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1.
ACS Omega ; 9(25): 27104-27112, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38947830

RESUMEN

The combustion of lithium-ion batteries is characterized by fast ignition, prolonged duration, high combustion temperature, release of significant energy, and generation of a large number of toxic gases. Fine water mist has characteristics such as a high fire extinguishing efficiency and environmental friendliness. In order to thoroughly investigate the temperature control effect of fine water mist on lithium-ion battery fires. This study employs numerical simulation methods, utilizing PyroSim software to simulate the fire process in lithium-ion battery energy storage compartments. First, we focus on the variation patterns of flame, changes in combustion temperature, and heat release rate over time at environmental temperatures of 10, 25, and 35 °C. Subsequently, the suppression of flame, reduction in temperature, and changes in heat release rate are simulated for water mist in lithium-ion battery fires. The simulation results indicate that the environmental temperature has a considerable impact on the flame but a lesser effect on the heat release rate. Fine water mist effectively impedes the spread of thermal runaway between internal battery core cells, leading to a reduction in the flame size and a significant decrease in the maximum temperature and heat release rate. The numerical simulation results can provide scientific guidance for the prevention and control of fires in lithium-ion battery energy storage compartments.

2.
Chem Soc Rev ; 53(12): 6042-6067, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38770558

RESUMEN

A steady stream of material transport based on carriers and channels in living systems plays an extremely important role in normal life activities. Inspired by nature, researchers have extensively applied supramolecular cages in cargo transport because of their unique three-dimensional structures and excellent physicochemical properties. In this review, we will focus on the development of supramolecular cages as carriers and channels for cargo transport in abiotic and biological systems over the past fifteen years. In addition, we will discuss future challenges and potential applications of supramolecular cages in substance transport.

3.
Adv Sci (Weinh) ; 11(21): e2308181, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38459671

RESUMEN

Developing synthetic molecular devices for controlling ion transmembrane transport is a promising research field in supramolecular chemistry. These artificial ion channels provide models to study ion channel diseases and have huge potential for therapeutic applications. Compared with self-assembled ion channels constructed by intermolecular weak interactions between smaller molecules or cyclic compounds, metallacage-based ion channels have well-defined structures and can exist as single components in the phospholipid bilayer. A naphthalene diimide-based artificial chloride ion channel is constructed through efficient subcomponent self-assembly and its selective ion transport activity in large unilamellar vesicles and the planar lipid bilayer membrane by fluorescence and ion-current measurements is investigated. Molecular dynamics simulations and density functional theory calculations show that the metallacage spans the entire phospholipid bilayer as an unimolecular ion transport channel. This channel transports chloride ions across the cell membrane, which disturbs the ion balance of cancer cells and inhibits the growth of cancer cells at low concentrations.

4.
Nat Commun ; 14(1): 7681, 2023 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-37996421

RESUMEN

Electroreduction of CO2 to valuable multicarbon (C2+) products is a highly attractive way to utilize and divert emitted CO2. However, a major fraction of C2+ selectivity is confined to less than 90% by the difficulty of coupling C-C bonds efficiently. Herein, we identify the stable Cu0/Cu2+ interfaces derived from copper phosphate-based (CuPO) electrocatalysts, which can facilitate C2+ production with a low-energy pathway of OC-CHO coupling verified by in situ spectra studies and theoretical calculations. The CuPO precatalyst shows a high Faradaic efficiency (FE) of 69.7% towards C2H4 in an H-cell, and exhibits a significant FEC2+ of 90.9% under industrially relevant current density (j = -350 mA cm-2) in a flow cell configuration. The stable Cu0/Cu2+ interface breaks new ground for the structural design of electrocatalysts and the construction of synergistic active sites to improve the activity and selectivity of valuable C2+ products.

