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1.
Pestic Biochem Physiol ; 202: 105933, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38879325

RESUMO

Citrus sour rot is a common postharvest citrus disease caused by Geotrichum citri-aurantiiti, which has led to enormous economic losses, particularly during rainy seasons. In this study, we aimed to clarify the impact of berberine hydrochloride (BH), the hydrochloride form of an isoquinoline alkaloid, on the control efficiency of citrus sour rot and its antifungal mode against G. citri-aurantii. Results demonstrated that BH markedly impede the propagation of G. citri-aurantii by delaying the spores development from dormant stage into swollen and germinating stages, with the MIC and MFC value of 0.08 and 0.16 g L-1, respectively. When the artificially inoculated citrus fruit in control group were totally rotted, the disease incidence of BH-treated groups decreased by 35.00%-73.30%, which effectively delayed the disease progression and almost did not negatively affect fruit quality. SEM observation, CFW and PI staining images revealed that BH caused significant damage to both the cell membrane and cell wall of G. citri-aurantii spores, whereas only the cell membrane of the mycelium was affected. The impact of cell wall was related to the block of chitin and ß-1,3-glucan synthesis. Transcriptome results and further verification proved that 0.5 × MIC BH treatment affected the glycolysis pathway and TCA cycle mainly by inhibiting the production of acetyl-CoA and pyruvate. Subsequently, the activities of key enzymes declined, resulting in a further decrease in ATP levels, ultimately inhibiting the germination of spores. In conlusion, BH delays citrus sour rot mainly by disrupting carbohydrate and energy metabolism of G. citri-aurantii spores.


Assuntos
Berberina , Citrus , Metabolismo Energético , Geotrichum , Doenças das Plantas , Esporos Fúngicos , Citrus/microbiologia , Geotrichum/efeitos dos fármacos , Geotrichum/metabolismo , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Berberina/farmacologia , Metabolismo Energético/efeitos dos fármacos , Esporos Fúngicos/efeitos dos fármacos , Metabolismo dos Carboidratos/efeitos dos fármacos , Fungicidas Industriais/farmacologia
2.
BMC Public Health ; 24(1): 1481, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38831260

RESUMO

BACKGROUND: This hemodialysis center experienced the pandemic from December 2022 to January 2023. Therefore, we sought to describe the clinical characteristics and mortality outcomes in hemodialysis patients during this Omicron surge. METHODS: According to whether they are infected, they are divided into two groups: SARS-CoV-2-positive and SARS-CoV-2-negative. The SARS-CoV-2-positive group was divided into a survival group and a non-survival group for comparison. RESULTS: 366 of 457 hemodialysis patients were infected with SARS-CoV-2. The most common symptoms observed were fever (43.2%) and cough (29.8%), Followed by diarrhea (1.4%). Hemodialysis patients with hypertension were more susceptible to SARS-CoV-2 infection. The lymphocyte count, serum creatinine, serum potassium, and serum phosphorus in the SARS-CoV-2-positive group were significantly lower than those in the SARS-CoV-2-negative group. The all-cause mortality rate for infection with SARS-CoV-2 was 5.2%. Only 7 of 366 SARS-CoV-2-positive patients were admitted to the intensive care unit, but 6 of them died. Intensive care unit hospitalization rates were significantly higher in the non-survival group compared with the survival group. White blood cells count, neutrophil count, C-reactive protein, AST, and D-dimer in the non-survival group were higher than those in the survival group. The lymphocyte count, hemoglobin concentration, serum creatinine, serum albumin, serum phosphorus and parathyroid hormone in the non-survival group were lower than those in the survival group. Age > 65 years, elevated C-reactive protein and AST are independent risk factors for death. Finally, no significant difference in vaccination status was found between the SARS-CoV-2-positive group and the negative group. CONCLUSIONS: Hemodialysis patients are at high risk for SARS-CoV-2 infection. Ensuring the adequacy of hemodialysis treatment and maintaining good physical condition of patients are the top priorities.


