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1.
Chemistry ; 30(36): e202400950, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38655749

RESUMEN

It is usually believed that doping with photosensitizers capable of generating singlet oxygen (1O2) plays a pivotal role in enhancing the afterglow performance of semiconducting polymer nanoparticles (SPNs). However, the effect of doping photosensitizer bearing electron-withdrawing groups has not been reported. Here we report the effect of doping with six photosensitizers possessing different electron-withdrawing groups on the afterglow performance of SPNs using poly[(9,9-di(2-ethylhexyl)-9H-fluo-rene-2,7-vinylene)-co-(1-methoxy-4-(2-ethylhexyloxy)-2,5-phenylenevinylene)] (PF-MEHPPV) as substrate. It was found that the afterglow performance of SPNs was significantly influenced by doping with photosensitizers bearing electron-withdrawing groups. For the doped photosensitizers with strong electron-withdrawing groups, the stronger the electron-withdrawing ability of the group, the worse of the afterglow performance of the SPN regardless of the 1O2 generation ability of the photosensitizer. When the doped photosensitizer exhibited weak or none electron-withdrawing effect, the 1O2 generation ability of the photosensitizer played a dominant role on the afterglow performance of the SPNs. This work deepens the understanding of the design and synthesis of SPNs with different afterglow properties.

2.
BMC Nephrol ; 25(1): 125, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589792

RESUMEN

BACKGROUND: Sepsis and acute kidney injury (AKI) are common severe diseases in the intensive care unit (ICU). This study aimed to estimate the attributable mortality of AKI among critically ill patients with sepsis and to assess whether AKI was an independent risk factor for 30-day mortality. METHODS: The information we used was derived from a multicenter prospective cohort study conducted in 18 Chinese ICUs, focusing on septic patients post ICU admission. The patients were categorized into two groups: those who developed AKI (AKI group) within seven days following a sepsis diagnosis and those who did not develop AKI (non-AKI group). Using propensity score matching (PSM), patients were matched 1:1 as AKI and non-AKI groups. We then calculated the mortality rate attributable to AKI in septic patients. Furthermore, a survival analysis was conducted comparing the matched AKI and non-AKI septic patients. The primary outcome of interest was the 30-day mortality rate following the diagnosis of sepsis. RESULTS: Out of the 2175 eligible septic patients, 61.7% developed AKI. After the application of PSM, a total of 784 septic patients who developed AKI were matched in a 1:1 ratio with 784 septic patients who did not develop AKI. The overall 30-day attributable mortality of AKI was 6.6% (95% CI 2.3 ∼ 10.9%, p = 0.002). A subgroup analysis revealed that the 30-day attributable mortality rates for stage 1, stage 2, and stage 3 AKI were 0.6% (95% CI -5.9 ∼ 7.2%, p = 0.846), 4.7% (95% CI -3.1 ∼ 12.4%, p = 0.221) and 16.8% (95% CI 8.1 ∼ 25.2%, p < 0.001), respectively. Particularly noteworthy was that stage 3 AKI emerged as an independent risk factor for 30-day mortality, possessing an adjusted hazard ratio of 1.80 (95% CI 1.31 ∼ 2.47, p < 0.001). CONCLUSIONS: The overall 30-day attributable mortality of AKI among critically ill patients with sepsis was 6.6%. Stage 3 AKI had the most significant contribution to 30-day mortality, while stage 1 and stage 2 AKI did not increase excess mortality.


Asunto(s)
Lesión Renal Aguda , Sepsis , Humanos , Estudios Retrospectivos , Estudios Prospectivos , Enfermedad Crítica , Lesión Renal Aguda/diagnóstico , Unidades de Cuidados Intensivos , Sepsis/complicaciones
3.
BMC Pulm Med ; 24(1): 110, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38438849

