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1.
Cereb Cortex ; 34(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38186007

RESUMO

This study aimed to investigate the relationship between exercise addiction and brain structure in middle-older individuals, and to examine the role of self-efficacy in mediating physiological changes associated with exercise addiction. A total of 133 patients exhibiting symptoms of exercise addiction were recruited for this study (male = 43, age 52.86 ± 11.78 years). Structural magnetic resonance imaging and behavioral assessments were administered to assess the study population. Voxel-based morphological analysis was conducted using SPM12 software. Mediation analysis was employed to explore the potential neuropsychological mechanism of self-efficacy in relation to exercise addiction. The findings revealed a positive correlation between exercise addiction and gray matter volume in the right inferior temporal region and the right hippocampus. Conversely, there was a negative correlation with gray matter volume in the left Rolandic operculum. Self-efficacy was found to indirectly influence exercise addiction by affecting right inferior temporal region gray matter volume and acted as a mediating variable in the relationship between the gray matter volume of right inferior temporal region and exercise addiction. In summary, this study elucidates the link between exercise addiction and brain structure among middle-older individuals. It uncovers the intricate interplay among exercise addiction, brain structure, and psychological factors. These findings enhance our comprehension of exercise addiction and offer valuable insights for the development of interventions and treatments.


Assuntos
Encéfalo , Autoeficácia , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Lobo Parietal , Software , Imageamento por Ressonância Magnética
2.
J Am Chem Soc ; 146(38): 26121-26130, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39099165

RESUMO

The Wacker and Wacker-type reactions are some of the most fundamental and powerful transformations in organic chemistry for their ability to efficiently produce valuable chemicals. Remarkable progress has been achieved in asymmetric oxy/aza-Wacker-type reactions; however, asymmetric Wacker-type dicarbofunctionalization remains underdeveloped, especially for the concurrent construction of two stereocenters. Herein, we report a Pd/Cu-cocatalyzed enantio- and diastereodivergent Wacker-type dicarbofunctionalization of alkene-tethered aryl triflates with imino esters. A series of 2-indanyl motifs bearing adjacent carbon stereocenters could be easily synthesized in moderate to excellent yields and with good to excellent diastereo- and enantioselectivities (up to >20:1 dr and >99% ee). Density functional theory calculations revealed that the origin of diastereoselectivity in this Pd/Cu synergistic catalytic system is jointly determined by both the intermolecular anti-carbopalladation of alkenes and the reductive elimination processes, in accordance with the Curtin-Hammett principle.

3.
Org Biomol Chem ; 22(9): 1850-1858, 2024 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-38345427

RESUMO

ß-Galactosidase (ß-gal), which is responsible for the hydrolysis of the glycosidic bond of lactose to galactose, has been recognized as an important biomarker of cell or organism status, especially cell senescence and primary ovarian cancer. Extensive efforts have been devoted to develop probes for detecting and visualizing ß-gal in cells. Herein, a fluorescent probe gal-HCA which possesses both excited-state intramolecular proton transfer (ESIPT) and aggregation-induced emission (AIE) properties was prepared to monitor ß-gal in living cells. The probe consists of 2-hydroxy-4'-dimethylamino-chalcone (HCA) capped with a D-galactose group. The cleavage of the glycosidic bond in gal-HCA triggered by ß-gal releases HCA, which results in a significant bathochromic shift in fluorescence from 532 to 615 nm. The probe exhibited high selectivity and sensitivity toward ß-gal with a detection limit as low as 0.0122 U mL-1. The confocal imaging investigation demonstrated the potential of gal-HCA in monitoring the endocellular overexpressed ß-gal in senescent cells and ovarian cancer cells. This study provides a straightforward approach for the development of fluorescent probes to monitor ß-gal and detection of ß-gal-associated diseases.