5.
Zhongguo Gu Shang ; 36(11): 1058-64, 2023 Nov 25.
Artículo en Chino | MEDLINE | ID: mdl-38012875

RESUMEN

OBJECTIVE: To evaluate the feasibility of S2 alar iliac screw insertion in Chinese children using computerized three-dimension reconstruction and simulated screw placement technique, and to optimize the measurement of screw parameters. METHODS: A total of 83 pelvic CT data of children who underwent pelvic CT scan December 2018 to December 2020 were retrospectively analyzed, excluding fractures, deformities, and tumors. There were 44 boys and 39 girls, with an average age of (10.66±3.52) years, and were divided into 4 groups based on age (group A:5 to 7 years old;group B:8 to 10 years old;group C:11-13 years old;group D:14 to 16 years old). The original CT data obtained were imported into Mimics software, and the bony structure of the pelvis was reconstructed, and the maximum and minimum cranial angles of the screws were simulated in the three-dimensional view with the placement of 6.5 mm diameter S2 alar iliac screws. Subsequently, the coronal angle, sagittal angle, transverse angle, total length of the screw, length of the screw in the sacrum, width of the iliac, and distance of the entry point from the skin were measured in 3-Matic software at the maximum and minimum head tilt angles, respectively. The differences among the screw parameters of S2 alar iliac screws in children of different ages and the differences between gender and side were compared and analyzed. RESULTS: In all 83 children, 6.5 mm diameter S2 iliac screws could be placed. There was no significant difference between the side of each screw placement parameter. The 5 to 7 years old children had a significantly smaller screw coronal angle than other age groups, but in the screw sagittal angle, the difference was more mixed. The 5 to 7 years old children could obtain a larger angle at the maximum head tilt angle of the screw, but at the minimum cranial angle, the larger angle was obtained in the age group of 11 to 13 years old. There were no significant differences among the age groups. The coronal angle and sagittal angle under maximum cephalic angle and minimum cranial angle of 5 to 7 years old male were (40.91±2.91)° and (51.85±3.75)° respectively, which were significantly greater than in female. The coronal angle under minimum cranial angle was significantly greater in girls aged 8-10 years old than in boys. For the remaining screw placement angle parameters, there were no significant differences between gender. The differences in the minimum iliac width, the screw length, and the length of the sacral screws showed an increasing trend with age in all age groups. The distance from the screw entry point to the skin in boys were significantly smaller than that of girls. The minimum width of the iliac in boys at 14 to 16 years of age were significantly wider than that in girls at the same stage. In contrast, in girls aged 5 to 7 years and 11 to 13 years, the screw length was significantly longer than that of boys at the same stage. CONCLUSION: The pelvis of children aged 5 to 16 years can safely accommodate the placement of 6.5 mm diameter S2 alar iliac screws, but the bony structures of the pelvis are developing and growing in children, precise assessment is needed to plan a reasonable screw trajectory and select the appropriate screw length.


Asunto(s)
Ilion , Fusión Vertebral , Humanos , Masculino , Femenino , Niño , Adolescente , Preescolar , Ilion/cirugía , Estudios Retrospectivos , Estudios de Factibilidad , Tornillos Óseos , Pelvis , Sacro/cirugía , Fusión Vertebral/métodos
6.
J Orthop Surg Res ; 18(1): 466, 2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37380996

RESUMEN

BACKGROUND: There are no studies that have shown the role and underlying mechanism of Polyphyllin I (PPI)-mediated anti-apoptosis activity in nucleus pulposus cells (NPCs). The research aimed to evaluate the effects of PPI in interleukin (IL)-1ß-induced NPCs apoptosis in vitro. METHODS: Cell Counting Kit-8 (CCK-8) assay was used to detect cell viability, and cell apoptosis was evaluated by double-stained flow cytometry (FITC Annexin V/PI). The expression of miR-503-5p was quantified by real-time quantitative PCR (qRT-PCR), and the expression of Bcl-2, Bax, and cleaved caspase-3 was quantified by Western blot. Dual-luciferase reporter gene assay was used to detect the targeting relationship between miR-503-5p and Bcl-2. RESULTS: PPI at 40 µg·mL-1 markedly promoted the viability of NPCs (P < 0.01). Also, PPI inhibited apoptosis and reduction in proliferative activity induced by IL-1ß in the NPCs (P < 0.001, 0.01). PPI treatment significantly inhibited the expression of apoptosis-related protein Bax, cleaved caspase-3 (P < 0.05, 0.01), and enhanced the level of anti-apoptotic protein Bcl-2 (P < 0.01). The proliferative activity of NPCs was significantly decreased and the apoptosis rate of NPCs was increased under IL-1ß treatment (P < 0.01, 0.001). Moreover, miR-503-5p was highly expressed in IL-1ß-induced NPCs (P < 0.001). Furthermore, the effect of PPI on NPCs viability and apoptosis in IL-1ß treatment was dramatically reversed by the overexpression of miR-503-5p (P < 0.01, 0.01). The targeted binding of miR-503-5p to the 3'UTR of Bcl-2 mRNA was confirmed by dual-luciferase reporter gene assays (P < 0.05). In further experiments, compared with miR-503-5p mimics, the effects of PPI on IL-1ß-induced NPCs viability and apoptosis were greatly reversed by the co-overexpression of miR-503-5p and Bcl-2 (P < 0.05, 0.05). CONCLUSION: PPI suppressed the apoptosis of intervertebral disk (IVD) NPCs induced by IL-1ß via miR-503-5p/Bcl-2 molecular axis.