RESUMEN

BACKGROUND: Both sepsis and acute respiratory distress syndrome (ARDS) are common severe diseases in the intensive care unit (ICU). There is no large-scale multicenter study to clarify the attributable mortality of ARDS among septic patients. This study aimed to evaluate the excess mortality of ARDS in critically ill patients with sepsis. METHODS: The data were obtained from a multicenter, prospective cohort study in 18 Chinese ICUs between January 2014 and August 2015. The study population was septic patients after ICU admission. The patients were categorized into two groups: those who developed ARDS (ARDS group) within seven days following a sepsis diagnosis and those who did not develop ARDS (non-ARDS group). Applying propensity score matching (PSM), patients were matched 1:1 as ARDS and non-ARDS groups. Mortality attributed to ARDS was calculated. Subsequently, we conducted a survival analysis to estimate the impact of ARDS on mortality. The primary endpoint was 30-day mortality after sepsis diagnosis. RESULTS: 2323 septic patients were eligible, 67.8% developed ARDS. After PSM, 737 patients with ARDS were matched 1:1 with 737 non-ARDS patients. ARDS's overall 30-day attributable mortality was 11.9% (95% CI 7.5-16.3%, p < 0.001). Subgroup analysis showed that the 30-day attributable mortality of mild, moderate, and severe ARDS was 10.5% (95% CI 4.0-16.8%, p < 0.001), 11.6% (95% CI 4.7-18.4%, p < 0.001) and 18.1% (95% CI 4.5-30.9%, p = 0.006), respectively. ARDS was an independent risk factor for 30-day mortality, with adjusted hazard ratios of 1.30 (95% CI 1.03-1.64, p = 0.027), 1.49 (95% CI 1.20-1.85, p < 0.001), and 1.95 (95% CI 1.51-2.52, p < 0.001) for mild, moderate, and severe ARDS, respectively. CONCLUSIONS: The overall 30-day attributable mortality of ARDS among critically ill patients with sepsis was 11.9%. Compared with mild and moderate ARDS, severe ARDS contributed more to death. ARDS was significantly associated with an increase in the 30-day mortality.


Asunto(s)
Síndrome de Dificultad Respiratoria , Sepsis , Humanos , Enfermedad Crítica , Estudios Prospectivos , Estudios Retrospectivos , Sepsis/complicaciones
4.
BMC Musculoskelet Disord ; 25(1): 24, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38166963

RESUMEN

OBJECTIVE: To evaluate the diagnostic values of serum platelet count (PC), mean platelet volume ratio (MPV), platelet count to mean platelet volume ratio (PVR), platelet to lymphocyte ratio (PLR), platelet to neutrophil ratio (PNR), PC/Albumin-globulin ratio (PC/AGR), and PC/C-reactive protein (PC/ CRP) in the diagnosis of periprosthetic joint infection (PJI). METHODS: The medical records were retrospectively analyzed of the 158 patients who had undergone hip or knee revisions from January 2018 to May 2022. Of them, 79 cases were diagnosed with PJI and 79 with aseptic loosening (AL). PJI was defined using the Musculoskeletal Infection Society criteria. The plasma levels of CRP, the erythrocyte sedimentation rate (ESR), PC, MPV, PVR, PLR, PNR, PC/AGR, and PC/CRP in the 2 groups were recorded and analyzed. In addition, tests were performed according to different joint types. The receiver operating characteristic curve was used to calculate the sensitivity and specificity of each indicator. The diagnostic value for each indicator was calculated according to the area under the curve (AUC). RESULTS: The PC, PVR, PLR and PC/AGR levels in the PJI group were significantly higher than those in the AL group, while PC/CRP levels were significantly lower (P < 0.001). The AUC for PC/CRP, and PC/AGR was 0.804 and 0.802, respectively, which were slightly lower than that of CRP (0.826) and ESR (0.846). ROC analysis for PC/CRP, and PC/AGR revealed a cut-off value of 37.80 and 160.63, respectively, which provided a sensitivity of 73.42% and 84.81% and a specificity of 75.95% and 65.82% for PJI. The area under the curve of PLR and PC was 0.738 and 0.702. The area under the curve values for PVR, PNR, and MPV were 0.672, 0.553, and 0.544, respectively. CONCLUSIONS: The results of this study suggest that PC, PLR, PC/CRP, and PC/AGR values do not offer significant advantages over ESR or CRP values when employed for the diagnosis of PJI. PVR, PNR, and MPV were not reliable in the diagnosis of PJI.