Assuntos
Chalconas , Neoplasias Ovarianas , Feminino , Humanos , Corantes Fluorescentes/química , Prótons , Neoplasias Ovarianas/diagnóstico por imagem , Imagem Óptica/métodos , beta-Galactosidase
4.
Nanotechnology ; 35(29)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38593758

RESUMO

To break the resolution limitation of traditional resists, more work is needed on non-chemically amplified resists (non-CARs). Non-CARs based on iodonium salt modified polystyrene (PS-I) were prepared with controllable molecular weight and structure. The properties of the resist can be adjusted by the uploading of iodonium salts on the polymer chain, the materials with a higher proportion of iodonium salts show better lithography performance. By comparing contrast curves and quality of the lithographic patterns, the optimum developing condition of 4-methyl-2-pentanone and ethyl alcohol (v:v = 1:7) was selected. The high-resolution stripes of 15 nm half-pitch (HP) can be achieved by PS-I0.58in e-beam lithography (EBL). PS-I0.58shows the advanced lithography performance in the patterns of 16 nm HP and 18 nm HP stripes with low line edge roughness (3.0 nm and 2.4 nm). The resist shows excellent potential for further pattern transfer, the etch selectivity of resist PS-I0.58to the silicon was close to 12:1. The lithographic mechanism of PS-I was investigated by experimental and theoretical calculation, which indicates the polarity of materials changes results in the solubility switch. This work provides a new option and useful guidelines for the development of high-resolution resist.

5.
BMC Med Imaging ; 24(1): 148, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886638

RESUMO

BACKGROUND: Preoperative discrimination between non-muscle-invasive bladder cancer (NMIBC) and the muscle invasive bladder cancer (MIBC) is a determinant of management. The purpose of this research is to employ radiomics to evaluate the diagnostic value in determining muscle invasiveness of compressed sensing (CS) accelerated 3D T2-weighted-SPACE sequence with high resolution and short acquisition time. METHODS: This prospective study involved 108 participants who underwent preoperative 3D-CS-T2-weighted-SPACE, 3D-T2-weighted-SPACE and T2-weighted sequences. The cohort was divided into training and validation cohorts in a 7:3 ratio. In the training cohort, a Rad-score was constructed based on radiomic features selected by intraclass correlation coefficients, pearson correlation coefficient and least absolute shrinkage and selection operator . Multivariate logistic regression was used to develop a nomogram combined radiomics and clinical indices. In the validation cohort, the performances of the models were evaluated by ROC, calibration, and decision curves. RESULTS: In the validation cohort, the area under ROC curve of 3D-CS-T2-weighted-SPACE, 3D-T2-weighted-SPACE and T2-weighted models were 0.87(95% confidence interval (CI):0.73-1.00), 0.79(95%CI:0.63-0.96) and 0.77(95%CI:0.60-0.93), respectively. The differences in signal-to-noise ratio and contrast-to-noise ratio between 3D-CS-T2-weighted-SPACE and 3D-T2-weighted-SPACE sequences were not statistically significant(p > 0.05). While the clinical model composed of three clinical indices was 0.74(95%CI:0.55-0.94) and the radiomics-clinical nomogram model was 0.88(95%CI:0.75-1.00). The calibration curves confirmed high goodness of fit, and the decision curve also showed that the radiomics model and combined nomogram model yielded higher net benefits than the clinical model. CONCLUSION: The radiomics model based on compressed sensing 3D T2WI sequence, which was acquired within a shorter acquisition time, showed superior diagnostic efficacy in muscle invasion of bladder cancer. Additionally, the nomogram model could enhance the diagnostic performance.


Assuntos
Imageamento Tridimensional , Invasividade Neoplásica , Neoplasias da Bexiga Urinária , Humanos , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Neoplasias da Bexiga Urinária/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Invasividade Neoplásica/diagnóstico por imagem , Estudos Prospectivos , Imageamento Tridimensional/métodos , Idoso , Imageamento por Ressonância Magnética/métodos , Curva ROC , Nomogramas , Radiômica
6.
Angew Chem Int Ed Engl ; : e202415927, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39485640

RESUMO

Asymmetric de novo synthesis of benzocyclobutenes (BCBs) via catalytic intermolecular reaction is highly desired for efficient access to this important class of compounds, yet such a strategy remains unmet challenge. Here, we report a Pd/Pyrox-catalyzed asymmetric [2+2] annulation between arylboronic acids and functionalized alkenes, providing an unprecedented efficient protocol to access various enantio-enriched BCBs in a modular and versatile manner under mild conditions. A broad substrate scope with excellent enantioselectivity has been achieved under the current protocol. The isolation and characterization of the key chiral palladacycle intermediate, together with DFT calculations, provides strong evidence for the catalytic pathway including an enantiodetermining arylpalladation step.