Assuntos
COVID-19 , Diálise Renal , SARS-CoV-2 , Humanos , COVID-19/mortalidade , COVID-19/terapia , COVID-19/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Adulto , Falência Renal Crônica/terapia , Falência Renal Crônica/mortalidade , Hospitalização/estatística & dados numéricos
3.
Polymers (Basel) ; 16(11)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38891496

RESUMO

Dielectric elastomer is a kind of electronic electroactive polymer, which plays an important role in the application of soft robots and flexible electronics. In this study, an all-organic polyaniline/copper phthalocyanine/silicone rubber (PANI/CuPc/PDMS) dielectric composite with superior comprehensive properties was prepared by manipulating the arrangement of filler in a polymer matrix assisted by electric fields. Both CuPc particles and PANI particles can form network structures in the PDMS matrix by self-assembly under electric fields, which can enhance the dielectric properties of the composites at low filler content. The dielectric constant of the assembled PANI/CuPc/PDMS composites can reach up to 140 at 100 Hz when the content of CuPc and PANI particles is 4 wt% and 2.5 wt%, respectively. Moreover, the elastic modulus of the composites remains below 2 MPa, which is important for electro-deforming. The strain of assembled PANI/CuPc/PDMS three-phase composites at low electric field strength (2 kV/mm) can increase up to five times the composites with randomly dispersed particles, which makes this composite have potential application in the field of soft robots and flexible electronics.

4.
Plant Divers ; 46(2): 219-228, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38807906

RESUMO

Here, we infer the historical biogeography and evolutionary diversification of the genus Lilium. For this purpose, we used the complete plastomes of 64 currently accepted species in the genus Lilium (14 plastomes were newly sequenced) to recover the phylogenetic backbone of the genus and a time-calibrated phylogenetic framework to estimate biogeographical history scenarios and evolutionary diversification rates of Lilium. Our results suggest that ancient climatic changes and geological tectonic activities jointly shaped the distribution range and drove evolutionary radiation of Lilium, including the Middle Miocene Climate Optimum (MMCO), the late Miocene global cooling, as well as the successive uplift of the Qinghai-Tibet Plateau (QTP) and the strengthening of the monsoon climate in East Asia during the late Miocene and the Pliocene. This case study suggests that the unique geological and climatic events in the Neogene of East Asia, in particular the uplift of QTP and the enhancement of monsoonal climate, may have played an essential role in formation of uneven distribution of plant diversity in the Northern Hemisphere.

5.
Mar Drugs ; 22(5)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38786597

RESUMO

Abnormal melanogenesis can lead to hyperpigmentation. Tyrosinase (TYR), a key rate-limiting enzyme in melanin production, is an important therapeutic target for these disorders. We investigated the TYR inhibitory activity of hydrolysates extracted from the muscle tissue of Takifugu flavidus (TFMH). We used computer-aided virtual screening to identify a novel peptide that potently inhibited melanin synthesis, simulated its binding mode to TYR, and evaluated functional efficacy in vitro and in vivo. TFMH inhibited the diphenolase activities of mTYR, reducing TYR substrate binding activity and effectively inhibiting melanin synthesis. TFMH indirectly reduced cAMP response element-binding protein phosphorylation in vitro by downregulating melanocortin 1 receptor expression, thereby inhibiting expression of the microphthalmia-associated transcription factor, further decreasing TYR, tyrosinase related protein 1, and dopachrome tautomerase expression and ultimately impeding melanin synthesis. In zebrafish, TFMH significantly reduced black spot formation. TFMH (200 µg/mL) decreased zebrafish TYR activity by 43% and melanin content by 52%. Molecular dynamics simulations over 100 ns revealed that the FGFRSP (T-6) peptide stably binds mushroom TYR via hydrogen bonds and ionic interactions. T-6 (400 µmol/L) reduced melanin content in B16F10 melanoma cells by 71% and TYR activity by 79%. In zebrafish, T-6 (200 µmol/L) inhibited melanin production by 64%. TFMH and T-6 exhibit good potential for the development of natural skin-whitening cosmetic products.


