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1.
Bioorg Med Chem Lett ; 105: 129752, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38631541

RESUMEN

The misfolding and aggregation of α-Syn play a pivotal role in connecting diverse pathological pathways in Parkinson's disease (PD). Preserving α-Syn proteostasis and functionality by inhibiting its aggregation or disaggregating existing aggregates using suitable inhibitors represents a promising strategy for PD prevention and treatment. In this study, a series of benzothiazole-polyphenol hybrids was designed and synthesized. Three identified compounds exhibited notable inhibitory activities against α-Syn aggregation in vitro, with IC50 values in the low micromolar range. These inhibitors demonstrated sustained inhibitory effects throughout the entire aggregation process, stabilizing α-Syn proteostasis conformation. Moreover, the compounds effectively disintegrated preformed α-Syn oligomers and fibers, potentially by binding to specific domains within the fibers, inducing fibril instability, collapse, and ultimately resulting in smaller-sized aggregates and monomers. These findings offer valuable insights into the therapeutic potential of polyphenol hybrids with 2-conjugated benzothiazole targeting α-Syn aggregation in the treatment of PD.


Asunto(s)
Benzotiazoles , Polifenoles , Agregado de Proteínas , alfa-Sinucleína , Benzotiazoles/química , Benzotiazoles/farmacología , Benzotiazoles/síntesis química , alfa-Sinucleína/antagonistas & inhibidores , alfa-Sinucleína/metabolismo , Polifenoles/química , Polifenoles/farmacología , Polifenoles/síntesis química , Humanos , Agregado de Proteínas/efectos de los fármacos , Estructura Molecular , Relación Estructura-Actividad , Relación Dosis-Respuesta a Droga , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo
2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(2): 434-438, 2024 Apr.
Artículo en Chino | MEDLINE | ID: mdl-38660848

RESUMEN

OBJECTIVE: To detect the expression of L-type amino acid transporter 1 (LAT1) in non-Hodgkin's lymphoma (NHL) tissues, and analyze its effect on clinicopathological characteristics and prognosis of patients. METHODS: A total of 92 NHL patients who were treated in our hospital from January 2017 to April 2019 were collected. The expression of LAT1 in NHL tissue was detected by immunohistochemistry and compared between patients with different pathological features (including sex, Ann Arbor stage, extranodal infiltration, Ki-67). The risk factors affecting mortality were analyzed using univariate and multivariate Cox proportional hazards regression. Receiver operating characteristic (ROC) curve was used to detect the predictive value of percentage of LAT1-positive cells in NHL tissue for patient mortality, and analyzing the effect of percentage of LAT1-positive cells on survival rate. RESULTS: LAT1 was positively expressed in NHL tissue. The high expression rate of LAT1 in Ann Arbor stage III and IV groups were higher than that in Ann Arbor stage I group, that in extranodal infiltration group was higher than non-extranodal infiltration group, and that in Ki-67 positive expression group was higher than Ki-67 negative expression group (all P < 0.05). The remission rate after 3 courses of treatment in high-LAT1 expression group was 70.7%, which was lower than 91.2% in low-LAT1 expression group (P < 0.05). Ann Arbor stage III and IV, extranodal invasion, Ki-67 positive expression and increased expression of LAT1 (LAT1-positive cell percentage score ≥2) were risk factors for mortality. The cut-off value of percentage of LAT1-positive cells for predicting NHL death was 45.6%, and the area under the ROC curve was 0.905 (95%CI: 0.897-0.924). The 3-year survival rate of high-LAT1 level group (the percentage of LAT1-positive cells≥45.6%) was 50.00%, which was lower than 78.26% of low-LAT1 level group (P < 0.05). CONCLUSION: The expression level of LAT1 in NHL tissue increases, which affects Ann Arbor stage and extranodal infiltration of patients. LAT1 is a risk factor for death.


