. The results not only provide important insight into the functional diversity of plant PTs and the biosynthesis of the prenylated coumarins, quinolone and carbazole alkaloids in Murraya plants, but also pave the way for the overproduction of the prenylated coumarins and alkaloids using metabolic engineering approaches.


Asunto(s)
Alcaloides , Dimetilaliltranstransferasa , Murraya , Quinolonas , Cumarinas/química , Dimetilaliltranstransferasa/metabolismo , Murraya/química , Murraya/metabolismo
18.
Anal Chem ; 93(29): 10301-10309, 2021 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-34269562

RESUMEN

It is of great significance to disclose the diverse aging pathways for polymers under multiple factors, so as to predict and control the potential aging evolution. However, the current methods fail to distinguish multiple pathways (multi-paths) of polymer aging due to the lack of spatiotemporal resolution. In this work, using polyimide as a model polymer, the hydroxyl, carboxyl, and amino groups from the polyimide aging process were labeled using specific fluorescent probes through boron-oxygen, imine, and thiourea linkages, respectively. When the excitation and emission wavelengths of each fluorescent probe were controlled, the multi-paths in polyimide aging can be visualized individually and simultaneously in three-dimensional fluorescent images. The overall aging process under hydrothermal treatment was destructured into the pyrolysis and hydrolysis pathways. Three-dimensional dynamic studies discovered that the increased humidity, along with the decreased oxygen content, could hamper the pyrolysis reaction and accelerate the hydrolysis reaction, leading to severe degradation of the overall polyimide aging. More importantly, the oxygen showed a higher regulation coefficient in accelerating the pyrolysis reaction, than the water vapor in motivating the hydrolysis reactions. Such a multidimensional identification methodology is able to guide the long-term use of polymers and control their aging process to a harmless direction in advance by tuning the contents of oxygen and water vapor.


Asunto(s)
Colorantes Fluorescentes , Polímeros , Hidrólisis , Oxígeno , Pirólisis
19.
Radiology ; 300(1): 120-129, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33944629

RESUMEN

Background The interpretation of radiographs suffers from an ever-increasing workload in emergency and radiology departments, while missed fractures represent up to 80% of diagnostic errors in the emergency department. Purpose To assess the performance of an artificial intelligence (AI) system designed to aid radiologists and emergency physicians in the detection and localization of appendicular skeletal fractures. Materials and Methods The AI system was previously trained on 60 170 radiographs obtained in patients with trauma. The radiographs were randomly split into 70% training, 10% validation, and 20% test sets. Between 2016 and 2018, 600 adult patients in whom multiview radiographs had been obtained after a recent trauma, with or without one or more fractures of shoulder, arm, hand, pelvis, leg, and foot, were retrospectively included from 17 French medical centers. Radiographs with quality precluding human interpretation or containing only obvious fractures were excluded. Six radiologists and six emergency physicians were asked to detect and localize fractures with (n = 300) and fractures without (n = 300) the aid of software highlighting boxes around AI-detected fractures. Aided and unaided sensitivity, specificity, and reading times were compared by means of paired Student t tests after averaging of performances of each reader. Results A total of 600 patients (mean age ± standard deviation, 57 years ± 22; 358 women) were included. The AI aid improved the sensitivity of physicians by 8.7% (95% CI: 3.1, 14.2; P = .003 for superiority) and the specificity by 4.1% (95% CI: 0.5, 7.7; P < .001 for noninferiority) and reduced the average number of false-positive fractures per patient by 41.9% (95% CI: 12.8, 61.3; P = .02) in patients without fractures and the mean reading time by 15.0% (95% CI: -30.4, 3.8; P = .12). Finally, stand-alone performance of a newer release of the AI system was greater than that of all unaided readers, including skeletal expert radiologists, with an area under the receiver operating characteristic curve of 0.94 (95% CI: 0.92, 0.96). Conclusion The artificial intelligence aid provided a gain of sensitivity (8.7% increase) and specificity (4.1% increase) without loss of reading speed. © RSNA, 2021 Online supplemental material is available for this article.


Asunto(s)
Inteligencia Artificial , Fracturas Óseas/diagnóstico por imagen , Médicos/estadística & datos numéricos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Radiólogos/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Servicio de Urgencia en Hospital , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto Joven
20.
Opt Express ; 29(15): 22931-22943, 2021 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-34614570

RESUMEN

Recently, cylindrical holographic display technology as a 360-degree display technology has attracted much attention. However, all the studies are based on the field of view (FOV) in the azimuth direction, and the issue of FOV in the vertical direction has never been discussed. In this paper, a new holographic display is proposed to expand the vertical FOV by a conical holographic diffraction model, in which the object plane is the outer cylinder and the observation plane is a part of the cone. In this proposed method, the proposed diffraction model is firstly established by the Rayleigh-Sommerfeld diffraction formula, and then the convolution and FFT are used for a fast diffraction calculation. The correctness and effectiveness of our proposed method are verified by the simulation of Young's interference and the numerical reconstructions from the complex amplitude and encoded holograms, respectively. In addition, an accurate relationship between the conical inclination angle and the vertical FOV expansion is analyzed, and the simulation results show that our proposed method can significantly expand the vertical FOV by 0.4 of the original object. Therefore, the issue of the vertical FOV in cylindrical holography is deeply discussed and successfully addressed for the first time.

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