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1.
Small ; : e2402655, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949408

RESUMO

Solution Gated Graphene Field-Effect Transistors (SGGT) are eagerly anticipated as an amplification platform for fabricating advanced ultra-sensitive sensors, allowing significant modulation of the drain current with minimal gate voltage. However, few studies have focused on light-matter interplay gating control for SGGT. Herein, this challenge is addressed by creating an innovative photoelectrochemical solution-gated graphene field-effect transistor (PEC-SGGT) functionalized with enzyme cascade reactions (ECR) for Organophosphorus (OPs) detection. The ECR system, consisting of acetylcholinesterase (AChE) and CuBTC nanomimetic enzymes, selectively recognizes OPs and forms o-phenylenediamine (oPD) oligomers sediment on the PEC electrode, with layer thickness related to the OPs concentration, demonstrating time-integrated amplification. Under light stimulation, the additional photovoltage generated on the PEC gate electrode is influenced by the oPD oligomers sediment layer, creating a differentiated voltage distribution along the gate path. PEC-SGGT, inherently equipped with built-in amplification circuits, sensitively captures gate voltage changes and delivers output with an impressive thousandfold current gain. The seamless integration of these three amplification modes in this advanced sensor allows a good linear range and highly sensitive detection of OPs, with a detection limit as low as 0.05 pm. This work provides a proof-of-concept for the feasibility of light-assisted functionalized gate-controlled PEC-SGGT for small molecule detection.

2.
World J Urol ; 42(1): 14, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38189837

RESUMO

PURPOSE: Bladder neck contracture (BNC) is a rare but intolerant complication after transurethral surgery of prostate. The present study aims to investigate the incidence and risk factors of BNC in patients diagnosed benign prostate hyperplasia (BPH) and following transurethral resection or enucleation of the prostate (TURP/TUEP). METHODS: This retrospective study included 1008 BPH individuals who underwent transurethral surgery of the prostate between January 2017 and January 2022. Patients' demographics, medical comorbidities, urologic characteristics, perioperative parameters, and the presence of BNC were documented. Univariate and multivariate analyses were conducted to identify the risk factors. RESULTS: A total of 2% (20/1008) BPH patients developed BNC postoperatively and the median occurring time was 5.8 months. Particularly, the incidences of BNC were 4.7% and 1.3% in patients underwent Bipolar-TURP and TUEP respectively. Preoperative urinary tract infection (UTI), elevated PSA, smaller prostate volume (PV), bladder diverticulum (BD), and B-TURP were significantly associated with BNC in the univariate analysis. Further multivariate logistic regression demonstrated preoperative UTI (OR 4.04, 95% CI 2.25 to 17.42, p < 0.001), BD (OR 7.40, 95% CI 1.83 to 31.66, p < 0.001), and B-TURP (OR 3.97, 95% CI 1.55 to 10.18, p = 0.004) as independent risk factors. All BNC patients were treated with transurethral incision of the bladder neck (TUIBN) combined with local multisite injection of betamethasone. During a median follow-up of 35.8 months, 35% (7/20) of BNC patients recurred at a median time of 1.8 months. CONCLUSION: BNC was a low-frequency complication following transurethral surgery of prostate. Preoperative UTI, BD, and B-TURP were likely independent risk factors of BNC. TUIBN combined with local multisite injection of betamethasone may be promising choice for BNC treatment.


Assuntos
Contratura , Hiperplasia Prostática , Masculino , Humanos , Bexiga Urinária , Próstata , Estudos Retrospectivos , Hiperplasia Prostática/cirurgia , Contratura/epidemiologia , Contratura/etiologia , Betametasona
3.
Cell Biol Toxicol ; 40(1): 35, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771546