Asunto(s)
Transportador de Aminoácidos Neutros Grandes 1 , Linfoma no Hodgkin , Humanos , Transportador de Aminoácidos Neutros Grandes 1/metabolismo , Linfoma no Hodgkin/metabolismo , Linfoma no Hodgkin/patología , Pronóstico , Masculino , Femenino , Factores de Riesgo , Tasa de Supervivencia , Estadificación de Neoplasias , Curva ROC , Persona de Mediana Edad
3.
Eur J Med Chem ; 268: 116198, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38368711

RESUMEN

α-Syn fibers, the primary cause and central element of Lewy bodies (LB), play a pivotal role in the development of Parkinson's disease (PD). This research aims to identify more potent inhibitors of α-Syn aggregation. A series of N-aryl-3-aryl-pyrazole-5-carboxamide derivatives were designed and synthesized for this purpose. Among them, four candidate compounds, combining pyrazole and polyphenol blocks, were identified through screening, demonstrating good inhibitory effects with IC50 values in the low micromolar range (1.25-4.29 µM). Two candidates exhibited high permeability through the blood-brain barrier. Mechanistic studies using various methods revealed that the candidates preferentially bind to the aggregation-prone domains-proNAC or NAC domains of α-Syn. This binding hinders the conformational transition from random coil/α-helix to ß-sheet, preserving α-Syn proteostasis. As a result, it interferes with α-Syn nuclei formation, prolongs the lag phase, decelerates the elongation phase, and ultimately impedes the formation of α-Syn fibrils. Additionally, the candidates demonstrated promising results in the disaggregation of preformed α-Syn fibers, potentially by binding to specific sites near the ß-sheet domain within fibers. This reduces fiber stability, causing rapid collapse and yielding smaller aggregates and monomers. Crucially, the candidate compounds exhibited significant inhibitory efficacy against α-Syn aggregation within nerve cells with low cytotoxicity. This resulted in a notable inhibition of the formation of LB-like α-Syn inclusions. These compounds show considerable promise as potential therapeutic agents for the prevention and treatment of PD.


Asunto(s)
Enfermedad de Parkinson , alfa-Sinucleína , Humanos , alfa-Sinucleína/metabolismo , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo , Neuronas/metabolismo , Transporte Biológico
4.
Bioorg Med Chem Lett ; 99: 129618, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38219887

RESUMEN

This study focuses on the discovery of new potential drugs for treating PD by targeting the aggregation of α-Syn. A series of hybrids combining Coumarin and phenolic acid were designed and synthesized. Four particularly promising compounds were identified, showing strong inhibitory effects with IC50 values ranging from low micromolar to submicromolar concentrations, as low as 0.63 µM. These compounds exhibited a higher binding affinity to α-Syn residues and effectively hindered the entire aggregation process, maintaining the proteostasis conformation of α-Syn and preventing the formation of ß-sheet aggregates. This approach holds significant promise for PD prevention. Additionally, these candidate compounds demonstrated the ability to break down preformed α-Syn oligomers and fibrils, resulting in the formation of smaller aggregates and monomers. Moreover, the candidate compounds showed impressive effectiveness in inhibiting α-Syn aggregation within nerve cells, thereby reducing the likelihood of α-Syn inclusion formation resembling Lewy bodies, which highlights their potential for treating PD.


Asunto(s)
Neuronas , alfa-Sinucleína , alfa-Sinucleína/metabolismo , Unión Proteica , Neuronas/metabolismo , Cumarinas/farmacología
5.
Angew Chem Int Ed Engl ; 63(11): e202319685, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38151975

