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1.
Nature ; 633(8028): 90-95, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39169193

RESUMO

Although aromatic rings are common elements in pharmaceutically active compounds, the presence of these motifs brings several liabilities with respect to the developability of a drug1. Nonoptimal potency, metabolic stability, solubility and lipophilicity in pharmaceutical compounds can be improved by replacing aromatic rings with non-aromatic isosteric motifs2. Moreover, whereas aromatic rings are planar and lack three-dimensionality, the binding pockets of most pharmaceutical targets are chiral. Thus, the stereochemical configuration of the isosteric replacements may offer an added opportunity to improve the affinity of derived ligands for target receptors. A notable impediment to this approach is the lack of simple and scalable catalytic enantioselective syntheses of candidate isosteres from readily available precursors. Here we present a previously unknown palladium-catalysed reaction that converts hydrocarbon-derived precursors to chiral boron-containing nortricyclanes and we show that the shape of these nortricyclanes makes them plausible isosteres for meta disubstituted aromatic rings. With chiral catalysts, the Pd-catalysed reaction can be accomplished in an enantioselective fashion and subsequent transformation of the boron group provides access to a broad array of structures. We also show that the incorporation of nortricyclanes into pharmaceutical motifs can result in improved biophysical properties along with stereochemistry-dependent activity. We anticipate that these features, coupled with the simple, inexpensive synthesis of the functionalized nortricyclane scaffold, will render this platform a useful foundation for the assembly of new biologically active agents.

2.
Hum Brain Mapp ; 45(1): e26566, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38224535

RESUMO

Both plasma biomarkers and brain network topology have shown great potential in the early diagnosis of Alzheimer's disease (AD). However, the specific associations between plasma AD biomarkers, structural network topology, and cognition across the AD continuum have yet to be fully elucidated. This retrospective study evaluated participants from the Sino Longitudinal Study of Cognitive Decline cohort between September 2009 and October 2022 with available blood samples or 3.0-T MRI brain scans. Plasma biomarker levels were measured using the Single Molecule Array platform, including ß-amyloid (Aß), phosphorylated tau181 (p-tau181), glial fibrillary acidic protein (GFAP), and neurofilament light chain (NfL). The topological structure of brain white matter was assessed using network efficiency. Trend analyses were carried out to evaluate the alterations of the plasma markers and network efficiency with AD progression. Correlation and mediation analyses were conducted to further explore the relationships among plasma markers, network efficiency, and cognitive performance across the AD continuum. Among the plasma markers, GFAP emerged as the most sensitive marker (linear trend: t = 11.164, p = 3.59 × 10-24 ; quadratic trend: t = 7.708, p = 2.25 × 10-13 ; adjusted R2 = 0.475), followed by NfL (linear trend: t = 6.542, p = 2.9 × 10-10 ; quadratic trend: t = 3.896, p = 1.22 × 10-4 ; adjusted R2 = 0.330), p-tau181 (linear trend: t = 8.452, p = 1.61 × 10-15 ; quadratic trend: t = 6.316, p = 1.05 × 10-9 ; adjusted R2 = 0.346) and Aß42/Aß40 (linear trend: t = -3.257, p = 1.27 × 10-3 ; quadratic trend: t = -1.662, p = 9.76 × 10-2 ; adjusted R2 = 0.101). Local efficiency decreased in brain regions across the frontal and temporal cortex and striatum. The principal component of local efficiency within these regions was correlated with GFAP (Pearson's R = -0.61, p = 6.3 × 10-7 ), NfL (R = -0.57, p = 6.4 × 10-6 ), and p-tau181 (R = -0.48, p = 2.0 × 10-4 ). Moreover, network efficiency mediated the relationship between general cognition and GFAP (ab = -0.224, 95% confidence interval [CI] = [-0.417 to -0.029], p = .0196 for MMSE; ab = -0.198, 95% CI = [-0.42 to -0.003], p = .0438 for MOCA) or NfL (ab = -0.224, 95% CI = [-0.417 to -0.029], p = .0196 for MMSE; ab = -0.198, 95% CI = [-0.42 to -0.003], p = .0438 for MOCA). Our findings suggest that network efficiency mediates the association between plasma biomarkers, specifically GFAP and NfL, and cognitive performance in the context of AD progression, thus highlighting the potential utility of network-plasma approaches for early detection, monitoring, and intervention strategies in the management of AD.