RESUMO

Neural tube defects (NTDs) represent a prevalent and severe category of congenital anomalies in humans. Cadmium (Cd) is an environmental teratogen known to cause fetal NTDs. However, its underlying mechanisms remain elusive. This study aims to investigate the therapeutic potential of lipophagy in the treatment of NTDs, providing valuable insights for future strategies targeting lipophagy activation as a means to mitigate NTDs.We successfully modeled NTDs by Cd exposure during pregnancy. RNA sequencing was employed to investigate the transcriptomic alterations and functional enrichment of differentially expressed genes in NTD placental tissues. Subsequently, pharmacological/genetic (Atg5-/- placentas) experiments confirmed that inducing placental lipophagy can alleviate Cd induced-NTDs. We found that Cd exposure caused NTDs. Further analyzed transcriptomic data from the placentas with NTDs which revealed significant downregulation of low-density lipoprotein receptor associated protein 1(Lrp1) gene expression responsible for positive regulation of low-density lipoprotein cholesterol (LDL-C) transport. Correspondingly, there was an increase in maternal serum/placenta/amniotic fluid LDL-C content. Subsequently, we have discovered that Cd exposure activated placental lipophagy. Pharmacological/genetic (Atg5-/- placentas) experiments confirmed that inducing placental lipophagy can alleviate Cd induced-NTDs. Furthermore, our findings demonstrate that activation of placental lipophagy effectively counteracts the Cd-induced elevation in LDL-C levels. Lipophagy serves to mitigate Cd-induced NTDs by reducing LDL-C levels within mouse placentas.


Assuntos
Cádmio , LDL-Colesterol , Defeitos do Tubo Neural , Placenta , Feminino , Animais , Gravidez , Placenta/metabolismo , Placenta/efeitos dos fármacos , Defeitos do Tubo Neural/genética , Defeitos do Tubo Neural/induzido quimicamente , Defeitos do Tubo Neural/metabolismo , Camundongos , Cádmio/toxicidade , LDL-Colesterol/sangue , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout
4.
Inorg Chem ; 62(49): 20513-20519, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38008909

RESUMO

With the development of crystalline porous materials toward methane storage, the stability issue of metal-organic framework (MOF) materials has caused great concern despite high working capacity. Considering the high stability of zirconium-based MOFs and effective functions of amide groups toward gas adsorption, herein, a series of UiO-66 type of Zr-MOFs, namely, Zr-fcu-H/F/CH3/OH, were successfully designed and synthesized by virtue of amide-functionalized dicarboxylate ligands bearing distinct side groups (i.e., -H, -F, -CH3, and -OH) and ZrCl4 in the presence of trifluoroacetic acid as the modulator. Single-crystal X-ray diffraction and topology analyses reveal that these compounds are archetypal fcu MOFs encompassing octahedral and tetrahedral cages, respectively. The N2 sorption isotherms and acid-base stability tests demonstrate that the materials possess not only relatively high surface areas, pore volumes, and appropriate pore sizes but also great hydrolytic stabilities ranging pH = 3-11. Furthermore, the volumetric methane storage working capacities of Zr-fcu-H, Zr-fcu-F, Zr-fcu-CH3, and Zr-fcu-OH at 298/273 K and 80 bar are 187/217, 175/193, 167/187, and 154/171 cm3 (STP) cm-3, respectively, which indicate that the zirconium-based crystalline porous materials are capable of storing relatively high amounts of methane.

5.
J Asian Nat Prod Res ; 25(11): 1044-1050, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37042722

RESUMO

Two new alkaloids, spongimides A (1) and B (2), along with five known ones (3-7), were isolated from the marine sponge Spongia sp. The structures of 1 and 2 were determined by the spectroscopic methods (UV, IR, MS, and NMR) and X-ray diffraction analysis. Compounds 1, 3, and 4 were the first examples of 2,4-imidazolidinediones isolated from this genus. In addition, the cytotoxic and antibacterial activities of compounds 1 and 2 were also evaluated.


