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1.
Planta ; 260(3): 58, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39039384

RESUMEN

MAIN CONCLUSION: A genome-wide analysis had identified 642 ABA core component genes from 20 plant species, which were further categorized into three distinct subfamilies. The gene structures and evolutionary relationships of these genes had been characterized. PP2C_1, PP2C_2, and SnRK2_1 had emerged as key players in mediating the ABA signaling transduction pathway, specifically in rice, in response to abiotic stresses. The plant hormone abscisic acid (ABA) is essential for growth, development, and stress response, relying on its core components, pyrabactin resistance, pyrabactin resistance-like, and the regulatory component of ABA receptor (PYR/PYL/RCAR), 2C protein phosphatase (PP2C), sucrose non-fermenting-1-related protein kinase 2 (SnRK2). However, there's a lack of research on their structural evolution and functional differentiation across plants. Our study analyzed the phylogenetic, gene structure, homology, and duplication evolution of this complex in 20 plant species. We found conserved patterns in copy number and homology across subfamilies. Segmental and tandem duplications drove the evolution of these genes, while whole-genome duplication (WGD) expanded PYR/PYL/RCAR and PP2C subfamilies, enhancing environmental adaptation. In rice and Arabidopsis, the PYR/PYL/RCAR, PP2C, and SnRK2 genes showed distinct tissue-specific expression and responded to various stresses. Notably, PP2C_1 and PP2C_2 interacted with SnRK2_1 and were crucial for ABA signaling in rice. These findings offered new insights into ABA signaling evolution, interactions, and integration in green plants, benefiting future research in agriculture, evolutionary biology, ecology, and environmental science.


Asunto(s)
Ácido Abscísico , Evolución Molecular , Genoma de Planta , Oryza , Filogenia , Transducción de Señal , Oryza/genética , Oryza/metabolismo , Oryza/fisiología , Ácido Abscísico/metabolismo , Transducción de Señal/genética , Genoma de Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Duplicación de Gen , Estrés Fisiológico/genética , Reguladores del Crecimiento de las Plantas/metabolismo , Proteína Fosfatasa 2C/genética , Proteína Fosfatasa 2C/metabolismo , Arabidopsis/genética , Arabidopsis/fisiología
2.
Rev Cardiovasc Med ; 25(4): 147, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-39076552

RESUMEN

Background: This study aims to investigate the association between nine tag single nucleotide polymorphisms (SNPs) in the C3 gene locus and the risk of coronary artery disease (CAD) as well as lipid levels in the Chinese population, and to further explore the interactions between SNPs and environmental factors that may be associated with CAD risk. Methods: A case-control study was conducted to investigate the association between CAD and C3 gene polymorphisms in a hospital setting. The study consisted of 944 CAD patients with a mean age of 55.97 ± 10.182 years and 897 non-CAD controls with a mean age of 55.94 ± 9.162 years. There were 565 males and 288 females in the CAD group and 583 males and 314 females in the control group. TagSNPs in the C3 gene were identified by employing the improved multiplex ligation detection reaction (iMLDR) technique, and multifactor dimensionality reduction (MDR) analysis was utilized to investigate the C3 gene-environment and gene-gene interactions in relation to the risk of CAD. Results: Results of the polymorphism study indicated that the CC genotype of rs7257062 was more frequent in the CAD group compared to the control group (10.9% vs 7.7%), with a statistically significant difference (p = 0.009). Moreover, the TT and CC + CT genotype groups of rs7257062 in the CAD subgroup showed a significant difference in terms of serum triglyceride levels (2.326 ± 1.889 vs 2.059 ± 1.447, p = 0.019). Analysis of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), apolipoprotein A (ApoA), and apolipoprotein B (ApoB) levels revealed no significant differences between the TT and CC + CT genotypes. Furthermore, no significant differences in serum lipid levels were observed between genotypes of the other SNPs. Multivariable logistic analysis, controlling for gender, age, body mass index (BMI), triglycerides (TG), TC, HDL-C, LDL-C, ApoA and ApoB, demonstrated that rs7257062 was still an independent risk factor of CAD (OR = 1.499, 95% CI: 1.036-2.168, p = 0.032). MDR analysis revealed that the rs7257062 interacted significantly with environmental factors such as smoking, diabetes, hypertension, BMI, and TG (p < 0.05). Conclusions: The rs7257062 variation of the C3 gene could be linked to both lipid balance and the risk of CAD. It is conceivable that the interplay between C3 polymorphisms and environmental elements could account for the etiology of CAD.