Assuntos
Doença de Alzheimer , Conectoma , Substância Branca , Humanos , Doença de Alzheimer/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Estudos Retrospectivos , Peptídeos beta-Amiloides , Biomarcadores , Proteínas tau
3.
Artigo em Inglês | MEDLINE | ID: mdl-38976036

RESUMO

PURPOSE: [18F]-D3FSP is a new ß-amyloid (Aß) PET imaging tracer designed to decrease nonspecific signals in the brain by reducing the formation of the N-demethylated product. However, its optimal reference region for calculating the standardized uptake value ratio (SUVR) and its relation to the well-established biomarkers of Alzheimer's disease (AD) are still unclear. METHODS: We recruited 203 participants from the Greater Bay Area Healthy Aging Brain Study (GHABS) to undergo [18F]-D3FSP Aß PET imaging. We analyzed plasma Aß42/Aß40, p-Tau181, glial fibrillary acidic protein (GFAP), and neurofilament light (NfL) using the Simoa platform. We compared the standardized uptake value (SUV) of five reference regions (cerebellum, cerebellum cortex, brainstem/PONs, white matter, composite of the four regions above) and AD typical cortical region (COMPOSITE) SUVR among different clinical groups. The association of D3FSP SUVR with plasma biomarkers, imaging biomarkers, and cognition was also investigated. RESULTS: Brainstem/PONs SUV showed the lowest fluctuation across diagnostic groups, and COMPOSITE D3FSP SUVR had an enormous effect distinguishing cognitively impaired (CI) individuals from cognitively unimpaired (CU) individuals. COMPOSITE SUVR (Referred to brainstem/PONs) was positively correlated with p-Tau181 (p < 0.001), GFAP (p < 0.001), NfL (p = 0.014) in plasma and temporal-metaROI tau deposition (p < 0.001), and negatively related to plasma Aß42/Aß40 (p < 0.001), temporal-metaROI cortical thickness (p < 0.01), residual hippocampal volume (p < 0.001) and cognition (p < 0.001). The voxel-wise analysis replicated these findings. CONCLUSION: This study suggests brainstem/PONs as an optimal reference region for calculating D3FSP SUVR to quantify cortical Aß plaques in the brain. [18F]-D3FSP could distinguish CI from CU and strongly correlates with well-established plasma biomarkers, tau PET, neurodegeneration, and cognitive decline. However, future head-to-head comparisons of [18F]-D3FSP PET images with other validated Aß PET tracers or postmortem results are crucial.

4.
Alzheimers Dement ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38982860

RESUMO

BACKGROUND: Previous studies have found that Alzheimer's disease (AD)-related plasma markers are associated with amyloid beta (Aß) deposition, but the change of this association in different Aß pathological stages remains unclear. METHODS: Data were obtained from the SILCODE. According to the standardized uptake value ratio (SUVR) and Aß stage classification, correlation analysis was performed among plasma biomarkers, and voxel/SUVR values in the regions of interest (ROI) and clinical scale information, respectively. Mediation analysis was used to study the possible pathways. RESULTS: The proportion of cognitively normal (CN) and subjective cognitive decline (SCD) was the highest in stages A0 to 1, while in stages A2 to 4, the proportion of mild cognitive impairment (MCI) and AD increased. Plasma phosphorylated tau (p-tau)181 and glial fibrillary acidic protein (GFAP) levels were significantly lower in stage A0 compared to the later phases. Two pathways demonstrated fully mediated effects: positron emission tomography (PET) SUVR-plasma p-tau181-Mini-Mental State Examination (MMSE) and PET SUVR-plasma GFAP-MMSE. DISCUSSION: This study demonstrated the role of plasma biomarkers in the early stage of AD, especially in SCD, from both the clinical diagnosis and Aß stage dimensions. HIGHLIGHTS: Plasma ptau181 and GFAP level serve as indicators of early Alzheimer's disease and the pathologic Aß staging classification. A possible ceiling effect of GFAP was observed in the mid-to-late stages of the AD course. This study confirms the role of AD plasma markers in promoting Aß deposition at an early stage, particularly in females with subjective cognitive decline(SCD). The overlapping brain regions of plasma p-tau181, GFAP, and neurofilament light for Aß deposition in the brain in early AD were distributed across various regions, including the posterior cingulate gyrus, rectus gyrus, and inferior temporal gyrus.