Assuntos
Alcaloides , Antineoplásicos , Poríferos , Animais , Estrutura Molecular , Poríferos/química , Antineoplásicos/química , Alcaloides/química , Espectroscopia de Ressonância Magnética
6.
Angew Chem Int Ed Engl ; 62(27): e202302983, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37154671

RESUMO

Transition-metal catalyzed enantioconvergent cross-coupling of tertiary alkyl halides with ammonia offers a rapid avenue to chiral unnatural α,α-disubstituted amino acids. However, the construction of chiral C-N bonds between tertiary-carbon electrophiles and nitrogen nucleophiles presented a great challenge owing to steric congestion. We report a copper-catalyzed enantioconvergent radical C-N cross-coupling of alkyl halides with sulfoximines (as ammonia surrogates) under mild conditions by employing a chiral anionic N,N,N-ligand with a long spreading side arm. An array of α,α-disubstituted amino acid derivatives were obtained with good efficiency and enantioselectivity. The synthetic utility of the strategy has been showcased by the elaboration of the coupling products into different chiral α-fully substituted amine building blocks.

7.
J Am Chem Soc ; 144(39): 18081-18089, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-36153984

RESUMO

The copper-catalyzed enantioselective intermolecular radical 1,2-carboamination of alkenes with readily accessible alkyl halides is an appealing strategy for producing chiral amine scaffolds. The challenge arises from the easily occurring atom transfer radical addition between alkyl halides and alkenes and the issue of enantiocontrol. We herein describe a radical alkene 1,2-carboamination with sulfoximines in a highly chemo- and enantioselective manner. The key to the success of this process is the conceptual design of a counterion/highly sterically demanded ligand coeffect to promote the ligand exchange of copper(I) with sulfoximines and forge chiral C-N bonds between alkyl radicals and the chiral copper(II) complex. The reaction covers alkenes bearing distinct electronic properties, such as aryl-, heteroaryl-, carbonyl-, and aminocarbonyl-substituted ones, and various radical precursors, including alkyl chlorides, bromides, iodides, and the CF3 source. Facile transformations deliver many chiral amine building blocks of interest in organic synthesis and related areas.


Assuntos
Alcenos , Cobre , Alcenos/química , Aminas , Brometos , Catálise , Cloretos , Cobre/química , Iodetos/química , Ligantes , Estrutura Molecular , Estereoisomerismo
8.
Acta Pharmacol Sin ; 43(7): 1865-1874, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34789919

RESUMO

Furmonertinib (AST2818) is a novel third-generation irreversible EGFR TKI and recently has been approved in China for the treatment of non-small cell lung cancer (NSCLC) with EGFR-sensitizing and T790M resistance mutations. In the current study, we developed a semi-mechanistic population pharmacokinetic model to characterize the nonstationary pharmacokinetics (PK) of the furmonertinib and its active metabolite AST5902 simultaneously. The PK data of furmonertinib and AST5902 were obtained from 38 NSCLC patients and 16 healthy volunteers receiving 20-240 mg furmonertinib in three clinical trials. A nonlinear mixed-effects modeling approach was used to describe the PK data. The absorption process of furmonertinib was described by a transit compartment model. The disposition of both furmonertinib and AST5902 was described by a two-compartment model. An indirect response model accounted for the autoinduction of furmonertinib metabolism mediated by CYP3A4. The model-based simulation suggested that furmonertinib clearance was increased in one cycle of treatment (orally once daily for 21 days) compared to baseline, ranging from 1.1 to 1.8 fold corresponding to the dose range of 20-240 mg. The concentration of furmonertinib was decreased over time whereas that of AST5902 was increased. Interestingly, the concentration of the total active compounds (furmonertinib and AST5902) appeared to be stable. The food intake, serum alkaline phosphatase and body weight were identified as statistically significant covariates. The mechanism of food effect on PK was investigated, where the food intake might increase the bioavailability of furmonertinib via increasing the splanchnic blood flow. Overall, a population PK model was successfully developed to characterize the nonstationary PK of furmonertinib and AST5902 simultaneously. The concentrations of total active compounds were less affected by the autoinduction of furmonertinib metabolism.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Receptores ErbB , Alimentos , Humanos , Modelos Biológicos , Mutação , Inibidores de Proteínas Quinases
9.
J Am Chem Soc ; 143(31): 12202-12211, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34328001