3.
Angew Chem Int Ed Engl ; : e202407360, 2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38973064

RESUMEN

The one-step synthesis of tetra-substituted benzenes was accomplished via gold-catalyzed diyne-ene annulation. Distinguished from prior modification methods, this novel strategy undergoes formal [3+3] cyclization, producing polysubstituted benzenes with exceptional efficiency. The critical factor enabling this transformation was the introduction of amides, which were reported for the first time in gold catalysis as covalent nucleophilic co-catalysts. This interesting protocol not only offers a new strategy to achieve functional benzenes with high efficiency, but also enlightens potential new reaction pathways within gold-catalyzed alkyne activation processes.

4.
J Neurosci ; 41(39): 8163-8180, 2021 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-34385359

RESUMEN

Sox10 is a well known factor to control oligodendrocyte (OL) differentiation, and its expression is regulated by Olig2. As an important protein kinase, Akt has been implicated in diseases with white matter abnormalities. To study whether and how Akt may regulate OL development, we generated OL lineage cell-specific Akt1/Akt2/Akt3 triple conditional knock-out (Akt cTKO) mice. Both male and female mice were used. These mutants exhibit a complete loss of mature OLs and unchanged apoptotic cell death in the CNS. We show that the deletion of Akt three isoforms causes downregulation of Sox10 and decreased levels of phosphorylated FoxO1 in the brain. In vitro analysis reveals that the expression of FoxO1 with mutations on phosphorylation sites for Akt significantly represses the Sox10 promoter activity, suggesting that phosphorylation of FoxO1 by Akt is important for Sox10 expression. We further demonstrate that mutant FoxO1 without Akt phosphorylation epitopes is enriched in the Sox10 promoter. Together, this study identifies a novel FoxO1 phosphorylation-dependent mechanism for Sox10 expression and OL differentiation.SIGNIFICANCE STATEMENT Dysfunction of Akt is associated with white matter diseases including the agenesis of the corpus callosum. However, it remains unknown whether Akt plays an important role in oligodendrocyte differentiation. To address this question, we generated oligodendrocyte lineage cell-specific Akt1/Akt2/Akt3 triple-conditional knock-out mice. Akt mutants exhibit deficient white matter development, loss of mature oligodendrocytes, absence of myelination, and unchanged apoptotic cell death in the CNS. We demonstrate that deletion of Akt three isoforms leads to downregulation of Sox10, and that phosphorylation of FoxO1 by Akt is critical for Sox10 expression. Together, these findings reveal a novel mechanism to regulate Sox10 expression. This study may provide insights into molecular mechanisms for neurodevelopmental diseases caused by dysfunction of protein kinases.


Asunto(s)
Encéfalo/metabolismo , Diferenciación Celular/fisiología , Oligodendroglía/citología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Factores de Transcripción SOXE/metabolismo , Médula Espinal/metabolismo , Animales , Apoptosis/fisiología , Femenino , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Masculino , Ratones , Ratones Noqueados , Oligodendroglía/metabolismo , Fosforilación , Proteínas Proto-Oncogénicas c-akt/genética , Factores de Transcripción SOXE/genética , Sustancia Blanca/metabolismo
5.
Neuropathol Appl Neurobiol ; 48(7): e12839, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35881686

RESUMEN

AIMS: Abundant recent evidence has shown that 3-phosphoinositide-dependent protein kinase 1 (PDK1) is activated in Alzheimer's disease (AD). However, it remains unknown whether inhibition of PDK1 in neurons may affect AD-like pathology in animal models of AD. Here, we aim to examine the effects of specific inactivation of neuronal PDK1 on pathology and behaviour in 5×FAD mice and to identify the underlying molecular mechanisms. METHODS: The Cre-loxP system was employed to generate Pdk1 cKO/5×FAD mice, in which PDK1 is inactivated in excitatory neurons in the adult forebrain. Cellular and behavioural techniques were used to examine plaque burden, inflammatory responses and spatial working memory in mice. Biochemical and molecular analyses were conducted to investigate relevant mechanisms. RESULTS: First, Aß deposition was massively decreased and gliosis was highly attenuated in Pdk1 cKO/5×FAD mice compared with 5×FAD mice. Second, memory deficits were significantly improved in Pdk1 cKO/5×FAD mice. Third, APP levels were notably decreased in Pdk1 cKO/5×FAD mice. Fourth, mammalian target of rapamycin (mTOR) signalling and ribosome biogenesis were reduced in Pdk1 cKO/5×FAD mice. CONCLUSIONS: Neuron-specific deletion of PDK1 robustly ameliorates AD-like pathology and improves spatial working memory in 5×FAD mice. We propose that genetic approach to inhibit PDK1 may be an effective strategy to slow AD.