Assuntos
Melaninas , Melanoma Experimental , Monofenol Mono-Oxigenase , Takifugu , Peixe-Zebra , Animais , Melaninas/biossíntese , Takifugu/metabolismo , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Camundongos , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/metabolismo , Linhagem Celular Tumoral , Fator de Transcrição Associado à Microftalmia/metabolismo , Músculos/efeitos dos fármacos , Músculos/metabolismo , Oxirredutases Intramoleculares/metabolismo , Receptor Tipo 1 de Melanocortina/metabolismo , Simulação de Dinâmica Molecular , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo
6.
BMC Plant Biol ; 24(1): 277, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38605351

RESUMO

BACKGROUND: The "woody clade" in Saxifragales (WCS), encompassing four woody families (Altingiaceae, Cercidiphyllaceae, Daphniphyllaceae, and Hamamelidaceae), is a phylogenetically recalcitrant node in the angiosperm tree of life, as the interfamilial relationships of the WCS remain contentious. Based on a comprehensive sampling of WCS genera, this study aims to recover a robust maternal backbone phylogeny of the WCS by analyzing plastid genome (plastome) sequence data using Bayesian inference (BI), maximum likelihood (ML), and maximum parsimony (MP) methods, and to explore the possible causes of the phylogenetic recalcitrance with respect to deep relationships within the WCS, in combination with molecular and fossil evidence. RESULTS: Although the four WCS families were identically resolved as monophyletic, the MP analysis recovered different tree topologies for the relationships among Altingiaceae, Cercidiphyllaceae, and Daphniphyllaceae from the ML and BI phylogenies. The fossil-calibrated plastome phylogeny showed that the WCS underwent a rapid divergence of crown groups in the early Cretaceous (between 104.79 and 100.23 Ma), leading to the origin of the stem lineage ancestors of Altingiaceae, Cercidiphyllaceae, Daphniphyllaceae, and Hamamelidaceae within a very short time span (∼4.56 Ma). Compared with the tree topology recovered in a previous study based on nuclear genome data, cytonuclear discordance regarding the interfamilial relationships of the WCS was detected. CONCLUSIONS: Molecular and fossil evidence imply that the early divergence of the WCS might have experienced radiative diversification of crown groups, extensive extinctions at the genus and species levels around the Cretaceous/Paleocene boundary, and ancient hybridization. Such evolutionarily complex events may introduce biases in topological estimations within the WCS due to incomplete lineage sorting, cytonuclear discordance, and long-branch attraction, potentially impacting the accurate reconstruction of deep relationships.


Assuntos
Genomas de Plastídeos , Saxifragales , Humanos , Filogenia , Saxifragales/genética , Fósseis , Teorema de Bayes , Plastídeos/genética
7.
Planta ; 258(2): 23, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37341801

RESUMO

MAIN CONCLUSION: The pistillate flowers of Lithocarpus dealbatus show two pollen tube (PT) arresting sites (the style-joining and micropyle) within the pistil during the postpollination-prezygotic stage. The PT, arrested at the pre-ovule stage, enhanced PT competition allowing the most compatible PTs to enter the ovary to ensure the highest fertilization success. During the shift from animal pollination to wind pollination, plants require a series of changes in reproductive traits. The mode of pollination is striking labile in Fagaceae. Lithocarpus is insect pollinated and is closely related to wind-pollinated Quercus. Little is known about the sexual reproduction of Lithocarpus. This study aimed to reveal the sexual reproduction of Lithocarpus dealbatus and to explore the evolutionary pattern of the key sexual reproduction traits to better understand their possible role in labile pollination. We found that after pollination, L. dealbatus PTs grew slowly in the style reaching style-joining in mid-January of the second year; then PT growth was arrested at style-joining for four months. Only two to three PTs resumed growth in mid-May to reach the micropyle, where PT growth ceased for one month before one PT resumed growth and passed through the micropyle to the embryo sac. Fagaceae showed a generalized mating system. Vast pollen production, small-sized pollen grains, long stigmatic receptive time, and reduced perianth were compatible with beetle pollination syndrome, representing the plesiomorphic status in Fagaceae. A large stigmatic surface and dry pollen grains linked to wind pollination might be independently derived several times in fagaceous lineages. Beetle pollination syndrome can cope with the uncertainty of pollinators to ensure conspecific pollen capture, which represents pre-adaptation status and has a selective advantage when conditions change, favouring wind pollination. The arrest of the PT at style-joining is a unique mechanism in later derived fagaceous lineages to enhance PT competition and promote outcrossing.