Asunto(s)
Artritis Infecciosa , Artroplastia de Reemplazo de Cadera , Infecciones Relacionadas con Prótesis , Humanos , Biomarcadores , Estudios Retrospectivos , Infecciones Relacionadas con Prótesis/cirugía , Artroplastia de Reemplazo de Cadera/efectos adversos , Proteína C-Reactiva/análisis , Sensibilidad y Especificidad , Artritis Infecciosa/cirugía , Sedimentación Sanguínea
5.
Plant Physiol ; 188(2): 1111-1128, 2022 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-34865119

RESUMEN

Chromosome segregation must be under strict regulation to maintain chromosome euploidy and stability. Cell Division Cycle 20 (CDC20) is an essential cell cycle regulator that promotes the metaphase-to-anaphase transition and functions in the spindle assembly checkpoint, a surveillance pathway that ensures the fidelity of chromosome segregation. Plant CDC20 genes are present in multiple copies, and whether CDC20s have the same functions in plants as in yeast and animals is unclear, given the potential for divergence or redundancy among the multiple copies. Here, we studied all three CDC20 genes in rice (Oryza sativa) and constructed two triple mutants by clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9-mediated genome editing to explore their roles in development. Knocking out all three CDC20 genes led to total sterility but did not affect vegetative development. Loss of the three CDC20 proteins did not alter mitotic division but severely disrupted meiosis as a result of asynchronous and unequal chromosome segregation, chromosome lagging, and premature separation of chromatids. Immunofluorescence of tubulin revealed malformed meiotic spindles in microsporocytes of the triple mutants. Furthermore, cytokinesis of meiosis I was absent or abnormal, and cytokinesis II was completely prevented in all mutant microsporocytes; thus, no tetrads or pollen formed in either cdc20 triple mutant. Finally, the subcellular structures and functions of the tapetum were disturbed by the lack of CDC20 proteins. These findings demonstrate that the three rice CDC20s play redundant roles but are indispensable for faithful meiotic chromosome segregation and cytokinesis, which are required for the production of fertile microspores.


Asunto(s)
División Celular/genética , Segregación Cromosómica/genética , Citocinesis/genética , Meiosis/genética , Oryza/genética , Productos Agrícolas/genética , Regulación de la Expresión Génica de las Plantas , Genes de Plantas
6.
J Phys Chem A ; 126(3): 453-461, 2022 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-35023742

RESUMEN

A joint experimental and theoretical investigation of the valence shell excitations of carbon tetrachloride has been performed by fast electron scattering and time dependent density functional theory calculations. At a collision energy of 1.5 keV and an energy resolution of about 70 meV, the dipole-forbidden transition of a1σ* ← 2t1 has been clearly observed at large momentum transfers, and its excitation energy of 6.15 eV and line width of 0.72 eV have been determined. Two new features are also recognized at 9.97 and 10.26 eV. The generalized oscillator strengths of the excited states at 5-11.3 eV have been determined from the measured spectra. The calculated generalized oscillator strength of the a1σ* ← 2t1 transition with the vibronic effect shows better agreement with the experiment, and the vibronic effect also accounts for its nonzero intensity at zero squared momentum transfer. The optical oscillator strengths of the valence shell excitations have also been obtained by extrapolating the generalized oscillator strengths to the limit of zero squared momentum transfer. The integral cross sections have been systematically determined from the threshold to 5000 eV by means of the BE-scaling method. The present oscillator strengths and cross sections provide the fundamental data of carbon tetrachloride and have important applications in photochemical modeling for atmospheric physics.