Asunto(s)
MicroARNs , Núcleo Pulposo , Caspasa 3 , Proteína X Asociada a bcl-2 , MicroARNs/genética
7.
Nat Commun ; 14(1): 1599, 2023 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-37072410

RESUMEN

Practical electrochemical CO2-to-CO conversion requires a non-precious catalyst to react at high selectivity and high rate. Atomically dispersed, coordinatively unsaturated metal-nitrogen sites have shown great performance in CO2 electroreduction; however, their controllable and large-scale fabrication still remains a challenge. Herein, we report a general method to fabricate coordinatively unsaturated metal-nitrogen sites doped within carbon nanotubes, among which cobalt single-atom catalysts can mediate efficient CO2-to-CO formation in a membrane flow configuration, achieving a current density of 200 mA cm-2 with CO selectivity of 95.4% and high full-cell energy efficiency of 54.1%, outperforming most of CO2-to-CO conversion electrolyzers. By expanding the cell area to 100 cm2, this catalyst sustains a high-current electrolysis at 10 A with 86.8% CO selectivity and the single-pass conversion can reach 40.4% at a high CO2 flow rate of 150 sccm. This fabrication method can be scaled up with negligible decay in CO2-to-CO activity. In situ spectroscopy and theoretical results reveal the crucial role of coordinatively unsaturated metal-nitrogen sites, which facilitate CO2 adsorption and key *COOH intermediate formation.

8.
Drugs Context ; 122023.
Artículo en Inglés | MEDLINE | ID: mdl-36876155

RESUMEN

Background: Prucalopride is a selective serotonin type 4 (5-HT4) receptor agonist indicated for treatment of chronic idiopathic constipation (CIC) in adults (2 mg orally, daily). 5-HT4 receptors are present in the central nervous system; therefore, non-clinical and clinical assessments were performed to evaluate the tissue distribution and abuse potential of prucalopride. Methods: In vitro receptor-ligand binding studies were performed to assess the affinity of prucalopride (≤1 mM) for peptide receptors, ion channels, monoamine neurotransmitters and 5-HT receptors. The tissue distribution of 14C-prucalopride (5 mg base-equivalent/kg) was investigated in rats. Behavioural assessments in mice, rats and dogs after treatment with single or repeated (up to 24 months) subcutaneous or oral doses of prucalopride (0.02-640 mg/kg across species) were performed. Treatment-emergent adverse events possibly indicative of abuse potential during prucalopride CIC clinical trials were evaluated. Results: Prucalopride showed no appreciable affinity for the receptors and ion channels investigated; its affinity (at ≤100 µM) for other 5-HT receptors was 150-10,000 times lower than that for the 5-HT4 receptor. In rats, <0.1% of the administered dose was found in the brain and concentrations were below the limit of detection within 24 hours. At supratherapeutic doses (≥20 mg/kg), mice and rats exhibited palpebral ptosis, and dogs exhibited salivation, eyelid tremors, decubitis, pedalling movements and sedation. All clinical treatment-emergent adverse events, possibly indicative of abuse potential, except dizziness, occurred in <1% of patients treated with prucalopride or placebo. Conclusion: This series of non-clinical and clinical studies suggest low abuse potential for prucalopride.