Assuntos
Fagaceae , Fagales , Fertilização , Flores , Polinização , Reprodução
8.
Environ Sci Pollut Res Int ; 30(10): 26012-26031, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36350448

RESUMO

Along with the steady worsening of environmental contamination, improving environmental governance performance (EGP) is an urgent issue that needs to be addressed. This study adopts panel data from 275 Chinese cities to examine the holistic relationship between the digital economy (DE) and urban EGP in multiple dimensions. The relationship is tested using fixed-effects models, mediated effects models, panel threshold models, and the spatial Durbin models. Results indicated that (1) the DE can effectively improve urban EGP. The findings still hold after robustness tests using instrumental variable estimation and the introduction of exogenous policy shocks. (2) The analysis of mediating effects shows that green technology innovation and industrial structure optimization are critical transmissions. (3) The panel threshold regression results indicate a nonlinear incremental phenomenon of the significant impact of the DE on urban EGP when nighttime lighting data is used as the threshold. (4) Spatial spillover analysis shows a positive spatial spillover effect of DE development on EGP in the surrounding cities. (5) Spatial heterogeneity analysis states that the enhancement effect of DE development on EGP is more significant in eastern China. Furthermore, areas located within urban agglomerations are more influenced by the DE. These findings provide a policy reference for fully exploiting the environmental enhancement effects of the DE.


Assuntos
Conservação dos Recursos Naturais , Política Ambiental , China , Cidades , Desenvolvimento Econômico
9.
J Org Chem ; 85(12): 7896-7904, 2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32466648

RESUMO

A Pd-catalyzed linear selective intermolecular asymmetric dearomative allylic alkylation reaction of naphthols with alkoxyallenes under mild reaction conditions is reported. The transformation is successfully promoted by Pd2(dba)3 and the chiral Trost ligand and provides a general atom-efficient protocol to obtain various ß-naphthalenones bearing an all carbon quaternary stereogenic center in good yields and chemo- and stereoselectivities.

10.
J Org Chem ; 84(16): 10111-10119, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31343177

RESUMO

An efficient tetrakis(triphenylphosphine)palladium- and Brønsted acid catalyzed allylic substitution reaction of benzothiazolylacetamide with allylic alcohols in water has been developed, and the corresponding allylated products were afforded in good to excellent (up to 99%) yields with high regioselectivities. This straightforward protocol exhibits good functional group tolerance and scalability.

11.
Org Lett ; 21(12): 4428-4432, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31184170

RESUMO

An indium(0)-metal-mediated efficient synthesis of benzylic hydroperoxides is described. The reaction proceeds efficiently with a broad range of benzyl bromides under aerobic conditions at room temperature to afford benzyl hydroperoxides in good to excellent yields. In addition, the tandem hydroperoxidation-Michael addition of ( E)-1-(bromomethyl)-2-(2-nitrovinyl)benzene was also demonstrated.

12.
Ann Bot ; 123(7): 1147-1158, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-30861064

RESUMO

BACKGROUND AND AIMS: The inverse correlation between atmospheric CO2 partial pressure (pCO2) and stomatal frequency in many plants has been widely used to estimate palaeo-CO2 levels. However, apparent discrepancies exist among the obtained estimates. This study attempts to find a potential proxy for palaeo-CO2 concentrations by analysing the stomatal frequency of Quercus glauca (section Cyclobalanopsis, Fagaceae), a dominant species in East Asian sub-tropical forests with abundant fossil relatives. METHODS: Stomatal frequencies of Q. glauca from three material sources were analysed: seedlings grown in four climatic chambers with elevated CO2 ranging from 400 to 1300 ppm; extant samples collected from 14 field sites at altitudes ranging from 142 to 1555 m; and 18 herbarium specimens collected between 1930 and 2011. Stomatal frequency-pCO2 correlations were determined using samples from these three sources. KEY RESULTS: An inverse correlation between stomatal frequency and pCO2 was found for Q. glauca through cross-validation of the three material sources. The combined calibration curves integrating data of extant altitudinal samples and historical herbarium specimens improved the reliability and accuracy of the curves. However, materials in the climatic chambers exhibited a weak response and relatively high stomatal frequency possibly due to insufficient treatment time. CONCLUSIONS: A new inverse stomatal frequency-pCO2 correlation for Q. glauca was determined using samples from three sources. These three material types show the same response, indicating that Q. glauca is sensitive to atmospheric pCO2 and is an ideal proxy for palaeo-CO2 levels. Quercus glauca is a nearest living relative (NLR) of section Cyclobalanopsis fossils, which are widely distributed in the strata of East Asia ranging from the Eocene to Pliocene, thereby providing excellent materials to reconstruct the atmospheric CO2 concentration history of the Cenozoic. Quercus glauca will add to the variety of proxies that can be widely used in addition to Ginkgo and Metasequoia.