5.
Angew Chem Int Ed Engl ; : e202411068, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39137126

RESUMO

Electrochemical conversion from nitrate to ammonia is a key step in sustainable ammonia production. However, it suffers from low productive efficiency or high energy consumption due to a lack of desired electrocatalysts. Here we report nickel cobalt phosphide (NiCoP) catalysts for nitrate-to-ammonia electrocatalysis that display a record-high catalytic current density of -702±7 mA cm-2, ammonia production rate of 5415±26 mmol gcat-1 h-1 and Faraday efficiency of 99.7±0.2 % at -0.3 V vs. RHE, affording the estimated energy consumption as low as 22.7 kWh kgammonia-1. Theoretical and experimental results reveal that these catalysts benefit from hydrogen poisoning effects under low overpotentials, which leave behind catalytically inert adsorbed hydrogen species (HI*) at Co-hollow sites and thereupon enable ideally reactive HII* at secondary Co-P sites. The dimerization between HI* and HII* for H2 evolution is blocked due to the catalytic inertia of HI* thereby the HII* drives nitrate hydrogenation timely. With these catalysts, the continuous ammonia production is further shown in an electrolyser with a real energy consumption of 18.9 kWh kgammonia-1.

6.
J Am Chem Soc ; 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37023255

RESUMO

The development of an enantioselective catalytic Suzuki-Miyaura reaction that applies to meso 1,2-diborylcycloalkanes is described. This reaction provides a modular route to enantiomerically enriched substituted carbocycles and heterocycles that retain a synthetically versatile boronic ester. With appropriately constructed substrates, compounds bearing additional stereogenic centers and fully substituted carbon atoms can be generated in a straightforward fashion. Preliminary mechanistic experiments suggest that substrate activation arises from the cooperative effect of vicinal boronic esters during the transmetalation step.

7.
Small ; 19(44): e2303249, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37386788

RESUMO

Oxygen evolution reaction (OER) plays key roles in electrochemical energy conversion devices. Recent advances have demonstrated that OER catalysts through lattice oxygen-mediated mechanism (LOM) can bypass the scaling relation-induced limitations on those catalysts through adsorbate evolution mechanism (AEM). Among various catalysts, IrOx , the most promising OER catalyst, suffers from low activities for its AEM pathway. Here, it is demonstrated that a pre-electrochemical acidic etching treatments on the hybrids of IrOx and Y2 O3 (IrOx /Y2 O3 ) switch the AEM-dominated OER pathway to LOM-dominated one in alkali electrolyte, delivering a high performance with a low overpotential of 223 mV at 10 mA cm-2 and a long-term stability. Mechanism investigations suggest that the pre-electrochemical etching treatments create more oxygen vacancies in catalysts due to the dissolution of yttrium and then provide highly active surface lattice oxygen for participating OER, thereby enabling the LOM-dominated pathway and resulting in a significantly increased OER activity in basic electrolyte.

8.
Crit Rev Food Sci Nutr ; : 1-15, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37800337

RESUMO

Glucose and energy metabolism disorders are the main reasons induced type 2 diabetes (T2D) and obesity. Besides providing energy, dietary nutrients could regulate glucose homeostasis and food intake via intestinal nutrient sensing induced gut hormone secretion. However, reviews regarding intestinal protein sensing are very limited, and no accurate information is available on their underlying mechanisms. Through intestinal protein sensing, dietary proteins regulate glucose homeostasis and food intake by secreting gut hormones, such as glucagon-like peptide 1 (GLP-1), cholecystokinin (CCK), peptide YY (PYY) and glucose-dependent insulinotropic polypeptide (GIP). After activating the sensory receptors, such as calcium-sensing receptor (CaSR), peptide transporter-1 (PepT1), and taste 1 receptors (T1Rs), protein digests induced Ca2+ influx and thus triggered gut hormone release. Additionally, research models used to study intestinal protein sensing have been emphasized, especially several innovative models with excellent physiological relevance, such as co-culture cell models, intestinal organoids, and gut-on-a-chips. Lastly, protein-based dietary strategies that stimulate gut hormone secretion and inhibit gut hormone degradation are proposed for regulating glucose homeostasis and food intake.