Asunto(s)
Enfermedad de Alzheimer , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora , Animales , Ratones , Enfermedad de Alzheimer/patología , Modelos Animales de Enfermedad , Flavina-Adenina Dinucleótido , Gliosis , Ratones Transgénicos , Placa Amiloide/patología , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/genética
6.
Int J Mol Sci ; 23(13)2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35806345

RESUMEN

This study aims to develop a simple, sensitive, low-cost, environmentally friendly and flexible surface-enhanced Raman scattering (SERS) platform, combined with a portable Raman spectrometer, for the rapid and on-site SERS detection of bacteria. Commercial tobacco packaging paper (TPP) with little background interference was used as a loading medium that effectively adsorbed Au nanoparticles and provided sufficient "hot spots". This Au-tobacco packaging paper (Au-TPP) substrate used as a flexible SERS platform can maximize sample collection by wiping irregular surfaces, and was successfully applied to the on-site and rapid detection of pathogenic bacteria. Raman fingerprints of pathogenic bacteria can be obtained by SERS detection of spiked pork using wipeable Au-TPP, which verifies its value in practical applications. The results collected by SERS were further verified by polymerase chain reaction (PCR) results. It showed several advantages in on-site SERS detection, including accurate discrimination, simple preparation, easy operation, good sensitivity, accuracy and reproducibility. This study indicates that the established flexible SERS platform has good practical applications in pathogenic bacterial identification and other rapid detections.


Asunto(s)
Oro , Nanopartículas del Metal , Bacterias , Reproducibilidad de los Resultados , Espectrometría Raman/métodos
7.
Int J Mol Sci ; 23(3)2022 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-35163280

RESUMEN

The rapid identification of bacterial antibiotic susceptibility is pivotal to the rational administration of antibacterial drugs. In this study, cefotaxime (CTX)-derived resistance in Salmonella typhimurium (abbr. CTXr-S. typhimurium) during 3 months of exposure was rapidly recorded using a portable Raman spectrometer. The molecular changes that occurred in the drug-resistant strains were sensitively monitored in whole cells by label-free surface-enhanced Raman scattering (SERS). Various degrees of resistant strains could be accurately discriminated by applying multivariate statistical analyses to bacterial SERS profiles. Minimum inhibitory concentration (MIC) values showed a positive linear correlation with the relative Raman intensities of I990/I1348, and the R2 reached 0.9962. The SERS results were consistent with the data obtained by MIC assays, mutant prevention concentration (MPC) determinations, and Kirby-Bauer antibiotic susceptibility tests (K-B tests). This preliminary proof-of-concept study indicates the high potential of the SERS method to supplement the time-consuming conventional method and help alleviate the challenges of antibiotic resistance in clinical therapy.


Asunto(s)
Infecciones por Salmonella/inmunología , Salmonella typhimurium/inmunología , Espectrometría Raman/métodos , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Farmacorresistencia Bacteriana/genética , Farmacorresistencia Microbiana/efectos de los fármacos , Humanos , Infecciones por Salmonella/diagnóstico , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/patogenicidad
8.
Molecules ; 27(16)2022 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-36014519

RESUMEN

Aspergillus flavus and Aflatoxins in grain crops give rise to a serious threat to food security and cause huge economic losses. In particular, aflatoxin B1 has been identified as a Class I carcinogen to humans by the International Agency for Research on Cancer (IARC). Compared with conventional methods, Surface-Enhanced Raman Scattering (SERS) has paved the way for the detection of Aspergillus flavus and Aflatoxins in grain crops as it is a rapid, nondestructive, and sensitive analytical method. In this work, the rapid detection of Aspergillus flavus and quantification of Aflatoxin B1 in grain crops were performed by using a portable Raman spectrometer combined with colloidal Au nanoparticles (AuNPs). With the increase of the concentration of Aspergillus flavus spore suspension in the range of 102-108 CFU/mL, the better the combination of Aspergillus flavus spores and AuNPs, the better the enhancement effect of AuNPs solution on the Aspergillus flavus. A series of different concentrations of aflatoxin B1 methanol solution combined with AuNPs were determined based on SERS and their spectra were similar to that of solid powder. Moreover, the characteristic peak increased gradually with the increase of concentration in the range of 0.0005-0.01 mg/L and the determination limit was 0.0005 mg/L, which was verified by HPLC in ppM concentration. This rapid detection method can greatly shorten the detection time from several hours or even tens of hours to a few minutes, which can help to take effective measures to avoid causing large economic losses.