7.
Environ Res ; 215(Pt 3): 114401, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36167112

RESUMEN

Cyanobacteria salvage is widely used to deal with massive cyanobacterial blooms. Improper disposal of salvaged cyanobacteria would cause secondary pollution. Black soldier fly (Hermetia illucens) larvae (BSFL) can bio-convert organic wastes into larval biomass, which is rich in protein and lipid. This study evaluated the possibility of using BSFL composting for salvaged cyanobacteria treatment. Results showed that increasing salvaged cyanobacteria waste (CW) content (from 0 to 50%, dry weight basis) extended BSFL development time, e.g., BSFL fed with 50% CW needed 14 days more to finish development than Control (0% CW). The CW content (0-20%) in feeding substrates had no significant effect on BSFL body length and weight. Whereas further increase of CW content (from 20 to 50%) led to significant reductions in substrate-to-BSFL biomass conversion ratio, body size, body weight, and crude protein content of BSFL. Meanwhile, the presence of salvaged cyanobacteria in the feeding substrate reduced the degradation efficiency of feeding substrate. The dissolved organic matter (DOM) results demonstrated that the increased salvaged cyanobacteria content made it more difficult for BSFL to degrade the feeding substrate into simple organic matter and further into humic-like substances. Furthermore, salvaged cyanobacteria in feeding substrates affected the intestinal microbial community significantly. With 20% CW content in the feeding substrate, the relative abundance of Firmicutes decreased from 92.43 to 81.24%, while the relative abundance of Proteobacteria and Bacteroidetes increased from 4.10 to 2.93-8.75% and 7.51%, respectively. BSFL composting is feasible to convert salvaged cyanobacteria into insect biomass. However, the salvaged cyanobacteria content in the feeding substrate should be carefully controlled (e.g., less than 30%).


Asunto(s)
Compostaje , Cianobacterias , Dípteros , Animales , Sustancias Húmicas , Larva , Lípidos
8.
Angew Chem Int Ed Engl ; 61(16): e202200537, 2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-35148015

RESUMEN

The discovered giant clusters are always highly symmetric owing to the spontaneous assembly of one or two basic units. Herein we report the Gd44 Co28 crown and Gd95 Co60 cage, formulated as [Gd44 Co28 (IDA)20 (OH)72 (CO3 )12 (OAc)28 (H2 O)64 ]⋅(ClO4 )24 and [Na4 Gd95 Co60 (IDA)40 (OH)150 (CO3 )40 (OAc)58 (H2 O)164 ] ⋅ (ClO4 )41 (H2 IDA=iminodiacetic acid), respectively, by providing a library containing multiple low-nuclearity units. The heart-like units and crown-like tetramer found in both compounds indicate unprecedented assembly levels, leading to an atypical geometry characteristic compared to the giant clusters directly assembled by regular units. These two clusters not only significantly increase the size of Ln-Co clusters but also exhibit the enhanced magnetic entropy change at ultra-low temperatures. This work provided an effective way to fabricate cluster compounds with giant size and geometry complexity simultaneously.

9.
J Org Chem ; 86(23): 16511-16517, 2021 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-34784221

RESUMEN

A mechanism study for Pd(II)-catalyzed C(sp3)-H activation using a self-cleaving chlorotetrafluoroethylsulfinyl (-SOCF2CF2Cl) auxiliary as a directing group is reported. Mechanistic studies reveal that (1) the auxiliary group is crucial for C(sp3)-H activation, (2) the reaction undergoes a C(sp3)-H olefination-Michael addition-removal of the auxiliary sequence, (3) the removal of the auxiliary (SORf) is most likely the alcoholic solvolysis of the -SOCF2CF2Cl group on the N-tri-substituted sulfonamides, and (4) the C(sp3)-H cleavage is involved in the rate-determining step.


Asunto(s)
Paladio , Catálisis
10.
New Phytol ; 228(6): 1897-1913, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32712992

RESUMEN

Climate-driven phenological change across local spatial gradients leads to leaf shape variation. At higher elevations, leaves of broadleaf species tend to become narrower, but the underlying molecular mechanism is largely unknown. In this study, a series of morphometric analyses and biochemical assays, combined with functional identification in apple, were performed. We show that the decrease in apple leaf width with increasing altitude is controlled by a basic/helix-loop-helix transcription factor (bHLH TF), MdbHLH3. The MdbHLH3-overexpressing lines have a lower transcript abundance of MdPIN1 encoding an auxin efflux carrier but a higher transcript abundance of MdGH3-2 encoding a putative auxin amido conjugate synthase, resulting in a lower free auxin concentration; feeding the transgenic leaves with exogenous auxin partially restores leaf width. MdbHLH3 transcriptionally suppresses and activates MdPIN1 and MdGH3-2, respectively, by specifically binding to their promoters. This alters auxin homeostasis and transport, consequently leading to changes in leaf shape. These findings suggest that the bHLH TF MdbHLH3 directly modulates auxin signaling in controlling leaf shape in response to local spatial gradients in apple.