RESUMEN

Glycerol is a byproduct of biodiesel production. Selective photoelectrochemical oxidation of glycerol to high value-added chemicals offers an economical and sustainable approach to transform renewable feedstock as well as store green energy at the same time. In this work, we synthesized monoclinic WO3 nanosheets with exposed (002) facets, which could selectively oxidize glycerol to glyceric acid (GLYA) with a photocurrent density of 1.7 mA cm-2 , a 73 % GLYA selectivity and a 39 % GLYA Faradaic efficiency at 0.9 V vs. reversible hydrogen electrode (RHE) under AM 1.5G illumination (100 mW cm-2 ). Compared to (200) facets exposed WO3 , a combination of experiments and theoretical calculations indicates that the superior performance of selective glycerol oxidation mainly originates from the better charge separation and prolonged carrier lifetime resulted from the plenty of surface trapping states, lower energy barrier of the glycerol-to-GLYA reaction pathway, more abundant active sites and stronger oxidative ability of photogenerated holes on the (002) facets exposed WO3 . Our findings show great potential to significantly contribute to the sustainable and environmentally friendly chemical processes via designing high performance photoelectrochemical cell via facet engineering for renewable feedstock transformation.

6.
Bioorg Med Chem Lett ; 97: 129564, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-38000482

RESUMEN

The aggregation of α-Syn is a pivotal mechanism in Parkinson's disease (PD). Effectively maintaining α-Syn proteostasis involves both inhibiting its aggregation and promoting disaggregation. In this study, we developed a series of aromatic amide derivatives based on Rhein. Two of these compounds, 4,5-dihydroxy-N-(3-hydroxyphenyl)-9,10-dioxo-9,10-dihydroanthracene-2-carboxamide (a5) and 4,5-dihydroxy-N-(2-hydroxy-4-chlorophenyl)-9,10-dioxo-9,10-dihydroanthracene-2-carboxamide (a8), exhibited good binding affinities to α-Syn residues, demonstrating promising inhibitory activity against α-Syn aggregation in vitro, with low IC50 values (1.35 and 1.08 µM, respectivly). These inhibitors acted throughout the entire aggregation process by stabilizing α-Syn's conformation and preventing the formation of ß-sheet aggregates. They also effectively disassembled preformed α-Syn oligomers and fibrils. Preliminary mechanistic insights indicated that they bound to the specific domain within fibrils, inducing fibril instability, collapse, and the formation of smaller aggregates and monomeric α-Syn units. This research underscores the therapeutic potential of Rhein's aromatic amides in targeting α-Syn aggregation for PD treatment and suggests broader applications in managing and preventing neurodegenerative diseases.


Asunto(s)
Antracenos , Enfermedad de Parkinson , Humanos , alfa-Sinucleína , Antraquinonas/farmacología , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/prevención & control , Enfermedad de Parkinson/metabolismo , Antracenos/química , Antracenos/farmacología
7.
Bioorg Med Chem ; 96: 117529, 2023 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-37976808

RESUMEN

This study focuses on the misfolding and aggregation of α-Syn as a central mechanism linking various pathological processes in PD. Maintaining α-Syn proteostasis through suitable inhibitors emerges as an effective approach to prevent PD. A more efficient strategy for PD treatment involves disintegrating neurotoxic oligomers and fibrils into normal functional α-Syn using inhibitors. To this end, a series of 4-arylidene curcumin derivatives were synthesized with a sheet-like conjugated skeleton and higher binding energies with α-Syn residues. Among these derivatives, three candidate compounds exhibited promising α-Syn aggregation inhibitory activities in vitro, with IC50 values as low as 0.61 µM. The inhibitory action extended throughout the entire aggregation process, stabilizing α-Syn proteostasis conformation and preventing ß-sheets aggregation. Furthermore, the candidate compounds demonstrated effective disintegration capabilities against preformed α-Syn oligomers and fibrils. Initial mechanistic investigations indicated that the inhibitors may bind to a specific domain within the fibril, inducing fibril instability and subsequent collapse. This process resulted in the formation of a complex system of aggregates with smaller sizes and monomers. Overall, these findings provide valuable insights into the potential of 4-arylidene curcumin derivatives as therapeutic agents for targeting α-Syn aggregation in PD treatment.