9.
Langmuir ; 38(32): 9940-9954, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35917436

RESUMO

The study of the effects of Na and K on the heterogeneous adsorption of hydroxyl-containing char with NO is important for the clean utilization of high alkali coal. In this paper, the effects of Na/K atoms on the adsorption of NO on the char surface were investigated at the GGA-PBE level by choosing zigzag type, armchair type, and saturated hydroxyl-containing char structures based on DFT. It was found that the adsorption stability of NO on structures with active sites was greater for sites close to the hydroxyl group than that for sites far from the hydroxyl group. The stability of char doped by Na/K is related to the char structure and the position of functional groups. The most stable Na/K doped structures are Z-OH-2 (Eads= -350.50 kJ/mol) and A-OH-1-2 (Eads= -339.17 kJ/mol), respectively. The participation of Na/K can increase the adsorption energy of the three structures with NO, and especially the adsorption energy of saturated char with NO is increased by as much as 5 times. The reason for that is the promotion of the hybridization of the C and NO p orbitals. The comprehensive analysis of electrostatic potential, charge transfer, and front orbitals indicates that the effects of decorated sodium and potassium atoms on the char surface are very similar. This study lays a theoretical foundation for the study of the heterogeneous reduction process.

10.
Crit Rev Food Sci Nutr ; : 1-23, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36095057

RESUMO

Dipeptidyl Peptidase IV (DPP-IV) inhibitory peptides are attracting increasing attention, owing to their potential role in glycemic regulation by preventing the inactivation of incretins. However, few reviews have summarized the current understanding of DPP-IV inhibitory peptides and their knowledge gaps. This paper reviews the production, identification and structure-activity relationships (SAR) of DPP-IV inhibitory peptides. Importantly, their bioavailability and hypoglycemic effects are critically discussed. Unlike the traditional method to identifying peptides after separation step by step, the bioinformatics approach identifies peptides via virtual screening that is more convenient and efficient. In addition, the bioinformatics approach was also used to investigate the SAR of peptides. Peptides with proline (Pro) or alanine (Ala) residue at the second position of N-terminal are exhibit strong DPP-IV inhibitory activity. Besides, the bioavailability of DPP-IV inhibitory peptides is related to their gastrointestinal stability and cellular permeability, and in vivo studies showed that the glucose homeostasis has been improved by these peptides. Especially, the intestinal transport of DPP-IV inhibitory peptides and cell biological assays used to evaluate their potential role in glycemic regulation are innovatively summarized. For further successful development of DPP-IV inhibitory peptides in glycemic regulation, future study should elucidate their SAR and in vivo hypoglycemic effects .

11.
J Sci Food Agric ; 102(12): 5495-5501, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35355275

RESUMO

BACKGROUND: The INFOGEST model is a standardized general in vitro digestion study, but it cannot accurately simulate the fatty acid release process of lipids in the stomach and small intestine. In this study, the internationally universal INFOGEST 2019 was used as the basic model and flaxseed oil emulsion was used as the research object. In various improvement models, the effect of fatty acid release rate on the oxidation stability of flaxseed oil was assessed by adding rabbit stomach extract and changing the order of bile salts addition. RESULTS: With the presence of rabbit gastric extract, flaxseed oil emulsion flocculation and coalescence in stomach were reduced, and the absolute value of ζ-potential increased. Moreover, the release rate of fatty acids in the small intestine increased by 12.14%. The amount of lipid oxidation product (i.e. hexanal) in the gastric and intestinal phases increased by 0.08 ppb. In addition, the fatty acid release rate in the small intestine phase increased by 5.85% and the hexanal content increased by 0.011 ppb in the digestion model of adding bile salts before adjusting the pH in the small intestine phase compared with the model of adjusting the pH first and then adding bile salts. CONCLUSION: The results obtained from this study will contribute to finding the most suitable static digestion model for simulating digestion and oxidation of lipid during lipid gastrointestinal digestion. © 2022 Society of Chemical Industry.