Asunto(s)
Aflatoxinas , Nanopartículas del Metal , Aflatoxina B1 , Aflatoxinas/análisis , Aspergillus flavus , Grano Comestible/química , Oro/farmacología , Humanos
9.
World J Microbiol Biotechnol ; 39(1): 26, 2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36422715

RESUMEN

Grain crops are easily contaminated by fungi due to the existence of various microorganisms in the storage process, especially in humid and warm storage conditions. Compared with conventional methods, surface-enhanced Raman scattering (SERS) has paved the way for the detection of fungi in grain crops as it is a rapid, nondestructive, and sensitive analytical method. In this work, Aspergillus niger, Saccharomyces cerevisiae, Fusarium moniliforme and Trichoderma viride in grain crops were detected using colloidal Au nanoparticles and SERS. The results indicated that different fungi showed different Raman phenotypes, which could be easily characterized by SERS. Combined with multivariate statistical analysis, identification of a variety of fungi could be accomplished rapidly and accurately. This research can be applied for the rapid detection of fungi in the food and biomedical industries.


Asunto(s)
Nanopartículas del Metal , Espectrometría Raman , Espectrometría Raman/métodos , Oro , Análisis Multivariante , Grano Comestible , Productos Agrícolas , Hongos
10.
Chin Chem Lett ; 33(9): 4203-4207, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38107831

RESUMEN

Fluorescence (FL) active 8-aryl guanosine derivatives were prepared and applied for cation mediated self-assembly to form the H-bonded G8-quadruplexes. The p-cyano (p-CN) and 8-anthracene (8-An) substituted guanosines were identified to give the strongest fluorescence with the formation of G8-octamers (G8) both in solution (NMR) and solid state (X-ray). This well-defined G8-octamer system has provided the first direct evidence on the self-assembled G-quadruplex fluorescence emission with aggregation-induced emission (AIE), which could be applied as the foundation for FL molecular probe design toward G-quadruplex recognition.

11.
Neurobiol Dis ; 148: 105212, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33276084

RESUMEN

PDK1 (3-Phosphoinositide dependent protein kinase-1) is a member in the PI3K (phosphatidylinositol 3 kinase) pathway and is implicated in neurodevelopmental disease with microcephaly. Although the role of PDK1 in neurogenesis has been broadly studied, it remains unknown how PDK1 may regulate oligogenesis in the central nervous system (CNS). To address this question, we generated oligodendrocyte (OL) lineage cells specific PDK1 conditional knockout (cKO) mice. We find that PDK1 cKOs display abnormal white matter (WM), massive loss of mature OLs and severe defect in myelination in the CNS. In contrast, these mutants exhibit normal neuronal development and unchanged apoptosis in the CNS. We demonstrate that deletion of PDK1 severely impairs OL differentiation. We show that genetic or pharmacological inhibition of PDK1 causes deficit in the mammalian target of rapamycin (mTor) signaling and down-regulation of Sox10. Together, these results highlight a critical role of PDK1 in OL differentiation during postnatal CNS development.


Asunto(s)
Diferenciación Celular/genética , Vaina de Mielina/metabolismo , Células Precursoras de Oligodendrocitos/metabolismo , Oligodendroglía/metabolismo , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/genética , Factores de Transcripción SOXE/genética , Sustancia Blanca/metabolismo , Animales , Línea Celular , Linaje de la Célula , Regulación hacia Abajo , Ratones , Ratones Noqueados , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/antagonistas & inhibidores , Factores de Transcripción SOXE/metabolismo , Serina-Treonina Quinasas TOR/metabolismo
12.
Virus Genes ; 56(1): 58-66, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31802380