7.
J Am Chem Soc ; 145(9): 5007-5016, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36802615

RESUMO

We present an enantioconvergent access to chiral N-heterocycles directly from simple racemic diols and primary amines, through a highly economical borrowing hydrogen annulation. The identification of a chiral amine-derived iridacycle catalyst was the key for achieving high efficiency and enantioselectivity in the one-step construction of two C-N bonds. This catalytic method enabled a rapid access to a wide range of diversely substituted enantioenriched pyrrolidines including key precursors to valuable drugs such as aticaprant and MSC 2530818.

8.
Phys Rev Lett ; 131(26): 266101, 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38215382

RESUMO

The Grüneisen parameter (γ) is crucial for determining many thermal properties, including the anharmonic effect, thermostatistics, and equation of state of materials. However, the isentropic adiabatic compression conditions required to measure the Grüneisen parameter under high pressure are difficult to achieve. Thus, direct experimental Grüneisen parameter data in a wide range of pressures is sparse. In this work, we developed a new device that can apply pressure (up to tens of GPa) with an extremely short time of about 0.5 ms, confidently achieving isentropic adiabatic compression. Then, we applied our new technique to sodium chloride and measured its Grüneisen parameter, which conforms to previous theoretical predictions. According to our obtained sodium chloride Grüneisen parameters, the calculated Hugoniot curve of the NaCl B1 phase appears up to 20 GPa and 960 K, which compares very well with the shock compression experimental data by Fritz et al. and other calculation works. Our results suggest that this new method can reliably measure the Grüneisen parameter of even more materials, which is significant for researching the equation of state in substances.

9.
J Magn Reson Imaging ; 58(1): 258-269, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36300676

RESUMO

BACKGROUND: Whether bladder cancer (BCa) invades muscle is a determinant of management. However, the accuracy of preoperative diagnosis of muscle invasion is not satisfactory. PURPOSE: To investigate the value of multi-sequence and multi-regional magnetic resonance imaging (MRI)-based radiomics nomogram for assessing muscle invasion of BCa. STUDY TYPE: Retrospective. POPULATION: 342 BCa patients, divided into a training set (239 cases), a validation set (68 cases), and a test set (35 cases). FIELD STRENGTH/SEQUENCE: 3.0 T/T2 -weighted image, diffusion-weighted imaging, and dynamic contrast-enhanced imaging. ASSESSMENT: Patients were divided into muscle-invasive (79 cases) and non-muscle-invasive (263 cases). Two radiologists delineated the whole tumor, tumor body, and muscle layer of BCa, respectively, and extracted radiomic features. STATISTICAL TESTS: Recursive feature elimination, Pearson correlation coefficient, logistic regression, least absolute shrinkage and selection operator (Lasso) regression analysis, and 5-fold cross-validation were used to screen features and build a radiomics model. The clinical data were collected to construct a clinical model and a radiomics-clinical nomogram. RESULTS: 23,688 features were extracted. After screening, the radiomics scoring model was constructed using nine radiomics features with area under curve (AUC) values of 0.933, 0.913, and 0.931 in the training, validation, and test sets, respectively. The clinical model was constructed using five clinical independent risk factors; the AUC values in the training, validation, and test set were 0.876, 0.859, and 0.824, respectively. After logistic regression analysis, the AUC values of the radiomics-clinical nomogram were made up of four clinical independent risk factors and radiomics scores were 0.955, 0.922, and 0.935 for the training, validation, and test sets, respectively. The DeLong test between clinical model and radiomics-clinical nomogram shows P < 0.001. CONCLUSION: Multi-sequence and multi-regional MRI-based radiomics models could effectively assess the state of BCa muscular invasion. The radiomics-clinical nomogram is superior to clinical model for assessing BCa muscular invasion. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY: Stage 2.