Assuntos
Digestão , Óleo de Semente do Linho , Animais , Ácidos e Sais Biliares , Emulsões/química , Ácidos Graxos , Óleo de Semente do Linho/química , Extratos Vegetais , Coelhos
12.
Angew Chem Int Ed Engl ; 61(30): e202205454, 2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35587213

RESUMO

In this paper is described an easily synthesized chiral diazaborolidine that is inexpensive, stable, and provides excellent stereoselection across a number of reaction classes. These versatile compounds possess utility in four different classes of cycloaddition reactions, offering good yield and stereoselectivity. X-ray structure analysis provides insight about the origin of stereocontrol.

13.
Small ; 17(39): e2103018, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34405538

RESUMO

Despite the known efficacy of CeO2 as a promoter in alkaline hydrogen evolution reaction (HER), the underlying mechanism of this effect remains unclear. CoS2 , a pyrite-type alkaline HER electrocatalyst, suffers from sluggish HER kinetics and severe catalyst leaching due to its weak water dissociation kinetics and oxygen-related corrosion. Herein, it is demonstrated that the interfacial Lewis acid-base Ce∙∙∙S pairs in CeO2 -loaded CoS2 effectively improve the catalytic activity and durability. In CeO2 -loaded CoS2 nanowire array electrodes, these interfacial Lewis acid-base Ce∙∙∙S pairs with unique electronic and structural configurations efficiently activate water adsorptive dissociation and kinetically accelerate hydrogen evolution, delivering a low overpotential of 36 mV at 10 mA cm-2 in alkaline media. Such Ce∙∙∙S pairs also weaken O2 adsorption on CoS2 , leading to undecayed activity over 1000 h. These findings are expected to provide guidance for the design of CeO2 -based electrocatalysts as well as other hybrid electrocatalysts for water splitting.

14.
J Gene Med ; 22(11): e3250, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32639657

RESUMO

BACKGROUND: Colorectal cancer (CRC) is a frequently occurring tumor. Although a number of long noncoding RNAs have been researched in CRC, the expression, function and mechanism of AGAP2-AS1 remains poorly investigated. METHODS: Gene expression was analyzed by a quantitative reverse transcriptase-polymerase chain rreaction and western blot analyses. Cell counting kit-8, colony formation and Transwell assays were utilized to explore the functional role of AGAP2-AS1 in CRC. Luciferase reporter, RNA pull down and RNA immunoprecipitation assays were implemented to verify relationships between RNA molecules. RESULTS: In the present study, AGAP2-AS1 was unveiled as highly expressed in CRC cell lines compared to normal cells. AGAP2-AS1 knockdown suppressed cell proliferation, migration, invasion and the epithelial-to-mesenchymal transition process. Interestingly, AGAP2-AS1 sponges miR-4,668-3p to release SRSF1 in CRC. Furthermore, in the rescue functional assay, miR-4,668-3p down-regulation exacerbated the malignant behaviors of AGAP2-AS1-depleted CRC cells, whereas such effects were further offset by SRSF1 knockdown. CONCLUSIONS: AGAP2-AS1 facilitates cell proliferation, motility and EMT in CRC via targeting the miR-4,668-3p/SRSF1 axis. AGAP2-AS1 or SRSF1 may have potential as underlying therapeutic targets for CRC patients.


Assuntos
Movimento Celular , Proliferação de Células , Neoplasias Colorretais/patologia , Transição Epitelial-Mesenquimal , MicroRNAs/genética , RNA Longo não Codificante/genética , Fatores de Processamento de Serina-Arginina/metabolismo , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica , Fatores de Processamento de Serina-Arginina/genética , Células Tumorais Cultivadas
15.
Neuroimmunomodulation ; 27(1): 1-8, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32554968

RESUMO

Several studies have certified that autoantibodies play an important role in the manifestation of neuromuscular diseases. Scientists have discovered specific neuronal tumor antibodies in patients with typical paraneoplastic neurological disorders. But in some clinical cases, it is not useful to cure this disease with common treatments unless the autoantibodies are addressed. In addition, recent studies have shown a close relationship between certain antibodies and neuronal surface proteins in some special cases. These antibodies, which act on the surface of neurons, mainly include voltage-gated calcium channel (VGKC) antibodies. VGKC antibodies are further divided into several types including anti-leucine-rich glioma inactivated 1 (LGI1), anti-contactin-associated protein-like 2 (Caspr2), anti-N-methyl-D-aspartate receptor (NMDAR), anti-α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR), anti-γ-aminobutyric acid receptor (GABAR), and glycine receptor. For the purpose of this review, cases of clinical studies of autoantibody-associated encephalitis were collected, the key points regarding the pathogenesis were summarized, the clinical manifestation was discussed, and all this information was organized as this review in order to introduce the relationship between autoantibodies and autoimmune encephalitis. Furthermore, it is hoped that it can effectively direct the development of diagnostic and therapeutic approach in the future.