RESUMEN

Canine distemper virus (CDV) causes a highly contagious disease in a wide range of carnivores. The hemagglutinin (H) protein of viruses shows the highest variability and plays an important role in modulation of viral antigenicity, virulence, and receptor recognition. Since 2012, canine distemper (CD) outbreaks in fur-bearing animals (minks, foxes, raccoon dogs) caused by CDV variants with I542N and Y549H substitutions in the H protein have been frequently reported in China. To characterize the molecular evolutionary dynamics and epidemiological dynamics of CDV, 235 H gene sequences of CDV wild-type strains collected from 22 countries between 1975 and 2015, including 44 strains predominant in fur-bearing animals in China, were analyzed. The phylogenetic relationships and evolutionary rates of the CDV strains were determined by Bayesian phylogenetics. The CDV strains clustered into distinct geographic genotypes, irrespective of the species of isolation. All the variant strains formed a distinct monophyletic cluster and belonged to the F sub-genotype within the Asia-1 genotype-currently the predominant sub-genotype in fur-bearing animals in China. Evolutionary analysis suggested that the variant strains originated in 2006. Furthermore, the selection pressure analysis revealed that the Y549H substitution was under positive selection pressure for adaptation toward the fur-bearing animals. The residue at position 549 also showed structural interaction with the V domain of the mink signaling lymphocyte-activation molecule (SLAM) receptor based on the homology modeling of the H-SLAM complex. Our results suggested that the Y549H substitution contributed to the molecular adaptation of CDV variants in the fur-bearing animals during the viral evolutionary phase in China.


Asunto(s)
Sustitución de Aminoácidos , Virus del Moquillo Canino/genética , Moquillo/virología , Zorros/virología , Hemaglutininas Virales/genética , Visón/virología , Perros Mapache/virología , Secuencia de Aminoácidos , Animales , Animales Salvajes/virología , China , Virus del Moquillo Canino/clasificación , Virus del Moquillo Canino/aislamiento & purificación , Virus del Moquillo Canino/metabolismo , Perros , Evolución Molecular , Hemaglutininas Virales/química , Filogenia , Selección Genética
13.
Angew Chem Int Ed Engl ; 59(31): 12938-12943, 2020 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-32329941

RESUMEN

The stability of luminescent materials is a key factor for the practical application in white light-emitting diodes (LEDs). Poor chemical stability of narrow-band green-emitting RbLi(Li3 SiO4 )2 :Eu2+ (RLSO:Eu2+ ) phosphor hinders their further commercialization even if they have excellent stability against thermal quenching. Herein, we propose an efficient protection scheme by combining the surface coating of amorphous Al2 O3 and hydrophobic modification by octadecyltrimethoxysilane (ODTMS) to construct the moisture-resistant dual-shelled RLSO:Eu2+ @Al2 O3 @ODTMS composite. The growth mechanisms of both the Al2 O3 inorganic layer and the silane organic layer on the phosphor surface are investigated. The results remarkably improve the water-stability of this narrow-band green emitter. The evaluation of the white LED by employing this composite as the green component demonstrates that RLSO:Eu2+ @Al2 O3 @ODTMS is a promising candidate for the high-performance display backlights, and this dual-shelled strategy provides an alternative method to improve the moisture-resistant property of humidity-sensitive phosphors.

14.
Chemistry ; 25(12): 2935-2948, 2019 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-30264533

RESUMEN

Converting light hydrocarbons such as methane, ethane, propane, and cyclohexane into value-added chemicals and fuel products by means of direct C-H functionalization is an attractive method in the petrochemical industry. As they emerge as a relatively new class of porous solid materials, metal-organic frameworks (MOFs) are appealing as single-site heterogeneous catalysts or catalytic supports for C-H bond activation. In contrast to the traditional microporous and mesoporous materials, MOFs feature high porosity, functional tunability, and molecular-level characterization for the study of structure-property relationships. These virtues make MOFs ideal platforms to develop catalysts for C-H activation with high catalytic activity, selectivity, and recyclability under relatively mild reaction conditions. This review highlights the research aimed at the implementation of MOFs as single-site heterogeneous catalysts for C-H bond activation. It provides insight into the rational design and synthesis of three types of stable MOF catalysts for C-H bond activation, that is, i) metal nodes as catalytic sites, ii) the incorporation of catalytic sites into organic struts, and iii) the incorporation of catalytically active guest species into pores of MOFs. Here, the rational design and synthesis of MOF catalysts that lead to the distinct catalytic property for C-H bond activation are discussed along with the post-synthesis of MOFs, intriguing functions with MOF catalysts, and microenvironments that lead to the distinct catalytic properties of MOF catalysts.