9.
Eur J Med Res ; 28(1): 83, 2023 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-36805825

RESUMEN

BACKGROUND: Benign prostatic hyperplasia (BPH) is a common disease in elderly males, and many kinds of minimally invasive procedures can be used for the treatment of BPH. However, various procedures have caused some controversies regarding clinical outcomes, so more studies are needed to validate these controversial topics. AIMS: This study aimed to explore differences of clinical efficacy, surgical features, and complications between transurethral resection of the prostate (TURP) and plasmakinetic enucleation of the prostate (PKEP) for BPH. METHODS: A total of eligible 850 cases of BPH underwent TURP (the TURP group, 320 cases) or PKEP (the PKEP group, 530 cases) in the urology department of our hospital from March 2015 to 2018 were involved in this study. Then, the baseline data, surgical characteristics, IPSS, QoL, PVR, Qmax, IIEF-5, and documented complications were compared between the two groups. RESULTS: The operative time, intraoperative irrigation volume, postoperative hemoglobin, decrease in hemoglobin, postoperative irrigation time and volume, catheterization time, and hospital stay of the PKEP group were significantly less than those of the TURP group (all P < 0.05). At 3 months, 1, 2, and 3 years after operation, no significant differences were observed in IPSS, QoL, PVR, but the results of Qmax and IIEF-5 in the PKEP group were significantly higher than those parameters in the TURP group (all P < 0.05). The incidences of massive blood loss, postoperative secondary bleeding, blood transfusion, capsular perforation, urinary tract irritation, bladder spasm, clot retention, urinary tract infection, transient incontinence, erectile dysfunction, and the incidences of II, III grade of Clavien-Dindo classification in the PKEP group were significantly lower than those of the TURP group (all P < 0.05). CONCLUSION: The clinical efficacy of PKEP is compared favorably with TURP during midterm follow-up. Given the merits such as less blood loss and hospital stay, lower complications, PKEP should be given a priority for BPH.


Asunto(s)
Hiperplasia Prostática , Resección Transuretral de la Próstata , Anciano , Masculino , Humanos , Resección Transuretral de la Próstata/efectos adversos , Próstata/cirugía , Hiperplasia Prostática/cirugía , Calidad de Vida , Resultado del Tratamiento , Hemorragia Posoperatoria
10.
Chemphyschem ; 24(8): e202200657, 2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-36646629

RESUMEN

The discovery of high-performance catalysts for the electrochemical CO2 reduction reaction (CO2 RR) has faced an enormous challenge for years. The lack of cognition about the surface active structures or centers of catalysts in complex conditions limits the development of advanced catalysts for CO2 RR. Recently, the positive valent metal sites (PVMS) are demonstrated as a kind of potential active sites, which can facilitate carbon dioxide (CO2 ) activation and conversation but are always unstable under reduction potentials. Many advanced technologies in theory and experiment have been utilized to understand and develop excellent catalysts with PVMS for CO2 RR. Here, we present an introduction of some typical catalysts with PVMS in CO2 RR and give some understanding of the activity and stability for these related catalysts.

11.
Small Methods ; 6(12): e2201130, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36333185

RESUMEN

Hydrogen generated by proton exchange membrane (PEM) electrolyzer holds a promising potential to complement the traditional energy structure and achieve the global target of carbon neutrality for its efficient, clean, and sustainable nature. The acidic oxygen evolution reaction (OER), owing to its sluggish kinetic process, remains a bottleneck that dominates the efficiency of overall water splitting. Over the past few decades, tremendous efforts have been devoted to exploring OER activity, whereas most show unsatisfying stability to meet the demand for industrial application of PEM electrolyzer. In this review, systematic considerations of the origin and strategies based on OER stability challenges are focused on. Intrinsic deactivation of the material and the extrinsic balance of plant-induced destabilization are summarized. Accordingly, rational strategies for catalyst design including doping and leaching, support effect, coordination effect, strain engineering, phase and facet engineering are discussed for their contribution to the promoted OER stability. Moreover, advanced in situ/operando characterization techniques are put forward to shed light on the OER pathways as well as the structural evolution of the OER catalyst, giving insight into the deactivation mechanisms. Finally, outlooks toward future efforts on the development of long-term and practical electrocatalysts for the PEM electrolyzer are provided.