Asunto(s)
Curcumina , alfa-Sinucleína , alfa-Sinucleína/metabolismo , Curcumina/farmacología , Unión Proteica , Amiloide/metabolismo , Agregado de Proteínas
8.
World J Stem Cells ; 15(6): 589-606, 2023 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-37424952

RESUMEN

BACKGROUND: Accumulating evidence suggests that the maxillary process, to which cranial crest cells migrate, is essential to tooth development. Emerging studies indicate that Cd271 plays an essential role in odontogenesis. However, the underlying mechanisms have yet to be elucidated. AIM: To establish the functionally heterogeneous population in the maxillary process, elucidate the effects of Cd271 deficiency on gene expression differences. METHODS: p75NTR knockout (Cd271-/-) mice (from American Jackson laboratory) were used to collect the maxillofacial process tissue of p75NTR knockout mice, and the wild-type maxillofacial process of the same pregnant mouse wild was used as control. After single cell suspension, the cDNA was prepared by loading the single cell suspension into the 10x Genomics Chromium system to be sequenced by NovaSeq6000 sequencing system. Finally, the sequencing data in Fastq format were obtained. The FastQC software is used to evaluate the quality of data and CellRanger analyzed the data. The gene expression matrix is read by R software, and Seurat is used to control and standardize the data, reduce the dimension and cluster. We search for marker genes for subgroup annotation by consulting literature and database; explore the effect of p75NTR knockout on mesenchymal stem cells (MSCs) gene expression and cell proportion by cell subgrouping, differential gene analysis, enrichment analysis and protein-protein interaction network analysis; understand the interaction between MSCs cells and the differentiation trajectory and gene change characteristics of p75NTR knockout MSCs by cell communication analysis and pseudo-time analysis. Last we verified the findings single cell sequencing in vitro. RESULTS: We identified 21 cell clusters, and we re-clustered these into three subclusters. Importantly, we revealed the cell-cell communication networks between clusters. We clarified that Cd271 was significantly associated with the regulation of mineralization. CONCLUSION: This study provides comprehensive mechanistic insights into the maxillary- process-derived MSCs and demonstrates that Cd271 is significantly associated with the odontogenesis in mesenchymal populations.

9.
BMC Vet Res ; 19(1): 81, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37391757

RESUMEN

The objective of this study was to synthesize and characterize pharmaceutical characteristics of florfenicol sustained-release granules (FSRGs) in vitro and in vivo. FSRGs were synthesized using monostearate, polyethylene glycol 4000 and starch. In vitro dissolution profiles were studied using the rotating basket method in pH 1.2 HCl solution and pH 4.3 acetate buffer. Twenty-four male healthy Landrace×Yorkshire pigs were equally divided into three groups and administered a 20 mg/kg i.v bolus of florfenicol solution and dosed orally with FSRGs in the fasting and fed states. The Higuchi model was the best fit for the drug release profile in pH 1.2 and pH 4.3 media, and the mechanism of drug dissolution was governed by both diffusion and dissolution. We established a level A in vitro - in vivo correlation for FSRGs and the in vivo profile of the FSRGs can be estimated by the in vitro drug release.


Asunto(s)
Proyectos de Investigación , Tianfenicol , Masculino , Animales , Porcinos , Correlación de Datos , Preparaciones de Acción Retardada
10.
Toxicology ; 489: 153497, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-37011868