Asunto(s)
Malus , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Regulación de la Expresión Génica de las Plantas , Ácidos Indolacéticos , Malus/genética , Malus/metabolismo , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
11.
Inorg Chem ; 59(12): 7900-7904, 2020 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-32495619

RESUMEN

Two high-nuclearity lanthanide-transition metal clusters with the general formula [Ln18CoIICoIII6(OH)14(CO3)9(CH3CH2COO)6(dea)12(H2O)30]·(NO3)8·Cl4·(CH3CH2OH)6·(H2O)12 (Ln18Co7, Ln = Gd (1) and Dy (2)) have been obtained by reacting CoCl2·6H2O, Ln(NO3)3·6H2O, and a mixture of ligands consisting of propionate and diethanolamine (H2dea). Crystal structural analysis exhibits two three-blade propellers composed of the CoIII3Ln9 units connected by one CoII ion and three CO32- ions, which assemble into a double-propeller-like structure (Ln18CoIICoIII6). Magnetocaloric effect (MCE) studies indicate that Gd18Co7 exhibits a large entropy change (-ΔSm) of 36.9 J kg-1 K-1.

12.
Cryobiology ; 94: 95-99, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32304703

RESUMEN

Sperm cryopreservation is an essential approach for assisted reproduction and genetic resources conservation in captive giant pandas. Cryopreservation, however, leads to a significant decrease in sperm quality and, consequently, a low fertilization rate. Therefore, it is mandatory to disclose more suitable and efficient freezing strategies for sperm cryopreservation. In the present study, we compared for the first time the performance of two commercial freeze extender (INRA96 versus TEST) freezing methods on post-thawed semen quality. Semen cryopreserved with the INRA96 showed better total motility (73.00 ± 4.84% vs 57.56 ± 3.60%, P < 0.001), membrane integrity (60.92 ± 2.27% vs 40.53 ± 2.97%, P < 0.001) and acrosome integrity (90.39 ± 2.74% vs 84.26 ± 4.27%, P < 0.05) than stored with TEST. There was no significant difference in DNA integrity after thawing between the two extenders (95.69 ± 3.60% vs 94.26 ± 4.84%). In conclusion, the INRA96 method showed to be better for giant panda sperm cryopreservation and should therefore be recommended for use in order to increase success of artificial insemination.


Asunto(s)
Criopreservación/métodos , Crioprotectores/farmacología , Preservación de Semen/métodos , Semen , Ursidae , Animales , Masculino , Análisis de Semen , Espermatozoides/efectos de los fármacos
13.
Sheng Li Xue Bao ; 72(3): 399-406, 2020 Jun 25.
Artículo en Zh | MEDLINE | ID: mdl-32572437

RESUMEN

Calcitonin gene-related peptide (CGRP) is a neuropeptide coded by the calcitonin gene and divided into α and ß subtypes. CGRP is widely distributed throughout the human body and highly expressed in the peripheral and central nervous system. Studies have shown that CGRP plays a role in a variety of physiological and pathophysiological activities, such as the formation and transmission of nociceptive signal, as well as the regulation of cardiovascular function. Recently, more and more researches have shown that CGRP is involved in the regulation of synaptic plasticity, cognitive function and learning memory in the central nervous system. This paper reviews the role of CGRP in regulation of synaptic plasticity and process of emotional memory, hoping to provide a new molecular target and theoretical basis for clinical treatment of neurological diseases.


Asunto(s)
Péptido Relacionado con Gen de Calcitonina , Calcitonina , Sistema Nervioso Central , Humanos , Memoria , Plasticidad Neuronal
14.
Plant Physiol ; 176(1): 819-835, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29158333

RESUMEN

This study aimed at elucidating regulatory components behind floral organ identity determination and tissue development. It remains unclear how organ identity proteins facilitate development of organ primordia into tissues with a determined identity, even though it has long been accepted that floral organ identity is genetically determined by interaction of identity genes according to the ABC model. Using the chromatin immunoprecipitation sequencing technique, we identified OsTGA10, encoding a bZIP transcription factor, as a target of the MADS box protein OsMADS8, which is annotated as an E-class organ identity protein. We characterized the function of OsTGA10 using genetic and molecular analyses. OsTGA10 was preferentially expressed during stamen development, and mutation of OsTGA10 resulted in male sterility. OsTGA10 was required for tapetum development and functioned by interacting with known tapetum genes. In addition, in ostga10 stamens, the hallmark cell wall thickening of the endothecium was defective. Our findings suggest that OsTGA10 plays a mediator role between organ identity determination and tapetum development in rice stamen development, between tapetum development and microspore development, and between various regulatory components required for tapetum development. Furthermore, the defective endothecium in ostga10 implies that cell wall thickening of endothecium is dependent on tapetum development.