RESUMO

Reticular chemistry and methane storage materials have been predominately focused on finite metal-cluster-based metal-organic frameworks (MOFs). In contrast, MOFs constructed from infinite rod secondary building units (SBUs), i.e., rod MOFs, are less developed, and the existing ones are typically built from simple one-way helical, zigzag, or (mixed)polyhedron SBUs. Herein, inspired by a recent unveiled structure of Zn6(H2O)3(BTP)4 and by means of an amide-functionalized preliminary single tricarboxylate, a subsequent mixed tricarboxylate, and dicarboxylate linkers, an intricate three-way rod MOF and the next three isoreticular three-way rod MOFs have been successfully realized, namely, 3W-ROD-1 and 3W-ROD-2-X (X = -OH, -F, and -CH3), respectively. The structural analyses disclosed that the four compounds were constructed from unprecedented three-way invariant nonintersecting trigonal rod-packing SBUs cross-linked via the noncovalent-interaction-driven self-assembly of pseudo hexacarboxylates with the original tricarboxylate or different functional ditopic linkers, resulting in cage-like pore geometries accessible via ultramicroporous apertures concomitant with the complex topology transitivity, namely, 18 42 and 18 44. Sorption studies show that the apparent surface areas of these materials are among the most highly porous materials for rod MOFs. Due to the presence of favorable pocket sites created by X, ketone, and proximal amide groups as revealed by Monte Carlo molecular dynamics (MCMD) computational calculations, the MOFs exhibit impressive methane storage working capacities, outperforming the well-known rod Ni-MOF-74 and representing the highest values among rigid rod MOFs.

10.
J Am Chem Soc ; 143(37): 15413-15419, 2021 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-34505516

RESUMO

α-Chiral alkyl primary amines are virtually universal synthetic precursors for all other α-chiral N-containing compounds ubiquitous in biological, pharmaceutical, and material sciences. The enantioselective amination of common alkyl halides with ammonia is appealing for potential rapid access to α-chiral primary amines, but has hitherto remained rare due to the multifaceted difficulties in using ammonia and the underdeveloped C(sp3)-N coupling. Here we demonstrate sulfoximines as excellent ammonia surrogates for enantioconvergent radical C-N coupling with diverse racemic secondary alkyl halides (>60 examples) by copper catalysis under mild thermal conditions. The reaction efficiently provides highly enantioenriched N-alkyl sulfoximines (up to 99% yield and >99% ee) featuring secondary benzyl, propargyl, α-carbonyl alkyl, and α-cyano alkyl stereocenters. In addition, we have converted the masked α-chiral primary amines thus obtained to various synthetic building blocks, ligands, and drugs possessing α-chiral N-functionalities, such as carbamate, carboxylamide, secondary and tertiary amine, and oxazoline, with commonly seen α-substitution patterns. These results shine light on the potential of enantioconvergent radical cross-coupling as a general chiral carbon-heteroatom formation strategy.

11.
Ecotoxicol Environ Saf ; 224: 112632, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34411824

RESUMO

Gestational exposure to environmental Cd caused placental angiogenesis impairment and fetal growth restriction (FGR). However, its mechanism remained unclear. This study was to investigate the effects of Cd exposure during pregnancy on placental angiogenesis and its mechanism. Pregnant mice were exposed to CdCl2 (4.5 mg/kg) on gestational day (GD) 8 with or without melatonin (MT) (5.0 mg/kg), an anti-endoplasmic reticulum stress agent, from GD7 to GD15. Human primary placental trophoblasts and JEG-3 cells were stimulated using CdCl2 (20 µM) after MT (1 mM) preprocessing. We firstly found MT treatment obviously mitigated environmental Cd-induced placental angiogenesis disorder and reduction of the VEGF-A level. Mechanistically, MT reversed environmental Cd-downregulated the protein expression of VEGF-A via inhibiting glucocorticoid receptor (GR) activation. Notably, our data showed MT treatment antagonized Cd-activated GC/GR signaling via blocking PERK signaling and thereby upregulated VEGF-A and 11ß-HSD2 protein expression. Based upon the population case-control study, the levels of VEGF-A and 11ß-HSD2 protein in small-for-gestational-age placentae were significantly reduced when compared to appropriate-for-gestational-age placentae. Overall, environmental Cd exposure during gestation impaired placental angiogenesis via PERK-regulated GC/GR signaling in placental trophoblasts. Our findings will provide a basis for prevention and treatment of placental impairments and fetal growth restriction caused by environment toxicants in future.