RESUMEN

Beta-cypermethrin (ß-CYP) is a universally used pyrethroid pesticide with adverse effects on human health. ß-CYP may impair endometrial remodeling in mice; however, the mechanism remains largely unknown. Endometrial remodeling plays a vital role in embryonic development and the maintenance of pregnancy. Therefore, we explored the mechanism by which peri-implantation ß-CYP administration reduces uterine remodeling in pregnant mice. The C57BL/6 J pregnant mice were administered a dose of 20 mg/kg.bw. d ß-CYP via oral gavage once daily from day 1 of gestation (GD1) to GD7. Molecular markers of endometrial remodeling, stromal cell proliferation, cell cycle regulation, and the PI3K/Akt/mTOR signaling pathway were evaluated in the decidual tissue of the uterus on GD7. An in vivo pseudopregnancy mouse model, a pregnant mouse model treated with an mTOR activator and an mTOR inhibitor and an in vitro decidualization model of mouse endometrial stromal cells were used to confirm ß-CYP-induced defective endometrial remodeling and the key molecules expression of PI3K/Akt/mTOR signaling pathway. The results showed that ß-CYP decreased the expression of the endometrial remodeling markers MMP9 and LIF in the uterine decidua. Peri-implantation ß-CYP treatment markedly downregulated the expression of endometrial proliferation markers PCNA and Ki67 and decreased decidua thickness. Correspondingly, peri-implantation ß-CYP exposure upregulated the expression of FOXO1, P57 and p-4E-BP1 in the decidua. Further experiments showed ß-CYP significantly inhibited key molecules in the PI3K/Akt/mTOR pathway: PI3K, p-Akt/Akt, p-mTOR, and p-P70S6K in the uterine decidua. Additional experiments showed that aberrant endometrial remodeling induced by ß-CYP was aggravated by rapamycin (an mTOR inhibitor) and partially reversed by MHY1485 (an mTOR agonist). In summary, our results indicated that a reduction in the PI3K/Akt/mTOR pathway may enhance defective endometrial remodeling by downregulating the proliferation and differentiation of endometrial stromal cells in early pregnant mice exposed to ß-CYP. Our study elucidates the mechanism of defective endometrial remodeling induced by peri-implantation ß-CYP exposure.


Asunto(s)
Plaguicidas , Piretrinas , Embarazo , Femenino , Ratones , Humanos , Animales , Decidua/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Plaguicidas/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Ratones Endogámicos C57BL , Endometrio , Implantación del Embrión , Serina-Treonina Quinasas TOR/metabolismo , Piretrinas/toxicidad , Células del Estroma
11.
Eur J Med Chem ; 249: 115122, 2023 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-36680987

RESUMEN

Neurotoxic α-Syn fibers, the main components of Lewy bodies, play a key role in the development of PD characterized by a progressive loss of dopaminergic neurons. Here, we designed and synthesized the hybrids of polyphenolic/quinone acids. The candidate compounds showed high α-Syn aggregation inhibitory activities in vitro with IC50 down to 1.6 µM. The inhibition went through the aggregation process by stabilizing the conformation of α-Syn proteostasis and preventing ß-sheets aggregation, especially in the lag phase. Furthermore, the candidate drugs could disintegrate the preformed varisized aggregates into pony-size aggregates and functional monomers and continually inhibit the re-aggregation. The activities of anti-aggregation and aggregates depolymerization result in the reduction of inclusions in neuron cells. The candidate drugs also show high anti-oxidation and low cytotoxicity. They finally repair the damaged neurons in 6-OHDA-lesioned C57 mice and significantly improve PD-like symptoms of the PD model mice. The hybrids are promising molecules for PD prevention and therapy.© 2022 Elsevier Masson SAS. All rights reserved.


Asunto(s)
Enfermedad de Parkinson , Ratones , Animales , Caballos , Enfermedad de Parkinson/tratamiento farmacológico , alfa-Sinucleína , Cuerpos de Lewy , Neuronas , Benzoquinonas
12.
ACS Omega ; 7(25): 21608-21614, 2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35785280

RESUMEN

This method afforded aromatic carbonyl compounds under TBHP via selective oxidative cleavage of the C-C bond in α,ß-epoxy ketones. Aromatic acid came from the aroyl section, and aromatic aldehyde came from the other aromatic group. TBHP acted as a free radical initiator and oxidant. The reaction within the solvent went through a ring-opening addition, cleavage of the C-C bond in the ethylene oxide section, and oxidation, affording the target compounds in moderate to good yields. The HPLC yield of aromatic aldehyde was up to 91%. The HPLC yield of aromatic acid was up to 99%. The reaction under solvent-free conditions gave two kinds of aromatic acids coming from different moieties of α,ß-epoxy ketone via the further oxidation of aromatic aldehyde. The substituent effect was discussed, and the reaction mechanism was proposed. This method allowed the reaction to occur in a simple system metal-free.