Assuntos
Nomogramas , Neoplasias da Bexiga Urinária , Humanos , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Neoplasias da Bexiga Urinária/patologia , Imagem de Difusão por Ressonância Magnética
10.
J Pharmacol Sci ; 151(2): 72-83, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36707181

RESUMO

Bone marrow-derived mesenchymal stem cells (MSCs) show antifibrotic activity in various chronic kidney diseases. Here, we aimed to investigate whether Calycosin (CA), a phytoestrogen, could enhance the antifibrotic activity of MSCs in primary tubular epithelial cells (PTECs) induced by TGF-ß1 and in a mouse model of unilateral ureteral obstruction (UUO). We found that MSCs treatment significantly inhibited fibrosis, and CA pretreatment enhanced the effects of MSCs on fibrosis in vitro. Consistent with the in vitro studies, MSCs alleviated tubular injury and renal fibrosis in mice after UUO, and CA-pretreated MSCs resulted in more significant improvements in tubular injury and renal fibrosis than MSCs after UUO. Moreover, MSCs treatment significantly inhibited necroptosis by repressing the elevation of MLKL, RIPK1, and RIPK3 in PTECs treated by TGF-ß1and in mice after UUO, and CA-pretreated MSCs were superior to MSCs in alleviating necroptosis. MSCs significantly reduced TNF-α and TNFR1 expression induced by TGF-ß1 in PTECs and inhibited TGF-ß1, TNF-α, and TNFR1 expression induced by UUO in mice. These effects of MSCs were significantly enhanced after CA pretreatment. Therefore, our results suggest that CA pretreatment enhances the antifibrotic activity of MSCs by inhibiting TGF-ß1/TNF-α/TNFR1 signaling-induced necroptosis.


Assuntos
Células-Tronco Mesenquimais , Insuficiência Renal Crônica , Obstrução Ureteral , Camundongos , Animais , Obstrução Ureteral/complicações , Obstrução Ureteral/terapia , Fator de Crescimento Transformador beta1/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Necroptose , Insuficiência Renal Crônica/metabolismo , Fibrose , Rim/patologia
11.
Sensors (Basel) ; 23(11)2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37299818

RESUMO

Changes in pig behavior are crucial information in the livestock breeding process, and automatic pig behavior recognition is a vital method for improving pig welfare. However, most methods for pig behavior recognition rely on human observation and deep learning. Human observation is often time-consuming and labor-intensive, while deep learning models with a large number of parameters can result in slow training times and low efficiency. To address these issues, this paper proposes a novel deep mutual learning enhanced two-stream pig behavior recognition approach. The proposed model consists of two mutual learning networks, which include the red-green-blue color model (RGB) and flow streams. Additionally, each branch contains two student networks that learn collaboratively to effectively achieve robust and rich appearance or motion features, ultimately leading to improved recognition performance of pig behaviors. Finally, the results of RGB and flow branches are weighted and fused to further improve the performance of pig behavior recognition. Experimental results demonstrate the effectiveness of the proposed model, which achieves state-of-the-art recognition performance with an accuracy of 96.52%, surpassing other models by 2.71%.


Assuntos
Cruzamento , Redes Neurais de Computação , Humanos , Suínos , Animais , Movimento (Física)
12.
J Am Chem Soc ; 144(31): 14047-14052, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35916403

RESUMO

Directly editing an all-carbon quaternary carbon itself of nonstrained acyclic molecules remains underexploited despite the recent advances in the fields of both C-H and C-C bond activation. Herein, we report a palladium-catalyzed migrative carbofluorination of saturated amides enabled by the activation of both the C(sp3)-H and the Cquaternary-Cσ bonds. In this transformation, the α-quaternary carbon of Weinreb amides is converted to α-tertiary fluoride with concurrent migration of an aryl or an amido group from the α- to ß-carbon. DFT calculations indicate that the dyotropic rearrangement proceeds through an unusual anti-selective [2.1.0] bicyclic transition state. The reaction, compatible with a broad range of functional groups, is stereospecific and is applicable to the synthesis of enantioenriched products.