12.
J Am Chem Soc ; 142(20): 9501-9509, 2020 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32338510

RESUMO

A copper-catalyzed intermolecular three-component asymmetric radical 1,2-carboalkynylation of alkenes has been developed, providing straightforward access to diverse chiral alkynes from readily available alkyl halides and terminal alkynes. The utilization of a cinchona alkaloid-derived multidentate N,N,P-ligand is crucial for the efficient radical generation from mildly oxidative precursors by copper and the effective inhibition of the undesired Glaser coupling side reaction. The substrate scope is broad, covering (hetero)aryl-, alkynyl-, and aminocarbonyl-substituted alkenes, (hetero)aryl and alkyl as well as silyl alkynes, and tertiary to primary alkyl radical precursors with excellent functional group compatibility. Facile transformations of the obtained chiral alkynes have also been demonstrated, highlighting the excellent complementarity of this protocol to direct 1,2-dicarbofunctionalization reactions with C(sp2/sp3)-based reagents.

13.
Inorg Chem ; 59(16): 11233-11237, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32799513

RESUMO

CeIV6-based metal-organic frameworks (MOFs) have gained increasing attention recently because of their diverse potential applications and similarity to prominent Zr-MOFs, e.g., the UiO-66 series. However, the reported CeIV6-based MOFs were all structurally determined by means of the powder X-ray diffraction technique, indicative of less practice and convenience. Herein, four single-crystalline CeIV6-based MOFs were successfully isolated and characterized by single-crystal X-ray diffraction, disclosing two series of topologically distinct isoreticular nets accompanied by nine-coordinated central CeIV ions, i.e., 8-connected hex and 12-connected fcu, respectively, in contrast to the previously reported sole fcu topology based on the combination of linear dicarboxylate ligands and a CeIV6 cluster associated with eight-coordinated central CeIV ions according to the UiO-66 structural model. Moreover, all four single-crystalline compounds exhibit permanent microporous porosities and a certain amount of gas uptake toward CO2, CH4, and H2.

14.
Arch Virol ; 165(9): 1979-1985, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32556549

RESUMO

To evaluate the epigenetic regulation of the VDR gene in enterovirus 71 (EV71)-associated severe hand, foot, and mouth disease (HFMD), a total of 116 patients with EV71-HFMD, including 58 with mild EV71-HFMD and 58 with severe EV71-HFMD, as well as 60 healthy controls, were enrolled in this study. Quantitative real-time PCR was used to measure the relative levels of VDR mRNA expression, and the methylation status of the VDR promoter was assessed using a MethylTarget™ assay. The DNA methylation levels of the VDR promoter in children with EV71-associated severe HFMD were lower than those in the healthy controls and in children with mild HFMD (P < 0.05). Hypomethylation at CpG site 133 and hypermethylation at the CpG 42 sites and 68 downregulated VDR expression. Moreover, the methylation level of VDR could be used for differential diagnosis of mild and severe EV71-associated HFMD (AUC56, 0.73; AUC68, 0.699; AUC42, 0.694; AUC66, 0.693). VDR expression and promoter methylation were associated with the progression of EV71 infection. Determining the VDR promoter status might help clinicians initiate the appropriate strategy for treatment of EV71-associated HFMD.