13.
Eur J Med Chem ; 239: 114529, 2022 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-35728509

RESUMEN

α-Syn fibrils, which are neurotoxic, play a key role in the development of PD. Maintaining α-Syn proteostasis by suitable molecule ligands is an effective approach to prevent aggregation. Disintegrating the existed oligomers and fibrils into individual α-Syn by small molecular compounds is a more efficient way to treat PD. This work designed and synthesized two series of bis-chalcone polyphenol compounds, which possess a sheet-like conjugated skeleton with stronger H-bonding, π-stacking, and hydrophobic interaction with α-Syn protein residues. Some compounds have shown high α-Syn aggregation inhibitory activities in vitro with IC50 down to 0.64 µM. The inhibition goes throughout the aggregation process from the lag to the stationary phase by stabilizing α-Syn proteostasis conformation and preventing ß-sheets aggregation, especially in the lag phase. In addition, the inhibitors present good disintegration abilities against the existed α-Syn oligomers and fibrils. The preliminary mechanism studies suggest that the inhibitors could quickly and randomly bind to the specific site closed to the ß-sheet domain in the fibril, resulting in unstable and collapse of the protein fibril and yielding a complex system with aggregates of different sizes and monomers. The inhibitors, which could penetrate the blood-brain barrier, are expected to develop into the drug candidates for PD targeting α-Syn aggregation.


Asunto(s)
Chalcona , Chalconas , Chalcona/farmacología , Ligandos , Polifenoles/farmacología , Agregado de Proteínas , alfa-Sinucleína/metabolismo
14.
Bioorg Med Chem ; 66: 116818, 2022 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-35584603

RESUMEN

The misfolding and aggregation of α-Syn are the central mechanism linking and facilitating the other pathological mechanisms of PD. Maintaining α-Syn proteostasis by suitable inhibitors is an effective means to prevent PD. Disintegrating the neurotoxic oligomers and fibrils into the normal functional α-Syn by inhibitors is a more efficient way for PD treatment. This work synthesized two series hybrids of polyphenolic acids and xanthone. The hybrids possess a sheet-like conjugated skeleton and higher binding energies with α-Syn residues. Some compounds present well α-Syn aggregation inhibitory activities in vitro (IC50 down to 2.58 µM). The inhibitory action goes throughout the aggregation process from lag to the stationary phase by stabilizing α-Syn proteostasis conformation and preventing ß-sheets aggregation. The candidate compounds with appropriate LogP values (2.02-3.11) present good disintegration abilities against the existed α-Syn oligomers and fibrils. The preliminary mechanism studies suggest that the inhibitors could quickly and randomly bind to the specific site closed to the ß-sheet domain in the fibril, resulting in unstable and collapse of the protein fibril, yielding a complex system with aggregates of different sizes and monomers.


Asunto(s)
Enfermedad de Parkinson , Xantonas , Amiloide/metabolismo , Humanos , Enfermedad de Parkinson/metabolismo , Agregado de Proteínas , Xantonas/farmacología , alfa-Sinucleína/metabolismo
15.
BMC Plant Biol ; 22(1): 113, 2022 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-35279080

RESUMEN

BACKGROUND: Many seed plants produce winged diaspores that use wind to disperse their seeds. The morphology of these diaspores is directly related to the seed dispersal potential. The majority of winged diaspores have flat wings and only seeds; however, some angiosperms, such as Firmiana produce winged fruit with a different morphology, whose seed dispersal mechanisms are not yet fully understood. In this study, we observed the fruit development of F. simplex and determined the morphological characteristics of mature fruit and their effects on the flight performance of the fruit. RESULTS: We found that the pericarp of F. simplex dehisced early and continued to unfold and expand during fruit development until ripening, finally formed a spoon-shaped wing with multiple alternate seeds on each edge. The wing caused mature fruit to spin stably during descent to provide a low terminal velocity, which was correlated with the wing loading and the distribution of seeds on the pericarp. When the curvature distribution of the pericarp surface substantially changed, the aerodynamic characteristics of fruit during descent altered, resulting in the inability of the fruit to spin. CONCLUSIONS: Our results suggest that the curved shape and alternate seed distribution are necessary for the winged diaspore of F. simplex to stabilize spinning during wind dispersal. These unique morphological characteristics are related to the early cracking of fruits during development, which may be an adaptation for the wind dispersal of seeds.