15.
BMC Neurol ; 19(1): 30, 2019 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-30791893

RESUMEN

BACKGROUND: Posterior reversible encephalopathy syndrome (PRES) is a complication that occurs during various diseases' treatment. Imaging examination is the gold standard for diagnosis. PRES frequently occurrence in patients with hematological malignancies results in poorer prognosis and higher mortality. We aim to establish a practical and operable scale for early prediction, assessment of the severity of the Posterior Reversible Encephalopathy Syndrome, and timely intervention for better prognosis. METHODS: The scale designed by reviewing the literature and by referring to clinical practice. We assessed the reliability and validity of the scale. Scale-based assessment of children undergoing chemotherapy for acute lymphoblastic leukemia conducted as early warning and intervention for those who may have PRES. RESULTS: Establishment of Posterior Reversible Encephalopathy Syndrome early warning scoring (PEWS) scale included three parts, as follows: (1) risk factors, including underlying disease, hypertension, Infection, and drug toxicity; (2) clinical features, including high cranial pressure, visual symptoms, seizure, and disturbance of consciousness; and (3) EEG features, including slow wave and epileptiform discharges. Utility assessment of PEWS scale showed that in 57 patients with acute lymphoblastic leukemia, 54 scored less than 10 and none of them detected as PRES. The other two had scores of 12 and 13 both diagnosed with PRES by brain MRI scan. CONCLUSIONS: PEWS scale can predict PRES early. PRES was highly suspected when the score was 10 points and more. Thus, prophylactic intervention can give to improve the prognosis of PRES.


Asunto(s)
Diagnóstico Precoz , Síndrome de Leucoencefalopatía Posterior/diagnóstico , Adolescente , Niño , Preescolar , Electroencefalografía , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Reproducibilidad de los Resultados , Factores de Riesgo
17.
Chemistry ; 24(6): 1416-1424, 2018 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-29105862

RESUMEN

One-step selective benzene acylation-Nazarov cyclization is an attractive, yet challenging method for the synthesis of the benzocyclopentanone skeleton, which is key intermediate of many natural products. Herein, two metal-cluster-based metal-organic frameworks (MCOFs) {(H3 O)2 [Co4 (pbcd)2 (µ3 -OH)2 ]⋅CH3 CH2 OH⋅4 H2 O}n (1; pbcd=9,9'-(propan-1,3-diyl)bis(9H-carbazole-3,6-dicarboxylic acid) and {[Co5.25 (mcd)2 (HCO2 )(µ2 -O)0.5 (µ3 -OH)0.5 (H2 O)4 ]⋅6 H2 O⋅5 DMF}n (2; mcd=9,9'-methylenebis(9H-carbazole-3,6-dicarboxylic acid) were developed to catalyze a tandem Nazarov cyclization reaction of 1,3-dimethoxybenzene with α,ß-unsaturated carboxylic acids for the synthesis of cyclopentenone[b]benzenes. MCOFs 1 and 2, which were constructed from tetranuclear CoII cluster [Co4 (µ3 -OH)2 ] and hexanuclear CoII cluster [Co6 (HCO2 )(µ2 -O)(µ3 -OH)], respectively, exhibit high catalytic activity arising not only from their suitable channel size and accessible catalytic sites, but also because of their high density of Lewis acidic sites within the frameworks and the synergic activity among CoII ions. In contrast, {[Co2 (pbcd)(bpe)]⋅2 H2 O⋅2 DMF}n (3; bpe=1,2-bis(pyridin-4-yl)ethane) containing binuclear CoII and having large pore windows is a highly selective catalyst for obtaining exclusively the acylation products. Easy product separation, simple reaction procedures, and catalyst recycling make the catalyst system attractive. This work highlights the synergistic effect among ions of MCOFs in interacting with substrates in a sequential or cooperative manner to achieve tandem catalysis.