12.
Adv Mater ; 34(39): e2202568, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35963789

RESUMEN

The electrochemical CO2 reduction reaction (CO2 RR) provides an economically feasible way for converting green energy into valuable chemical feedstocks and fuels. Great progress has been achieved in the understanding and synthesis of oxidized-based precatalysts; however, their dynamical changes of local structure under operando conditions still hinder their further applications. Here a molecularly distorted Bi2 CuO4 precatalyst for efficient CO2 -to-formate conversion is reported. X-ray absorption fine structure (XAFS) results and theoretical calculations suggest that the distorted structure with molecularly like [CuO4 ]6- unit rotation is more conducive to the structural stability of the sample. Operando XAFS and scanning transmission electron microscopy (STEM) results prove that quite a bit of lattice oxygen can remain in the distorted sample after CO2 RR. Electrochemical measurements of the distorted sample show an excellent activity and selectivity with a high formate partial current density of 194.6 mA cm-2 at an extremely low overpotential of -400 mV. Further in situ surface-enhanced infrared absorption spectroscopy (SEIRAS) and density functional theory (DFT) calculations illustrate that the retained oxygen can optimize the adsorption of *OCHO intermediate for the enhanced CO2 RR performance.

13.
Small ; 18(19): e2200303, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35388963

RESUMEN

High-valence metal-doped multimetal (oxy)hydroxides outperform noble metal electrocatalysts for the oxygen evolution reaction (OER) owing to the modified energetics between 3d metals and high-valence dopants. However, the rational design of sufficient and subtle modulators is still challenging. With a multimetal layered double hydroxide (LDH) as the OER catalyst, this study introduces a series of operando high-valence dopants (Cr, Ru, Ce, and V), which can restrict the 3+ valence states in the LDH template to prevent phase separation and operando transfer to the >3+ valence states for sufficient electronic interaction during the OER process. Through density functional theory simulations, ultrathin Cr-doped NiFe (NiFeCr) LDH is synthesized with strong electronic interaction between Cr dopants and NiFe bimetallic sites, evidenced by X-ray absorption spectroscopy. The resulting NiFeCr-LDH catalyzes the OER with ultralow overpotentials of 189 and 284 mV, obtaining current densities of 10 and 1000 mA cm-2 , respectively. Further, a NiFeCr-LDH anode is coupled in the anion exchange membrane electrolyzers to promote alkaline water splitting and CO2 -to-CO electrolysis, which achieves low full cell voltages at high current densities.

14.
J Med Chem ; 63(13): 7226-7242, 2020 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-32456431

RESUMEN

Oral factor XIa (FXIa) inhibitors may provide a promising new antithrombotic therapy with an improved benefit to bleeding risk profile over existing antithrombotic agents. Herein, we report application of a previously disclosed cyclic carbamate P1 linker which provided improved oral bioavailability in the imidazole-based 13-membered macrocycle to the 12-membered macrocycle. This resulted in identification of compound 4 with desired FXIa inhibitory potency and good oral bioavailability but high in vivo clearance. Further structure-activity relationship (SAR) studies of heterocyclic core modifications to replace the imidazole core as well as various linkers to the P1 group led to the discovery of compound 6f, a potent FXIa inhibitor with selectivity against most of the relevant serine proteases. Compound 6f also demonstrated excellent pharmacokinetics (PK) profile (high oral bioavailability and low clearance) in multiple preclinical species. Compound 6f achieved robust antithrombotic efficacy in a rabbit efficacy model at doses which preserved hemostasis.


Asunto(s)
Factor XIa/antagonistas & inhibidores , Fibrinolíticos/administración & dosificación , Fibrinolíticos/farmacología , Administración Oral , Animales , Disponibilidad Biológica , Cristalografía por Rayos X , Perros , Evaluación Preclínica de Medicamentos , Factor XIa/química , Factor XIa/metabolismo , Fibrinolíticos/química , Fibrinolíticos/farmacocinética , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Compuestos Macrocíclicos/administración & dosificación , Compuestos Macrocíclicos/química , Compuestos Macrocíclicos/farmacocinética , Compuestos Macrocíclicos/farmacología , Modelos Moleculares , Conejos , Relación Estructura-Actividad
15.
Eur Spine J ; 29(10): 2484-2490, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32347391