Assuntos
Autoanticorpos/imunologia , Encefalite/imunologia , Doença de Hashimoto/imunologia , Humanos , Proteínas de Membrana/imunologia , Neurônios/imunologia
16.
Cell Biol Int ; 42(8): 975-984, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29570903

RESUMO

Gastric cancer (GC) is one of the most common malignancies worldwide. TGF-ß1 induces the epithelial-mesenchymal transition (EMT) in GC, mainly through Smad-dependent pathways. Nevertheless, few studies have focused on the activation of non-canonical transduction pathways. TRPC, Ca2+ entry channels, are ubiquitously expressed in various cell types and are involved in many cellular functions. However, their roles in GC are not well elucidated. This study aimed to determine whether TRPC participates in the TGF-ß1-induced EMT of GC and to investigate the potential mechanisms. Immunofluorescence staining was performed to examine the distribution and expression of TRPCs and EMT-related proteins in SGC-7901 cells incubated with or without TGF-ß1. The expression of TRPC1/3/6 and EMT-related molecules, including E-cadherin, vimentin, and α-SMA, was detected by qRT-PCR and Western blotting. Additionally, the underlying mechanism was determined by treating cells with pharmacological inhibitors and examining the levels of proteins involved in the main signaling cascades using Western blotting. TRPC1/3/6 were expressed at high levels in SGC-7901 cells. Following TGF-ß1 stimulation, the expression of vimentin, α-SMA, and TRPC1/3/6 increased and E-cadherin expression decreased, accompanied by activation of the Ras/Raf1/ERK1/2 signaling pathway. Notably, activation of the Ras/Raf1/ERK1/2 signaling cascade was suppressed by SKF96365 and 2-APB. Both TRPC and ERK inhibitors mitigated EMT progression. Based on these results, TRPC1/3/6 inhibition attenuated the TGF-ß1-induced EMT in GC by suppressing Ras/Raf1/ERK signal transduction.


Assuntos
Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Canais de Cátion TRPC/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Actinas/genética , Actinas/metabolismo , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Imidazóis/farmacologia , Proteínas Proto-Oncogênicas c-raf/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Canais de Cátion TRPC/antagonistas & inibidores , Canal de Cátion TRPC6/antagonistas & inibidores , Canal de Cátion TRPC6/metabolismo , Vimentina/genética , Vimentina/metabolismo , Proteínas ras/metabolismo
17.
Med Sci Monit ; 24: 7137-7145, 2018 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-30293085

RESUMO

BACKGROUND Accumulating studies demonstrate that microRNAs play crucial roles in multiple processes of cancer progression. Lower levels of miR-183 have been observed in diverse types of tumors but the mechanism and precise function of miR-183-5p in cervical cancer have largely not been investigated. MATERIAL AND METHODS The level of miR-183-5p in different cervical cancer cell lines and clinical tissues was detected qRT-PCR assays. Transwell and wound-healing migration assays were conducted to assess the functional roles of miR-183-5p in over-expressing cervical cancer cells in vitro. Rescue assays were carried out to confirm the contribution of integrin subunit Beta 1 (ITGB1) to the aggressiveness of cancer cells regulated by miR-183-5p. RESULTS miR-183-5p was reduced in clinical tissues of cervical cancer and cell lines when compared to the normal subjects and normal cervical epithelial cell line, respectively. In addition, over-expression of miR-183-5p markedly inhibited migration and invasion in cervical cancer cells, and increased aggressiveness was observed in miR-183-5p inhibitor transfected cells. Furthermore, the luciferase reporter assays revealed that ITGB1 was the gene directly regulated by miR-183-5p. Notably, a negative association between the ITGB1 and miR-183-5p was found, and the gene expressions of ITGB1 was mediated by miR-183-5p in cervical cancer cells. CONCLUSIONS miR-183-5p serves as a latent anti-oncogene by targeting the metastasis-promoter gene, ITGB1.