Asunto(s)
Flores/crecimiento & desarrollo , Flores/metabolismo , Proteínas de Dominio MADS/metabolismo , Oryza/crecimiento & desarrollo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Pared Celular/metabolismo , ADN de Plantas/metabolismo , Epistasis Genética , Flores/citología , Flores/ultraestructura , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Oryza/genética , Fenotipo , Homología de Secuencia de Aminoácido
15.
Sheng Li Xue Bao ; 71(6): 839-845, 2019 Dec 25.
Artículo en Zh | MEDLINE | ID: mdl-31879739

RESUMEN

The purpose of this study was to explore the effects of calcitonin gene-related peptide (CGRP) on the long-term depression (LTD) of hippocampus in mice. Sixty C57BL/6J mice (30 days old) were randomly divided into control group, three CGRP (50, 100, and 200 nmol/L) groups, CGRP + CGRP8-37 group and CGRP + APV group (10 mice for each group). The effects of exogenous application of different concentrations of CGRP on synaptic plasticity and LTD in hippocampus of mice were detected by in vitro recording of local field potential. The results showed that higher doses (100 and 200 nmol/L) of CGRP significantly enhanced the induction of LTD in the hippocampus. Moreover, CGRP increased the magnitude of N-methyl-D-aspartate (NMDA) receptor-mediated excitatory postsynaptic currents. The above-mentioned effects of CGRP were blocked by either CGRP selective antagonist CGRP8-37 or NMDA receptor antagonist APV. These results suggest that CGRP can dose-dependently enhance the induction of LTD in hippocampus of mice, and the underlying mechanism involves the mediation of NMDA receptor function.


Asunto(s)
Péptido Relacionado con Gen de Calcitonina , Hipocampo , Animales , Péptido Relacionado con Gen de Calcitonina/farmacología , Hipocampo/efectos de los fármacos , Depresión Sináptica a Largo Plazo/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Distribución Aleatoria
17.
Ann Bot ; 121(2): 255-266, 2018 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-29267935

RESUMEN

Background and Aims: To understand the link between species diversity and phenotype developmental evolution is an important issue in evolutionary biology. Yarrows in the genus Achillea (Asteraceae) show a great diversity in leaf serrate or pinnate dissection patterns. In Arabidopsis thaliana, the development of leaf serration requires the activity of the transcription factor CUC2. Does this regulator also work for leaf dissections of the Asteraceae plants? If so, how do the conserved regulatory 'tools' work differently to produce diverse leaf forms? Methods: Seedling leaf morphology was observed, and morphogenesis of leaf serration or lobes was examined by scanning electron microscopy (SEM). NAM genes, orthologues of arabidopsis CUC2, were isolated from A. acuminata with serrate leaves and A. asiatica with three-pinnatisect leaves, respectively. By means of whole-mount in situ mRNA hybridization and two quantitative gene expression assays, the droplet digital PCR (ddPCR) and quantitative real-time PCR (qPCR), expression patterns of the NAM genes during leaf dissection development were checked in both species for comparison. Key Results: For both species, the development of leaf dissection initiated when a leaf blade was about 300-400 µm long. In A. acuminata, in situ hybridization showed NAM expression signals at leaf margins where teeth are growing, or later on, in the sinuses of the teeth, whilst in A. asiatica, hybridization signals appear not only on leaf margins but further on the margins of leaf lobes. Both ddPCR and qPCR revealed a continuous decline of AacNAM expression from the early to the late developmental stages of a single leaf of A. acuminata, whereas a relatively long maintenance and fluctuation of AasNAM expression was seen in a leaf of A. asiatica. Conclusions: Differential spatiotemporal patterns of NAM expression were found between the two yarrow species during development of leaf dissection. This study provides the first evidence for NAM activity in the development of leaf dissection of the Asteraceae plants, and demonstrates that leaf form diversity is correlated to the altered NAM expression dynamic.