Assuntos
Amidas , Paládio , Amidas/química , Carbono/química , Catálise , Estrutura Molecular , Paládio/química
13.
Anal Chem ; 94(23): 8483-8488, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35635074

RESUMO

Herein, a series of triarylboron-based fluorescent probes were developed for distinguishing apoptosis from living cells and even necrosis. They also demonstrate high photosensitivity because they can produce detectable reactive oxygen species (ROS) under an ultra-low light power density (1.5 mW/cm2). By changing the peripheral groups to regulate the performance, we identified a multifunctional probe, TAB-6-amyl, which can be used not only for selectively imaging apoptosis but also for the targeted imaging of SKOV-3 cells in vitro and in vivo. It could further specifically induce the apoptosis of SKOV-3 cells under light irradiation. During the study, we also found that TAB-6-amyl can cross the blood-brain barrier (BBB). Therefore, another probe based on this kind of structure, TAB-5-M-1-cRGD, was constructed for the targeted imaging of brain glioma cells and inducing their apoptosis. This study offers some promising tools for apoptosis detection and tumor photodynamic therapy (PDT).


Assuntos
Glioma , Fotoquimioterapia , Apoptose , Linhagem Celular Tumoral , Corantes Fluorescentes/química , Glioma/diagnóstico por imagem , Glioma/patologia , Humanos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Espécies Reativas de Oxigênio
14.
Cell Mol Neurobiol ; 42(6): 1897-1908, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33712886

RESUMO

Neurons in the penumbra (the area surrounding ischemic tissue that consists of still viable tissue but with reduced blood flow and oxygen transport) may be rescued following stroke if adequate perfusion is restored in time. It has been speculated that post-stroke angiogenesis in the penumbra can reduce damage caused by ischemia. However, the mechanism for neovasculature formation in the brain remains unclear and vascular-targeted therapies for brain ischemia remain suboptimal. Here, we show that VEGFR1 was highly upregulated in pericytes after stroke. Knockdown of VEGFR1 in pericytes led to increased infarct area and compromised post-ischemia vessel formation. Furthermore, in vitro studies confirmed a critical role for pericyte-derived VEGFR1 in both endothelial tube formation and pericyte migration. Interestingly, our results show that pericyte-derived VEGFR1 has opposite effects on Akt activity in endothelial cells and pericytes. Collectively, these results indicate that pericyte-specific expression of VEGFR1 modulates ischemia-induced vessel formation and vascular integrity in the brain.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Circulação Cerebrovascular/fisiologia , Células Endoteliais/metabolismo , Humanos , Isquemia/metabolismo , Perfusão , Pericitos , Acidente Vascular Cerebral/metabolismo
15.
Analyst ; 147(4): 671-676, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35060584

RESUMO

The quantification of phenylalanine in clinical samples is essential for the diagnosis and treatment of neonatal phenylketonuria. In this report, an enzyme cascade strategy was proposed and a high-efficiency fluorescence assay was established for rapid and convenient phenylalanine quantification. The assay involves phenylalanine dehydrogenase for the quantitative metabolization of phenylalanine and the formation of NADH, as well as nitroreductase combining a nitroaromatic substrate for the fluorescent quantification of NADH and subsequently phenylalanine. The phenylalanine levels in clinical serum determined by this fluorescence assay are consistent with those from HPLC. This straightforward approach provides a versatile strategy for the development of cost-effective and convenient assays for mass screening and metabolite monitoring.