Asunto(s)
Frutas/anatomía & histología , Frutas/crecimiento & desarrollo , Malvaceae/anatomía & histología , Malvaceae/crecimiento & desarrollo , Dispersión de Semillas , Semillas/anatomía & histología , Semillas/crecimiento & desarrollo , China , Fenotipo , Viento
16.
World J Clin Cases ; 9(4): 970-975, 2021 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-33585646

RESUMEN

BACKGROUND: Aortic dissection (AD) is an emergent and life-threatening disorder, and its in-hospital mortality was reported to be as high as 24.4%-27.4%. AD can mimic other more common disorders, especially acute myocardial infarction (AMI), in terms of both symptoms and electrocardiogram changes. Reperfusion for patients with AD may result in catastrophic outcomes. Increased awareness of AD can be helpful for early diagnosis, especially among younger patients. CASE SUMMARY: We report a 28-year-old man with acute left side chest pain without cardiovascular risk factors. He was diagnosed with acute inferior ST-segment elevation myocardial infarction (STEMI), which, based on illness history, physical examination, and intraoperative findings, was eventually determined to be type A AD caused by Marfan syndrome. Emergent coronary angiography revealed the anomalous origin of the right coronary artery as well as eccentric stenosis of the proximal segment. Subsequently, computed tomography angiography (CTA) showed intramural thrombosis of the ascending aorta. Finally, the patient was transferred to the cardiovascular surgery department for a Bentall operation. He was discharged 13 d after the operation, and aortic CTA proved a full recovery at the 2-year follow-up. CONCLUSION: It is essential and challenging to differentiate AD from AMI. Type A AD should be the primary consideration in younger STEMI patients without cardiovascular risk factors but with outstanding features of Marfan syndrome.

17.
Ther Clin Risk Manag ; 17: 87-101, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33519206

RESUMEN

PURPOSE: Perioperative anesthetic management may affect long-term outcome after cancer surgery. This study investigated the effect of perioperative glucocorticoids on long-term survival in patients after radical resection for pancreatic cancer. METHODS: In this retrospective cohort study with propensity score-matching, patients who underwent radical resection for pancreatic cancer from January 2005 to December 2016 were recruited. Baseline and perioperative data including use of glucocorticoids for prevention of postoperative nausea and vomiting were collected. Patients were followed up by qualified personnel for cancer recurrence and survival. The primary outcome was the recurrence-free survival. Outcomes were compared before and after propensity matching. The association between perioperative glucocorticoid use and recurrence-free survival was analyzed with multivariable regression models. RESULTS: A total of 215 patients were included in the study; of these, 112 received perioperative glucocorticoids and 103 did not. Patients were followed up for a median of 74.0 months (95% confidence interval [CI] 68.3-79.7). After propensity score-matching, 64 patients remained in each group. The recurrence-free survivals were significantly longer in patients with glucocorticoids than in those without (full cohort: median 12.0 months [95% CI 6.0-28.0] vs 6.9 months [4.2-17.0], P<0.001; matched cohort: median 12.0 months [95% CI 5.8-26.3] vs 8.3 months [4.3-18.2], P=0.015). After correction for confounding factors, perioperative glucocorticoids were significantly associated with prolonged recurrence-free survivals (full cohort: HR 0.66, 95% CI 0.48-0.92, P=0.015; matched cohort: HR 0.54, 95% CI 0.35-0.84, P=0.007). CONCLUSION: Perioperative use of low-dose glucocorticoids is associated with improved recurrence-free survival in patients following radical surgery for pancreatic cancer.