18.
Inorg Chem ; 57(16): 10224-10231, 2018 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-30063336

RESUMEN

A rare example of SC-SC triggered by Cu2+ heterogeneous oxidation was demonstrated in a Fe(II)-based MOF {[FeII3(L)2(H2O)6]·3H2O} n (1), which occurred a slow conversion into an oxidized MOF 2 ({[FeIII3(L)2(H2O)6]·3(OH)} n) with retention of single crystallinity. The FeII → FeIII progress of the reaction oxidation was proved by single crystal XRD, PXRD, XPS, 57Fe Mössbauer spectroscopy, and UV-vis. We used 1 and 2 as catalysts to catalyze the tandem Nazarov cyclization, and the results show that acylation products were only harvested when 1 was a catalyst, while the oxidized transformer 2 lead mainly to the formation of cyclization products under identical conditions. Through the test of different substrates, 2 can be a good heterogeneous catalyst candidate for the formation of cyclopentenone[ b] benzenes. This work provides a new way to design efficient and hard-synthesized heterogeneous catalyst materials.

19.
Dis Colon Rectum ; 60(11): 1175-1183, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28991082

RESUMEN

BACKGROUND: There is little information about the prognostic value of a microscopically positive distal margin in patients who have rectal cancer. OBJECTIVE: We aimed to investigate the influence of a distal margin of ≤1 mm on oncologic outcomes after sphincter-preserving resection for rectal cancer. DESIGN: This is a retrospective cohort study. SETTINGS: The study was conducted at 2 hospitals. PATIENTS: A total of 6574 patients underwent anterior resection for rectal cancer from January 1999 to December 2014; 97 (1.5%) patients with a distal margin of ≤1 mm were included in this study. For comparative analyses, patients were matched with 194 patients with a negative distal margin (>1 mm) according to sex, age, BMI, ASA score, neoadjuvant treatment, tumor location, and stage. MAIN OUTCOME MEASURES: The oncologic outcomes of the 2 groups were compared. RESULTS: Perineural and lymphovascular invasion rates were significantly higher in patients with a positive distal margin (54.6% vs 28.9%; 67.0% vs 42.8%; both p < 0.001) compared with to patients with negative distal margin. Comparison between microscopically positive and negative distal margin showed worse oncologic outcomes in patients with a microscopically positive distal margin, including 5-year local recurrence rate (24.1% vs 12.0%, p = 0.005); 5-year distant recurrence rate (35.5% vs 20.2%, p = 0.011); 5-year disease-free survival (45.5% vs 69.5%, p < 0.001); and 5-year OS (69.2% vs 79.7%, p = 0.004). Among the 97 patients with a microscopically positive distal margin, the 5-year disease-free survival rate was higher in patients who received adjuvant therapy (52.0% vs 30.7%, p = 0.089). LIMITATIONS: This is a retrospective study; bias may exist. CONCLUSIONS: A distal margin of 1 mm is associated with worse oncologic results. Our data indicate the importance of achieving a clear distal margin in the surgical treatment of rectal cancer. Adjuvant therapy should be used in these patients to reduce recurrence. See Video Abstract at http://links.lww.com/DCR/A408.


Asunto(s)
Adenocarcinoma/cirugía , Márgenes de Escisión , Recurrencia Local de Neoplasia/etiología , Neoplasias del Recto/cirugía , Recto/cirugía , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/prevención & control , Pronóstico , Neoplasias del Recto/mortalidad , Neoplasias del Recto/patología , Recto/patología , Estudios Retrospectivos , Análisis de Supervivencia
20.
Inorg Chem ; 56(21): 13329-13336, 2017 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-29035050

RESUMEN

To develop coordination polymers (CPs) as catalysts to selectively catalyze the reaction of C-H bond activation of arylalkanes to their homologous ketones, three new Cu(I)-based coordination polymers (CuI-CPs) [CuI(aas-TPB)]n (1), [CuBr(ass-TPB)CH3CN]n (2), and {[Cu(ass-TPB)]Cl}n (3) (TPB = N,N,N-tris(3-pyridinyl)-1,3,5-benzenetricarboxamide) were synthesized. Structural variations from a herringbone fashion one-dimensional framework of 1 to a two-dimensional framework of 2 containing a 48-membered macrocycle and a cationic three-dimensional framework of 3 filled with Cl- anions were observed arising from the different halogen ions (I-, Br-, and Cl-). 1-3 were used as the green heterogeneous catalysts to catalyze direct C-H bond activation reactions of arylalkanes to ketones under mild reaction conditions with water as solvent. Handy product separation, convenient reaction procedures, and recyclability of these catalysts make the catalytic system fascinating. Moreover, the CuI-CPs performed the reaction with high regioselectivity due to the unique spatial confinement effect of CPs.

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