RESUMEN

PURPOSE: This study aims at evaluating the effects of RTS (rotation softened trauma fixation system) compared with PCPSF (percutaneous conventional pedicle screw fixation) on type A thoracolumbar fractures. METHODS: In this retrospective cohort study, 116 patients with type A thoracolumbar fractures from March 2014 to June 2018 were enrolled. PCPSF was performed in 60 patients, meanwhile the other 56 patients accepted RTS. VAS scores, Cobb angle, anterior vertebral height (AVH) and perioperative data were compared between the two groups. RESULTS: Both groups were consistent with baseline on demographic and clinical characteristics. No significant difference was observed in VAS score between-group before and after operation. One year after surgery, the VAS score of RTS group was lower than that of PCPSF group (0.7 ± 0.3 vs. 1.5 ± 0.4). The postoperative AVH (%) in PCPSF was 82.3% (95%CI, 81.7-84.6), and 91.78% (95% CI, 91.1-92.4) in RTS. The postoperative improvement rate of AVH (%) in RTS was higher than that in PCPSF (30.6 ± 5.0 [95% CI, 29.2-32.0] vs. 22.0 ± 7.3 [95% CI, 20.2-24.2]). The postoperative Cobb angle (°) in PCPSF was 2.6 ± 3.4 (95%CI,11.7-13.5), and 7.5 ± 2.0 (95%CI,7.0-8.0) in RTS. The postoperative correction of Cobb angle (°) in RTS was higher than that in PCPSF (16.1 ± 3.8 95%CI,15.1-17.1] vs. 11.6 ± 5.2 95%CI,10.3-13.1]). CONCLUSIONS: Compared with PCPSF, RTS has advantages in restoring the anterior vertebral height and reducing local kyphosis.


Asunto(s)
Tornillos Pediculares , Fracturas de la Columna Vertebral , Fijación Interna de Fracturas , Humanos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/lesiones , Vértebras Lumbares/cirugía , Estudios Retrospectivos , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/cirugía , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/lesiones , Vértebras Torácicas/cirugía , Resultado del Tratamiento
16.
Regul Toxicol Pharmacol ; 112: 104586, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31972188

RESUMEN

Prucalopride, a high affinity, selective serotonin type 4 (5-HT4) receptor agonist, was associated with increased neoplasia incidence (in endocrine tissues and liver) in 2-year rodent bioassays, without evidence of a genotoxic mechanism of action. Proposed mechanisms of action involve prolactin and the constitutive androstane receptor (CAR). Epigenetic mechanisms and their relevance to humans are discussed. Data from in vitro and in vivo rodent studies demonstrated that prucalopride-related stimulation of prolactin secretion (via dopamine receptor D2 antagonism at high doses) is a rodent-specific, non-genotoxic mechanism for inducing hyperplasia and neoplasia in prolactin receptor-expressing endocrine tissues. Additional data demonstrated that CAR-mediated liver enzyme induction underlies the observed hepatocellular adenomas and thyroid follicular adenomas in rodents. A 12-month neonatal mouse carcinogenicity study confirmed the lack of a genotoxic mechanism of action. Furthermore, tumors were observed only at very high exposures (200 and 63 fold higher in mice and rats, respectively, than human exposure after a daily therapeutic dose of 2 mg). The studies indicate that non-genotoxic, rodent-specific, epigenetic mechanisms that are considered clinically irrelevant are responsible for the increased incidence of neoplasias associated with very high exposure to prucalopride in rodents, and that prucalopride does not pose a carcinogenic safety risk to humans.


Asunto(s)
Benzofuranos/efectos adversos , Neoplasias de las Glándulas Endocrinas/inducido químicamente , Neoplasias Hepáticas/inducido químicamente , Receptores de Serotonina 5-HT4/metabolismo , Agonistas del Receptor de Serotonina 5-HT4/efectos adversos , Animales , Benzofuranos/sangre , Benzofuranos/farmacología , Humanos , Medición de Riesgo , Agonistas del Receptor de Serotonina 5-HT4/sangre , Agonistas del Receptor de Serotonina 5-HT4/farmacología
17.
Bioorg Med Chem Lett ; 30(4): 126949, 2020 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-31932224

RESUMEN

The discovery of orally bioavailable FXIa inhibitors has been a challenge. Herein, we describe our efforts to address this challenge by optimization of our imidazole-based macrocyclic series. Our optimization strategy focused on modifications to the P2 prime, macrocyclic amide linker, and the imidazole scaffold. Replacing the amide of the macrocyclic linker with amide isosteres led to the discovery of substituted amine linkers which not only maintained FXIa binding affinity but also improved oral exposure in rats. Combining the optimized macrocyclic amine linker with a pyridine scaffold afforded compounds 23 and 24 that were orally bioavailable, single-digit nanomolar FXIa inhibitors with excellent selectivity against relevant blood coagulation enzymes.