18.
Bioorg Med Chem ; 28(15): 115596, 2020 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32631566

RESUMEN

Gallic acid (GA), a natural phenolic acid, has received numerous attention because of its anti-oxidative, anti-inflammatory, and anti-cancer activity. More importantly, GA can act as an efficient inhibitor of α-Synuclein (α-Syn) aggregation at early stages. Nevertheless, some evidences suggest that GA is unlikely to cross the blood-brain barrier because of its high hydrophilicity. Hence, GA may not be considered as a promising candidate or entering brain and directly affecting the central nervous system. Accordingly, we have designed and synthesized a series of amide derivatives of GA, some of which possess appropriate lipophilicity and hydrophilicity with LogP (2.09-2.79). Meanwhile, these sheet-like conjugated compounds have good π-electron delocalization and high ability of hydrogen-bond formation. Some compounds have shown better in vitro anti-aggregation activities than GA towards α-Syn, with IC50 down to 0.98 µM. The valid modification strategy of GA is considered an efficient way to discover novel inhibitors of α-Syn aggregation.


Asunto(s)
Amidas/química , Ácido Gálico/análogos & derivados , Multimerización de Proteína/efectos de los fármacos , alfa-Sinucleína/metabolismo , Amidas/síntesis química , Diseño de Fármacos , Ácido Gálico/síntesis química , Interacciones Hidrofóbicas e Hidrofílicas , Estructura Molecular , Relación Estructura-Actividad
19.
Bioorg Med Chem ; 27(14): 3089-3096, 2019 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-31196755

RESUMEN

Aggregation of α-synuclein (α-Syn) play a key role in the development of Parkinson Disease (PD). One of the effective approaches is to stabilize the native, monomeric protein with suitable molecule ligands. We have designed and synthesized a series of sheet-like conjugated compounds which possess different skeletons and various heteroatoms in the two blocks located at both ends of linker, which have good π-electron delocalization and high ability of hydrogen-bond formation. They have shown anti-aggregation activities in vitro towards α-Syn with IC50 down to 1.09 µM. The molecule is found binding in parallel to the NACore within NAC domain of α-Syn, interfering aggregation of NAC region within different α-Syn monomer, and further inhibiting or slowing down the formation of α-Syn oligomer nuclei at lag phase. The potential inhibitor obtained by our strategy is considered to be highly efficient to inhibit α-Syn aggregation.


Asunto(s)
Agregado de Proteínas/efectos de los fármacos , alfa-Sinucleína/antagonistas & inhibidores , Humanos
20.
ACS Appl Mater Interfaces ; 11(16): 14986-14996, 2019 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-30945844

RESUMEN

A facile and simple synthetic route is developed to prepare earth-abundant and noble metal-free hybrid photocatalysts, which are composed of graphitic carbon nitride (CN), nickel complex, and NiO x nanoparticles. Bimolecular nucleophilic substitution reaction was employed to attach a nickel complex onto a graphitic CN framework through covalent bonds to support its high loading and dispersion. NiO x nanoparticles were further incorporated into the catalysts to serve as a hole-transporting medium to improve the separation of photogenerated carriers for higher photocatalytic activity. Both yNiL/CN and yNiL/NiO x/CN exhibit superb H2 evolution activity. The optimum H2 evolution rate of the binary photocatalysts yNiL/CN reaches 303.3 µmol·h-1·g-1, whereas that of the ternary photocatalysts yNiL/NiO x/CN reaches 524.1 µmol·h-1·g-1, and the apparent quantum efficiency reaches 1.46% at 450 nm. This finding reveals that coordination of a nickel complex is significant in promoting photocatalytic performance, and the incorporation of NiO x nanoparticles as a hole-transporting medium is beneficial for separation of the photogenerated charge carriers. The novel hybrid system offers a new horizon for designing transition-metal complex-modified graphitic CN as noble metal-free and highly active photocatalysts for efficient visible light-driven hydrogen generation.

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