Assuntos
Quercus , Dióxido de Carbono , Ásia Oriental , Fósseis , Folhas de Planta , Reprodutibilidade dos Testes
13.
Chem Commun (Camb) ; 54(66): 9230-9233, 2018 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-30065995

RESUMO

A chiral SPINOL derived phosphoric acid-catalyzed asymmetric N-alkylation reaction of indoles with cyclic α-diaryl-substituted N-acyl imines, which are generated in situ from 3-aryl 3-hydroxyisoindolinones, has been demonstrated. The transformation proceeds smoothly with a broad range of indoles and isoindolinone alcohols. A variety of indole derived N-alkylated tetrasubstituted chiral aminals were afforded in moderate to good yields (50-79%) with excellent enantioselectivities (up to 98% ee).

14.
Ann Bot ; 115(5): 777-88, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25681824

RESUMO

BACKGROUND AND AIMS: The inverse relationship between atmospheric CO2 partial pressure (pCO2) and stomatal frequency in many species of plants has been widely used to estimate palaeoatmospheric CO2 (palaeo-CO2) levels; however, the results obtained have been quite variable. This study attempts to find a potential new proxy for palaeo-CO2 levels by analysing stomatal frequency in Quercus guyavifolia (Q. guajavifolia, Fagaceae), an extant dominant species of sclerophyllous forests in the Himalayas with abundant fossil relatives. METHODS: Stomatal frequency was analysed for extant samples of Q. guyavifolia collected from17 field sites at altitudes ranging between 2493 and 4497 m. Herbarium specimens collected between 1926 and 2011 were also examined. Correlations of pCO2-stomatal frequency were determined using samples from both sources, and these were then applied to Q. preguyavaefolia fossils in order to estimate palaeo-CO2 concentrations for two late-Pliocene floras in south-western China. KEY RESULTS: In contrast to the negative correlations detected for most other species that have been studied, a positive correlation between pCO2 and stomatal frequency was determined in Q. guyavifolia sampled from both extant field collections and historical herbarium specimens. Palaeo-CO2 concentrations were estimated to be approx. 180-240 ppm in the late Pliocene, which is consistent with most other previous estimates. CONCLUSIONS: A new positive relationship between pCO2 and stomatal frequency in Q. guyavifolia is presented, which can be applied to the fossils closely related to this species that are widely distributed in the late-Cenozoic strata in order to estimate palaeo-CO2 concentrations. The results show that it is valid to use a positive relationship to estimate palaeo-CO2 concentrations, and the study adds to the variety of stomatal density/index relationships that available for estimating pCO2. The physiological mechanisms underlying this positive response are unclear, however, and require further research.


Assuntos
Dióxido de Carbono/metabolismo , Estômatos de Plantas/fisiologia , Quercus/fisiologia , Atmosfera , Fósseis , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia , Estômatos de Plantas/anatomia & histologia , Quercus/anatomia & histologia
15.
Chem Commun (Camb) ; (46): 4931-3, 2007 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-18361373

RESUMO

AgBiS2 microspheres synthesized by using PEG as a template serve as active catalysts for the polymerization of an alkylsilane, C18H37SiH3 with water to form silanols.


Assuntos
Silanos/síntese química , Compostos de Prata/síntese química , Sulfetos/síntese química , Catálise , Microesferas , Polietilenoglicóis/química , Polímeros/síntese química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
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