Asunto(s)
Aminas/química , Factor XIa/antagonistas & inhibidores , Compuestos Macrocíclicos/química , Inhibidores de Serina Proteinasa/síntesis química , Administración Oral , Animales , Sitios de Unión , Diseño de Fármacos , Factor XIa/metabolismo , Semivida , Compuestos Macrocíclicos/metabolismo , Compuestos Macrocíclicos/farmacocinética , Simulación de Dinámica Molecular , Estructura Terciaria de Proteína , Piridinas/química , Ratas , Inhibidores de Serina Proteinasa/metabolismo , Inhibidores de Serina Proteinasa/farmacocinética , Relación Estructura-Actividad
18.
J Med Chem ; 63(2): 784-803, 2020 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-31833761

RESUMEN

Factor XIa (FXIa) inhibitors are promising novel anticoagulants, which show excellent efficacy in preclinical thrombosis models with minimal effects on hemostasis. The discovery of potent and selective FXIa inhibitors which are also orally bioavailable has been a challenge. Here, we describe optimization of the imidazole-based macrocyclic series and our initial progress toward meeting this challenge. A two-pronged strategy, which focused on replacement of the imidazole scaffold and the design of new P1 groups, led to the discovery of potent, orally bioavailable pyridine-based macrocyclic FXIa inhibitors. Moreover, pyridine-based macrocycle 19, possessing the phenylimidazole carboxamide P1, exhibited excellent selectivity against relevant blood coagulation enzymes and displayed antithrombotic efficacy in a rabbit thrombosis model.


Asunto(s)
Factor XIa/antagonistas & inhibidores , Fibrinolíticos/síntesis química , Fibrinolíticos/farmacología , Piridinas/síntesis química , Piridinas/farmacología , Animales , Disponibilidad Biológica , Coagulación Sanguínea/efectos de los fármacos , Cristalografía por Rayos X , Diseño de Fármacos , Descubrimiento de Drogas , Fibrinolíticos/farmacocinética , Humanos , Imidazoles/síntesis química , Imidazoles/farmacología , Compuestos Macrocíclicos/síntesis química , Compuestos Macrocíclicos/farmacología , Modelos Moleculares , Tiempo de Tromboplastina Parcial , Conejos , Inhibidores de Serina Proteinasa/síntesis química , Inhibidores de Serina Proteinasa/farmacología , Relación Estructura-Actividad , Trombosis/tratamiento farmacológico
19.
J Orthop Surg (Hong Kong) ; 27(3): 2309499019879540, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31645192

RESUMEN

OBJECTIVE: The purpose of this study was to evaluate the feasibility of posterior occipital condyle screw (OCS) placement analysis of the safe trajectory area for screw insertion. METHODS: Computed tomographic angiography scans of patients (46 males and 27 females) with normal occipitocervical structures were obtained consecutively. Vertebral artery (VA)-occiput distance <4.0 mm was defined as "unfeasible" for OCS fixation, and occipital-atlas angulation was measured to assess the feasibility of screw placement. Next, the placement of 3.5 mm diameter OCS was simulated, the probability of breach of structures surrounding occipital condyles was calculated, and placement parameters were analyzed. RESULTS: OCS placement was feasible in 91.1% (133/146) of occipital condyles, and the feasible probability also presented a significant sex-related difference: The probability was higher for males than for females (95.7% vs. 83.3%, p < 0.05). The incidence of anatomical structures injured under screw placement limitation was 18.8% (VA), 81.2% (hypoglossal canal), 59.4% (occipital-atlas joint), and 40.6% (occiput bone surface). There were no significant differences between the left and right condyles in relation to the measured parameters (p > 0.05). The screw range of motion was significantly smaller in females than in males (p < 0.05). The feasibility of OCS placement and OCS range of motion were significantly greater in the kyphosis group (>5°) than in the other two groups (p < 0.05). CONCLUSION: OCS placement is a feasible technique for occipital-cervical fusion. The male group and occipitocervical region kyphosis group had a wider available space for OCS placement. Tangent angulation may be useful for the accurate and safe placement of an OCS.