Assuntos
Integrina beta1/metabolismo , MicroRNAs/metabolismo , Neoplasias do Colo do Útero/genética , Regiões 3' não Traduzidas , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Humanos , Integrina beta1/genética , MicroRNAs/genética , Invasividade Neoplásica/genética , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
18.
Cell Physiol Biochem ; 43(2): 481-491, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28934735

RESUMO

BACKGROUND/AIMS: Shikonin, a compound extracted from Zicao, has been demonstrated to hold anti-bacterial, anti-inflammatory, and anti-tumor activities in various diseases and it has been shown to protect human organs from injuries. However, the effect of shikonin on the recovery of spinal cord injury (SCI) remains unknown. This study was designed to estimate the potential therapeutic effect and underlying mechanism of shikonin on SCI in vivo. METHODS: In the study, we used HE staining, ELISA assay, transfection assay, TUNEL assay, real time PCR and Western blot to detect the effects of shikonin on spinal cord injury in rats. RESULTS: we showed that shikonin could promote the recovery of motor function and tissue repair after SCI treatment in rats SCI model. Moreover, we demonstrated that shikonin inhibited the spinal cord edema in SCI model of rats. According to further investigation, shikonin induced the reduction of inflammatory response through decreasing the expression levels of HMGB1, TLR4 and NF-κB after SCI injury. In addition, we also found that shikonin could suppress the apoptosis and expression of caspase-3 protein in SCI model of rats. CONCLUSION: Our results demonstrated that shikonin induced the recovery of tissue repair and motor function via inactivation of HMGB1/TLR4/NF-κB signaling pathway in SCI model of rats. Meanwhile, shikonin regulated the inflammation response in SCI by suppressing the HMGB1/TLR4/NF-κB signaling pathway. The described mechanism sheds novel light on molecular signaling pathway in spinal cord injury and secondary injury including inflammatory response.


Assuntos
Anti-Inflamatórios/uso terapêutico , Proteína HMGB1/imunologia , NF-kappa B/imunologia , Naftoquinonas/uso terapêutico , Traumatismos da Medula Espinal/tratamento farmacológico , Medula Espinal/efeitos dos fármacos , Receptor 4 Toll-Like/imunologia , Animais , Proteína HMGB1/análise , Masculino , NF-kappa B/análise , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Transdução de Sinais/efeitos dos fármacos , Medula Espinal/imunologia , Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/imunologia , Traumatismos da Medula Espinal/fisiopatologia , Receptor 4 Toll-Like/análise
19.
Angew Chem Int Ed Engl ; 56(17): 4777-4781, 2017 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-28338284

RESUMO

The palladium-catalyzed asymmetric synthesis of enone-based atropisomers from 2-iodo-3-methylcyclohex-2-enones and aryl boronic acid is reported. BoPhoz-type phosphine-aminophosphine ligands showed superior enantioselectivity over other ligands. These cyclohexenone-based atropisomers are useful compounds for further elaboration. The divergent synthesis of biaryl atropisomers with different ortho substituents was demonstrated.

20.
PLoS One ; 19(4): e0302104, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38625864

RESUMO

The explosive growth of dialogue data has aroused significant interest among scholars in abstractive dialogue summarization. In this paper, we propose a novel sequence-to-sequence framework called DS-SS (Dialogue Summarization with Factual-Statement Fusion and Dialogue Segmentation) for summarizing dialogues. The novelty of the DS-SS framework mainly lies in two aspects: 1) Factual statements are extracted from the source dialogue and combined with the source dialogue to perform the further dialogue encoding; and 2) A dialogue segmenter is trained and used to separate a dialogue to be encoded into several topic-coherent segments. Thanks to these two aspects, the proposed framework may better encode dialogues, thereby generating summaries exhibiting higher factual consistency and informativeness. Experimental results on two large-scale datasets SAMSum and DialogSum demonstrate the superiority of our framework over strong baselines, as evidenced by both automatic evaluation metrics and human evaluation.

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