Assuntos
Enterovirus Humano A/fisiologia , Doença de Mão, Pé e Boca/genética , Receptores de Calcitriol/genética , Criança , Pré-Escolar , China , Enterovirus Humano A/genética , Epigênese Genética , Feminino , Doença de Mão, Pé e Boca/metabolismo , Doença de Mão, Pé e Boca/virologia , Humanos , Lactente , Masculino , Metilação , Regiões Promotoras Genéticas , Receptores de Calcitriol/metabolismo
15.
Angew Chem Int Ed Engl ; 59(13): 5242-5247, 2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-31953978

RESUMO

A strategically novel synthetic method for the fluoroarylation of allenic ester was developed that enables the expedient construction of a host of ß-fluoroalkyl-containing cinnamate derivatives. The reaction proceeds through visible-light-promoted gold redox catalysis, occurs smoothly under very mild reaction conditions, accommodates a large variety of functional groups, and more importantly allows the incorporation of fluorine and aryl groups with excellent regio- and stereoselectivity. The concomitant activation mode for both the allene motif and the hydrogen fluoride is key for the success of the reaction.

16.
Cell Physiol Biochem ; 47(2): 851-863, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29807358

RESUMO

BACKGROUND/AIMS: This study aimed to evaluate whether galectin-3 (Gal-3) contributes actively to atrial fibrosis both in patients and experimental atrial fibrillation (AF) models. METHODS: Mouse HL-1 cardiomyocytes were subjected to rapid electrical stimulation (RES) to explore Gal-3 expression and secretion levels by western blotting (WB) and enzyme linked immunosorbent assay (ELISA). Neonatal rat cardiac fibroblasts were treated with conditioned culture medium and recombinant human Gal-3 to evaluate the activation of the transforming growth factor (TGF)-ß1/α-smooth muscle actin (SMA)/collagen I (Col I) profibrotic pathway (WB) and fibroblast proliferation with a Cell Counting Kit-8 (CCK-8). Furthermore, in the rapid atrial pacing (RAP) rabbit AF model, atrial Gal-3 expression and its effects on the profibrotic pathway were evaluated (WB and Masson's trichrome staining). Moreover, 44 consecutive patients who underwent single mitral valve repair/replacement were included, consisting of 28 patients with persistent AF (PeAF) and 16 with sinus rhythm (SR). Coronary sinus blood was also sampled to test circulating Gal-3 levels (ELISA), and atrial myocardium Gal-3 and its downstream TGF-ß1/α-SMA pathway were also measured by WB and immunohistochemical staining. RESULTS: Gal-3 expression in HL-1 cells and its secretion level in culture medium were greatly increased after 24 h RES. Treatment of neonatal rat cardiac fibroblasts with conditioned media collected from the RES group or recombinant human Gal-3 protein (10 and 30 µg/mL) for 72 h induced the activation of the TGF-ß1/α-SMA/Col I profibrotic pathway. RAP increased Gal-3 levels and activated the TGF-ß1/α-SMA/Col I pathway in rabbit left atria, while the Gal-3 inhibitor N-acetyllactosamine, injected at 4.5 mg/kg every 3 days, mitigated these adverse changes. Furthermore, Gal-3 levels in coronary sinus blood samples and myocardial Gal-3 expression levels were higher in the PeAF patients than in the SR patients, and higher level profibrotic pathway activation was also confirmed. CONCLUSIONS: Activation of Gal-3 expression in the atria can subsequently activate the TGF-ß1/α-SMA/Col I pathway in cardiac fibroblasts, which may enhance atrial fibrosis.