Asunto(s)
Tornillos Óseos , Angiografía por Tomografía Computarizada/métodos , Simulación por Computador , Imagenología Tridimensional/métodos , Cifosis/cirugía , Hueso Occipital/cirugía , Fusión Vertebral/métodos , Adulto , Anciano , Femenino , Humanos , Cifosis/diagnóstico , Masculino , Persona de Mediana Edad , Hueso Occipital/diagnóstico por imagen , Adulto Joven
20.
Exp Eye Res ; 189: 107836, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31626797

RESUMEN

TAK-639 is a topical, 9-amino acid, synthetic, C-type natriuretic peptide analog in development for the treatment of primary open-angle glaucoma and ocular hypertension. This study investigated the impact of TAK-639 on intraocular pressure (IOP), the levels of TAK-639 in aqueous humor, and the pharmacokinetic/pharmacodynamic relationship of TAK-639 following topical ocular administration to normotensive female Dutch belted rabbits, beagle dogs, and cynomolgus monkeys. In the IOP studies, rabbits (n = 6/group) and dogs (n = 8/group) received a single topical ocular dose of TAK-639 0.03%, 0.1%, 0.3%, or 0.6% in the right eye and vehicle in the left eye; monkeys (n = 8/group) received TAK-639 0.1%, 0.3%, 0.6%, 0.9%, or 1.2% in the right eye only. IOP was measured pre dose and at various time points from 0.5 to 24 h post dose for rabbits, and 1-48 h post dose for dogs and monkeys. To assess exposure in aqueous humor, another set of animals received a single ocular dose of TAK-639 0.03%, 0.1%, 0.3%, or 0.6% (rabbits, n = 20/group; dogs, n = 14/group) or TAK-639 0.3%, 0.6%, or 1.2% (monkeys, n = 10/group) in both eyes. Aqueous humor and plasma were collected at the same post dose time points at which IOP was measured. Aqueous humor and plasma TAK-639 concentrations were measured by liquid chromatography-mass spectrometry, and pharmacokinetic parameters were estimated with non-compartmental analysis. Topical ocular administration of TAK-639 resulted in a dose-dependent decrease in IOP, with maximum mean decreases in IOP ranging from -8.90% to -34.4% in the rabbit, from -16.5% to -26.4% in the dog, and from -3.43% to -13.5% in the monkey. The duration of the IOP-lowering effect was 12 h in the rabbit and monkey and 48 h in the dog. TAK-639 exposure in aqueous humor (both maximum concentration and area under the curve) was also dose dependent, with maximum concentration ranging from 0.152 to 93.6 ng/mL (0.03% and 0.6% doses, respectively) in rabbits, 0.490-13.8 ng/mL (0.03% and 0.3% doses, respectively) in dogs, and 1.16-18.1 ng/mL (0.3% and 1.2% doses, respectively) in monkeys. The pharmacokinetic/pharmacodynamic profile, when fitted to an inhibitory sigmoidal model, demonstrated that TAK-639 exposure in aqueous humor correlated well with IOP reduction in these species. The TAK-639 exposure in aqueous humor at half maximal IOP reduction (EC50) was lower in monkey and dog than in rabbit (0.2 and 0.4 vs. 2.0 ng/mL, respectively). In plasma, quantifiable concentrations of TAK-639 were low and detectable predominantly at early time points. In conclusion, in rabbit, dog, and monkey, a single topical ocular drop of TAK-639 had a significant IOP-lowering effect that correlated well with increases in TAK-639 levels in aqueous humor and resulted in minimal systemic exposure of TAK-639.


Asunto(s)
Antihipertensivos/farmacocinética , Humor Acuoso/metabolismo , Glaucoma de Ángulo Abierto/tratamiento farmacológico , Presión Intraocular/efectos de los fármacos , Péptido Natriurético Tipo-C/análogos & derivados , Administración Tópica , Animales , Antihipertensivos/administración & dosificación , Cromatografía Liquida , Modelos Animales de Enfermedad , Perros , Relación Dosis-Respuesta a Droga , Femenino , Glaucoma de Ángulo Abierto/metabolismo , Macaca fascicularis , Conejos
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