Assuntos
Fenilalanina , Fenilcetonúrias , Cromatografia Líquida de Alta Pressão , Ensaios Enzimáticos , Testes Hematológicos , Humanos , Recém-Nascido
16.
Analyst ; 147(23): 5264-5268, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36330961

RESUMO

NAD(P)H quinone oxidoreductase1 (NQO1) is a flavoenzyme that regulates the redox potential level in cells. Overexpression of NQO1 has been proven to be relevant to some malignant tumors. Herein a bioluminescent probe NQO1-Luc equipped with an NQO1-targeting group, trimethyl-locked quinone propionic acid (QPA), was constructed. The reduction of NQO1-Luc could be triggered by NQO1, resulting in the release of free D-luciferin, and concomitantly a bright bioluminescence emission. NQO1-Luc exhibits high selectivity and sensitivity toward NQO1 activity and the capability of distinguishing NQO1-overexpressing cells in vitro and in vivo, which offers a promising tool for investigations of NQO1 related biological processes including tumors in living organisms.


Assuntos
NAD(P)H Desidrogenase (Quinona) , Neoplasias , Humanos , NAD(P)H Desidrogenase (Quinona)/genética , Quinonas , Benzoquinonas
17.
Europace ; 24(3): 481-493, 2022 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-34516623

RESUMO

Cardiovascular diseases are the main cause of sudden cardiac death (SCD) in developed and developing countries. Inherited cardiac channelopathies are linked to 5-10% of SCDs, mainly in the young. Short QT syndrome (SQTS) is a rare inherited channelopathy, which leads to both atrial and ventricular tachyarrhythmias, syncope, and even SCD. International European Society of Cardiology guidelines include as diagnostic criteria: (i) QTc ≤ 340 ms on electrocardiogram, (ii) QTc ≤ 360 ms plus one of the follwing, an affected short QT syndrome pathogenic gene mutation, or family history of SQTS, or aborted cardiac arrest, or family history of cardiac arrest in the young. However, further evaluation of the QTc ranges seems to be required, which might be possible by assembling large short QT cohorts and considering genetic screening of the newly described pathogenic mutations. Since the mechanisms underlying the arrhythmogenesis of SQTS is unclear, optimal therapy for SQTS is still lacking. The disease is rare, unclear genotype-phenotype correlations exist in a bevy of cases and the absence of an international short QT registry limit studies on the pathophysiological mechanisms of arrhythmogenesis and therapy of SQTS. This leads to the necessity of experimental models or platforms for studying SQTS. Here, we focus on reviewing preclinical SQTS models and platforms such as animal models, heterologous expression systems, human-induced pluripotent stem cell-derived cardiomyocyte models and computer models as well as three-dimensional engineered heart tissues. We discuss their usefulness for SQTS studies to examine genotype-phenotype associations, uncover disease mechanisms and test drugs. These models might be helpful for providing novel insights into the exact pathophysiological mechanisms of this channelopathy and may offer opportunities to improve the diagnosis and treatment of patients with SQT syndrome.


Assuntos
Arritmias Cardíacas , Eletrocardiografia , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/tratamento farmacológico , Arritmias Cardíacas/genética , Eletrocardiografia/métodos , Frequência Cardíaca , Humanos , Fenótipo
18.
Int J Mol Sci ; 23(4)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35216067

RESUMO

Takotsubo syndrome (TTS) is identified as an acute severe ventricular systolic dysfunction, which is usually characterized by reversible and transient akinesia of walls of the ventricle in the absence of a significant obstructive coronary artery disease (CAD). Patients present with chest pain, ST-segment elevation or ischemia signs on ECG and increased troponin, similar to myocardial infarction. Currently, the known mechanisms associated with the development of TTS include elevated levels of circulating plasma catecholamines and their metabolites, coronary microvascular dysfunction, sympathetic hyperexcitability, inflammation, estrogen deficiency, spasm of the epicardial coronary vessels, genetic predisposition and thyroidal dysfunction. However, the real etiologic link remains unclear and seems to be multifactorial. Currently, the elusive pathogenesis of TTS and the lack of optimal treatment leads to the necessity of the application of experimental models or platforms for studying TTS. Excessive catecholamines can cause weakened ventricular wall motion at the apex and increased basal motion due to the apicobasal adrenoceptor gradient. The use of beta-blockers does not seem to impact the outcome of TTS patients, suggesting that signaling other than the beta-adrenoceptor-associated pathway is also involved and that the pathogenesis may be more complex than it was expected. Herein, we review the pathophysiological mechanisms related to TTS; preclinical TTS models and platforms such as animal models, human-induced pluripotent stem cell-derived cardiomyocyte (hiPSC-CM) models and their usefulness for TTS studies, including exploring and improving the understanding of the pathomechanism of the disease. This might be helpful to provide novel insights on the exact pathophysiological mechanisms and may offer more information for experimental and clinical research on TTS.