Assuntos
Actinas/metabolismo , Fibrilação Atrial/patologia , Colágeno Tipo I/metabolismo , Galectina 3/farmacologia , Fator de Crescimento Transformador beta1/metabolismo , Idoso , Animais , Fibrilação Atrial/metabolismo , Fibrilação Atrial/veterinária , Estimulação Elétrica , Feminino , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Galectina 3/sangue , Galectina 3/genética , Galectina 3/metabolismo , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Miocárdio/metabolismo , Miocárdio/patologia , Coelhos , Ratos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Respiração Artificial , Transdução de Sinais/efeitos dos fármacos
17.
J Phys Chem A ; 122(39): 7842-7851, 2018 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-30188712

RESUMO

The mechanism of histidine-catalyzed asymmetrical aldol reaction of acetone with benzaldehyde was studied by using B3LYP method of density functional theory at the levels of 6-31G(d,p) and cc-pvdz basis sets. The calculation results showed that the reaction mechanism included four steps: (I) nucleophilic attack of histidine on acetone to form alcohol intermediate Inter-A through the transition state TS1 (considered a rate control step because the activation energy (49.95 kcal/mol) was relatively high); (II) dehydration of the alcohol intermediate to form the cis- or trans-enamine through the transition states TS3 and TS4 with the energy barriers of 36.12 and 38.15 kcal/mol; (III) electrophilic addition of cis-enamine or trans-enamine with benzaldehyde to form imine Inter-C or Inter-E through the transition states TS8, TS9, TS10, and TS11 (energy barriers 18.43, 22.34, 13.24, and 13.24 kcal/mol, respectively); (IV) after combination of the imine intermediate with water through the transition states TS12, TS13, TS14, and TS15 (energy barriers 22.79, 34.6, 28.2, 25.12 kcal/mol, respectively), removal of the histidine catalys to obtain the final S or R aldol product. Through analyzing the potential energy profile of reaction, we found that the histidine-catalyzed reaction of acetone with benzaldehyde was more energetically favorable to obtain the R-product (ee value >99%). Solvent effects computed with a polarizable continuum model (PCM) indicated that the DMSO and water can reduce the reaction energy barrier.

18.
Plant Cell Rep ; 37(11): 1547-1555, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30056500

RESUMO

KEY MESSAGE: The T.118 and T.406 seedlings showed strong adaptability under Cd concentrations ≤ 50 µM. The mechanisms of photoprotection in T.118 and T.406 differed in high-Cd concentrations. To explore the physiological response characteristics of Taxodium hybrids to cadmium (Cd) stress and provide basis for screening of Cd-tolerant species, the hydroponic cultivation of T.118 and T.406 seedlings was conducted to demonstrate the effects of Cd stress on seedling growth, antioxidant system, and chlorophyll fluorescence parameters. After 35 days of Cd stress at a concentration ≤ 50 µM, the dry weight biomass of the two clones did not significantly differ from that of the control. T.406 exhibited a significant increase in POD activity compared to T.118 and maintained high SOD activity after exposure to high concentrations of Cd, whereas MDA levels showed little changes. Under low-Cd stress, chlorophyll content and fluorescence parameters remained stable, especially for T.406. Under high-Cd concentration stress, the above parameters were lower than the control, with a more significant decrease in T.118 than in T.406. The non-photochemical quenching coefficient (NPQ) of both clones increased with increasing Cd concentration. T.118 showed a greater increase than T.406, particularly under high-Cd concentration stress. The T.118 and T.406 seedlings adapted to low-Cd concentration stress by enhancing their antioxidant enzyme activity to maintain the balance of reactive oxygen metabolism and reduce cellular damage. The photochemical activity of mesophyll cells remained high to maintain photosynthetic capacity and normal seedling growth. T.406 showed stronger resistance to Cd than T.118. T.406 prevented photodamage by promoting the photochemical utilization of the excitation energy and maintaining a strong antioxidant stress ability. Enhancement of heat dissipation capability may be the main photoprotection mechanism of T.118.