Asunto(s)
Achillea/anatomía & histología , Genes de Plantas/fisiología , Hojas de la Planta/anatomía & histología , Achillea/genética , Achillea/ultraestructura , Paseo de Cromosoma , Regulación de la Expresión Génica de las Plantas , Genes de Plantas/genética , Hibridación in Situ , Microscopía Electrónica de Rastreo , Filogenia , Hojas de la Planta/genética , Hojas de la Planta/ultraestructura , Proteínas de Plantas/genética , Proteínas de Plantas/fisiología , Reacción en Cadena en Tiempo Real de la Polimerasa , Plantones/anatomía & histología , Plantones/ultraestructura , Factores de Transcripción/genética , Factores de Transcripción/fisiología
18.
Org Biomol Chem ; 16(24): 4429-4432, 2018 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-29808881

RESUMEN

Four Hamilton receptors and four cyanuric acid modules were introduced into the tetraphenylethylene skeleton to form HTPE and CTPE, respectively. Upon 1 : 1 mixing of HTPE and CTPE in apolar dilute solution, a self-assembled supramolecular network was formed via multiple intermolecular hydrogen bonding interactions. The intramolecular rotation of phenyls in TPE skeletons was restricted, and thus the system became highly luminescent. Upon the addition of a hydrogen bonding competitive solvent to destroy the network, the fluorescence emission was substantially quenched. Besides, the fluorescence of the system could be further tuned by the addition of Cu2+ and other metal ions.

19.
Zhongguo Zhong Yao Za Zhi ; 43(8): 1563-1570, 2018 Apr.
Artículo en Zh | MEDLINE | ID: mdl-29751701

RESUMEN

Raffinose series oligosaccharides are the transport and storage sugars of many plants, Rehmannia glutinosa is one of the commonly used Chinese herbal medicines, medicinal parts ist he roots. Root and tuber of R. glutinosa contains stachyose, raffinose and other oligosaccharides, but the study about the process of growth and development of other organs in the non-structural changes in sugar content is rare.In this study, leaves, stems and roots of R. glutinosa were used as materials to analyze the diurnal variation and the changes of sugar content of sucrose, raffinose and stachyose in different organs of R. glutinosa. The results showed that the content of sucrose in R. glutinosa leaves gradually increased from seedling stage.However, the content of stachyose did not change much at the early stage of growth, and the stachyose rapidly increased at the later stage of growth. The raffinose content gradually decreased throughout the growing season, young leaves of R. glutinosa have higher ability to sucrose synthesis than mature leaves, while mature leaf has higher raffinose and stachyose synthesis ability than young leaves. Sucrose and stachyose content in stem gradually increased, while there was little change in raffinose content. The content of raffinose and stachyose in root increased rapidly from the beginning of fast growing period, while the content of sucrose did not change much. The content of sucrose in leaves of R. glutinosa did not change much at day and night, while the daily changes of raffinose and stachyose contents were very obvious. The contents of raffinose and stachyose in daytime were higher than those at night. The content of raffinose in root and stem was not changed much, but the change of stachyose in root, stem and leaf was very obvious, especially in stem and leaf. In summary, the leaf is the main synthetic organ of raffinose, leaves, stems and roots are stachyose synthesis organ. Sucrose, raffinose and stachyose are the major transport forms of carbohydrates in R. glutinosa.


Asunto(s)
Rehmannia , Carbohidratos , Humanos , Masculino , Oligosacáridos , Hojas de la Planta
20.
J Am Chem Soc ; 139(36): 12390-12393, 2017 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-28805383

RESUMEN

A Cu(II)-catalyzed ortho-selective functionalization of free phenols with trifluoroborates to afford Csp2-Csp3 coupling products under mild conditions has been developed. A variety of functional groups on the phenol and the potassium aminomethyltrifluoroborate substrates were found compatible, furnishing the corresponding products in moderate to excellent yields. A single-electron transfer radical coupling mechanism involving a six-membered transition state is proposed to rationalize the high levels of ortho-selectivity in the reaction. This protocol provides straightforward access to ortho-aminomethyl-substituted phenols, unnatural amino acids and other bioactive small molecules.


Asunto(s)
Aminas/química , Cobre/química , Fenoles/química , Catálisis , Metilación
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