Assuntos
Cardiomiopatia de Takotsubo/patologia , Animais , Humanos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Receptores Adrenérgicos/metabolismo , Transdução de Sinais/fisiologia , Cardiomiopatia de Takotsubo/metabolismo
19.
Stroke ; 52(3): 811-820, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33567874

RESUMO

BACKGROUND AND PURPOSE: This study aimed to analyze the impact of baseline posterior circulation Acute Stroke Prognosis Early Computed Tomography Score (pc-ASPECTS) on the efficacy and safety of endovascular therapy (EVT) for patients with acute basilar artery occlusion. METHODS: The BASILAR was a nationwide prospective registry of consecutive patients with a symptomatic and radiologically confirmed acute basilar artery occlusion within 24 hours of symptom onset. We estimated the effect of standard medical therapy alone (SMT group) versus SMT plus EVT (EVT group) for patients with documented pc-ASPECTS on noncontrast CT, both as a categorical (0-4 versus 5-7 versus 8-10) and as a continuous variable. The primary outcomes included favorable functional outcomes (modified Rankin Scale ≤3) at 90 days and mortality within 90 days. RESULTS: In total, 823 cases were included: 468 with pc-ASPECTS 8 to 10 (SMT: 71; EVT: 397), 317 with pc-ASPECTS 5 to 7 (SMT: 85; EVT: 232), and 38 with pc-ASPECTS 0 to 4 (SMT: 13; EVT: 25). EVT was associated with higher rate of favorable outcomes (adjusted relative risk with 95% CI, 4.35 [1.30-14.48] and 3.20 [1.68-6.09]; respectively) and lower mortality (60.8% versus 77.6%, P=0.005 and 35.0% versus 66.2%, P<0.001; respectively) than SMT in the pc-ASPECTS 5 to 7 and 8 to 10 subgroups. Continuous benefit curves also showed the superior efficacy and safety of EVT over SMT in patients with pc-ASPECTS ≥5. Furthermore, the prognostic effect of onset to puncture time on favorable outcome with EVT was not significant after adjustment for pc-ASPECTS (adjusted odds ratio, 0.98 [95% CI, 0.94-1.02]). CONCLUSIONS: Patients of basilar artery occlusion with pc-ASPECTS ≥5 could benefit from EVT. The baseline pc-ASPECTS appears more important for decision making and predicting prognosis than time to EVT. Registration: URL: http://www.chictr.org.cn. Unique identifier: ChiCTR1800014759.


Assuntos
Artéria Basilar/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Idoso , Arteriopatias Oclusivas/complicações , Procedimentos Endovasculares/métodos , Humanos , Pessoa de Meia-Idade , Variações Dependentes do Observador , Prognóstico , Estudos Prospectivos , Sistema de Registros , Trombectomia/métodos , Resultado do Tratamento , Insuficiência Vertebrobasilar/complicações
20.
J Org Chem ; 86(23): 16573-16581, 2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34726916

RESUMO

Enantioselective ring-contraction reactions have not been widely reported. We have developed an enantioselective ring contraction of 5,6-dihydro-2H-benzo[b][1,4]oxazocines, affording enantiomerically enriched 3,4-dihydro-2H-1,4-benzoxazine derivatives as single regioisomers. An acidic additive is necessary in order to obtain the products with good yields and enantiomeric ratios (up to 93% yield, 98:2 er). The reaction was successfully performed on a gram scale, and the products can be derivatized easily.


Assuntos
Benzoxazinas , Catálise , Estereoisomerismo
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