Assuntos
Antioxidantes/metabolismo , Cádmio/toxicidade , Fotossíntese/efeitos dos fármacos , Taxodium/efeitos dos fármacos , Biomassa , Clorofila/metabolismo , Fluorescência , Hidroponia , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Estresse Fisiológico , Taxodium/crescimento & desenvolvimento , Taxodium/fisiologia
19.
Tumour Biol ; 37(3): 4127-34, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26490983

RESUMO

Accumulating evidence has indicated that long non-coding RNA PVT1 is upregulated in various human cancers. However, it remains unclear whether PVT1 is involved in the development and progression of non-small cell lung cancer (NSCLC). The present study was designed to investigate the expression, biological role, and clinical significance of PVT1 in NSCLC. Our results indicated that PVT1 expression was significantly increased in NSCLC tissues and cell lines, and its upregulation was associated with advanced T-stage and tumor-node-metastasis (TNM) stage and regional lymph node metastasis. PVT1 expression levels were robust in differentiating NSCLC tissues from controls. Kaplan-Meier curve and Cox regression analysis showed that high expression of PVT1 was associated with poor overall survival and disease-free survival in NSCLC patients. The results of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and colony formation assays indicated that knockdown of PVT1 remarkably inhibited NSCLC cell proliferation, whereas overexpression of PVT1 significantly promoted cellular proliferation. In addition, PVT1 knockdown increased the number of cells in the G0/G1 phase and reduced the number of cells in the S phase, while overexpression of PVT1 could promote cell cycle progression. Furthermore, our findings also revealed that the messenger RNA (mRNA) and protein expression of P15 and P21 was significantly upregulated in NSCLC cells transfected with PVT1 small interfering RNA (siRNA) and downregulated in cells transfected with pcDNA3.1-PVT1. In conclusion, our study demonstrated that PVT1 might serve as a promising biomarker for diagnosis and prognosis of NSCLC, and it could promote the proliferation of NSCLC cells by downregulating p15 and p21 expression.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , RNA Longo não Codificante/metabolismo , Área Sob a Curva , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Linhagem Celular Tumoral , Proliferação de Células , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Modelos de Riscos Proporcionais , RNA Longo não Codificante/genética , Curva ROC
20.
BMC Infect Dis ; 16(1): 585, 2016 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-27760526

RESUMO

BACKGROUND: Severe hand, foot, and mouth disease (HFMD) is sometimes associated with serious complications such as acute heart failure that can cause substantial child mortality. N-terminal pro-brain natriuretic peptide (NT-proBNP) is a sensitive and specific biomarker of congestive heart failure. The aim of this study was to use plasma NT-proBNP levels to establish the severity of childhood HFMD. METHODS: A retrospective study was performed in 128 Chinese patients with severe HFMD and 88 patients with mild HFMD treated between January 2014 and October 2015. Univariate and multiple logistic regression analyses were used to analyze the risk factors for severe HFMD. NT-proBNP levels were analyzed in 128 severe HFMD patients, and the predictive value of NT-proBNP was assessed by receiver operating characteristic analyses. RESULTS: Multivariate analysis controlling for several potential confounders showed that enterovirus 71 infection [odds ratio (OR) 19.944, 95 % confidence interval (CI) 6.492-61.271], peripheral WBC count (OR 3.428, 95 % CI 1.186-9.914), fasting glucose (OR 19.428, 95 % CI 2.236-168.784), procalcitonin (OR 9.084, 95 % CI 3.462-23.837, and NT-proBNP (>125 pg/mL) (OR 16.649, 95 % CI 4.731-58.585) were each associated with the severity of HFMD. The 45 dead severe patients had higher pre-procedural levels of NT-proBNP than the 83 cured severe patients (12776 ± 13115 versus 1435 ± 4201 pg/mL, P < 0.001). An NT-proBNP cutoff value of 982 pg/mL predicted mortality with 87 % sensitivity and 86 % specificity. CONCLUSION: Plasma NT-pro-BNP level appears to be a useful biological marker for predicting the severity and mortality of HFMD.


Assuntos
Biomarcadores/sangue , Doença de Mão, Pé e Boca/sangue , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Doença de Mão, Pé e Boca/etiologia , Doença de Mão, Pé e Boca/mortalidade , Humanos , Masculino , Análise Multivariada , Razão de Chances , Curva ROC , Estudos Retrospectivos , Fatores de Risco , Sensibilidade e Especificidade
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