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1.
Mol Cell ; 79(3): 443-458.e7, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32649883

RESUMO

Despite the prominent role of TDP-43 in neurodegeneration, its physiological and pathological functions are not fully understood. Here, we report an unexpected role of TDP-43 in the formation of dynamic, reversible, liquid droplet-like nuclear bodies (NBs) in response to stress. Formation of NBs alleviates TDP-43-mediated cytotoxicity in mammalian cells and fly neurons. Super-resolution microscopy reveals distinct functions of the two RRMs in TDP-43 NB formation. TDP-43 NBs are partially colocalized with nuclear paraspeckles, whose scaffolding lncRNA NEAT1 is dramatically upregulated in stressed neurons. Moreover, increase of NEAT1 promotes TDP-43 liquid-liquid phase separation (LLPS) in vitro. Finally, we discover that the ALS-associated mutation D169G impairs the NEAT1-mediated TDP-43 LLPS and NB assembly, causing excessive cytoplasmic translocation of TDP-43 to form stress granules, which become phosphorylated TDP-43 cytoplasmic foci upon prolonged stress. Together, our findings suggest a stress-mitigating role and mechanism of TDP-43 NBs, whose dysfunction may be involved in ALS pathogenesis.


Assuntos
Esclerose Lateral Amiotrófica/genética , Proteínas de Ligação a DNA/genética , Corpos de Inclusão Intranuclear/metabolismo , Neurônios/metabolismo , RNA Longo não Codificante/genética , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Animais Geneticamente Modificados , Arsenitos/farmacologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Córtex Cerebral/ultraestrutura , Grânulos Citoplasmáticos/efeitos dos fármacos , Grânulos Citoplasmáticos/metabolismo , Grânulos Citoplasmáticos/ultraestrutura , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Drosophila melanogaster , Regulação da Expressão Gênica , Células HEK293 , Células HeLa , Humanos , Corpos de Inclusão Intranuclear/efeitos dos fármacos , Corpos de Inclusão Intranuclear/ultraestrutura , Camundongos , Mutação , Neurônios/efeitos dos fármacos , Neurônios/ultraestrutura , Cultura Primária de Células , Transporte Proteico/efeitos dos fármacos , RNA Longo não Codificante/metabolismo , Transdução de Sinais , Estresse Fisiológico
2.
Ren Fail ; 46(1): 2347446, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38695335

RESUMO

This study is intended to explore the effect of hypoxia-inducible factor-1α (HIF-1α) activation on lipid accumulation in the diabetic kidney. A type 1 diabetic rat model was established by STZ intraperitoneal injection. Cobalt chloride (CoCl2) and YC-1 were used as the HIF-1α activator and antagonist, respectively. CoCl2 treatment significantly increased HIF-1α expression, accelerated lipid deposition, and accelerated tubular injury in diabetic kidneys. In vitro, CoCl2 effectively stabilized HIF-1α and increased its transportation from the cytoplasm to the nucleus, which was accompanied by significantly increased lipid accumulation in HK-2 cells. Furthermore, results obtained in vivo showed that HIF-1α protein expression in the renal tubules of diabetic rats was significantly downregulated by YC-1 treatment. Meanwhile, lipid accumulation in the tubules of the DM + YC-1 group was markedly decreased in comparison to the DM + DMSO group. Accordingly, PAS staining revealed that the pathological injury caused to the tubular epithelial cells was alleviated by YC-1 treatment. Furthermore, the blood glucose level, urine albumin creatinine ratio, and NAG creatinine ratio in the DM + YC-1 group were significantly decreased compared to the DM + DMSO group. Moreover, the protein expression levels of transforming growth factor ß1 (TGF-ß1) and connective tissue growth factor (CTGF) in diabetic kidneys were decreased by YC-1 treatment. Our findings demonstrate that the activation of HIF-1α contributed to interstitial injury in a rat model of diabetic nephropathy and that the underlying mechanism involved the induction of lipid accumulation.


Assuntos
Cobalto , Diabetes Mellitus Experimental , Nefropatias Diabéticas , Subunidade alfa do Fator 1 Induzível por Hipóxia , Animais , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Ratos , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Masculino , Ratos Sprague-Dawley , Túbulos Renais/patologia , Túbulos Renais/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Indazóis/farmacologia , Humanos , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Linhagem Celular
3.
Angew Chem Int Ed Engl ; : e202408551, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858167

RESUMO

Heat-activated second harmonic generation (SHG) switching materials are gaining interest for their ability to switch between SHG on and off states, offering potential in optoelectronic applications. The novel nonlinear optical (NLO) switch, (C5H6NO)+(CH3SO3)- (4-hydroxypyridinium methylsulfonate, 4HPMS), is a near-room-temperature thermal driven material with a strong SHG response (3.3 × KDP), making it one of the most potent heat-stimulated NLO switches. It offers excellent contrast of 13 and a high laser-induced damage threshold (2.5 × KDP), with reversibility > 5 cycles. At 73 °C, 4HPMS transitions from the noncentrosymmetric Pna21 room temperature phase (RTP) to the centrosymmetric P21/c phase, caused by the rotation of the (C5H6NO)+ and (CH3SO3)- due to partially thermal breaking of intermolecular hydrogen bonds. The reverse phase change exhibits a large 50 °C thermal hysteresis. Density functional theory (DFT) calculations show that (C5H6NO)+ primarily dictates both the SHG coefficient (dij) and birefringence (∆n(Zeiss) = 0.216 vs ∆n(cal.) = 0.202 at 546 nm; Δn(Immersion) = 0.210 vs ∆n(cal.) = 0.198 at 589.3 nm), while the band gap (Eg) is influenced synergistically by (C5H6NO)+ and (CH3SO3)-. Additionally, 4HPMS-RTP also exhibits mechanochromism upon grinding as well as an aggregation-enhanced emission in a mixture of acetone and water.

4.
Neurobiol Dis ; 185: 106249, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37536386

RESUMO

Epilepsy is one of most common chronic neurological disorders, and the antiseizure medications developed by targeting neurocentric mechanisms have not effectively reduced the proportion of patients with drug-resistant epilepsy. Further exploration of the cellular or molecular mechanism of epilepsy is expected to provide new options for treatment. Recently, more and more researches focus on brain network components other than neurons, among which microglia have attracted much attention for their diverse biological functions. As the resident immune cells of the central nervous system, microglia have highly plastic transcription, morphology and functional characteristics, which can change dynamically in a context-dependent manner during the progression of epilepsy. In the pathogenesis of epilepsy, highly reactive microglia interact with other components in the epileptogenic network by performing crucial functions such as secretion of soluble factors and phagocytosis, thus continuously reshaping the landscape of the epileptic brain microenvironment. Indeed, microglia appear to be both pro-epileptic and anti-epileptic under the different spatiotemporal contexts of disease, rendering interventions targeting microglia biologically complex and challenging. This comprehensive review critically summarizes the pathophysiological role of microglia in epileptic brain homeostasis alterations and explores potential therapeutic or modulatory targets for epilepsy targeting microglia.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia , Humanos , Microglia/patologia , Epilepsia/patologia , Encéfalo/patologia , Neurônios/patologia
5.
Mol Biol Evol ; 39(2)2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-34893856

RESUMO

Domestic sheep and their wild relatives harbor substantial genetic variants that can form the backbone of molecular breeding, but their genome landscapes remain understudied. Here, we present a comprehensive genome resource for wild ovine species, landraces and improved breeds of domestic sheep, comprising high-coverage (∼16.10×) whole genomes of 810 samples from 7 wild species and 158 diverse domestic populations. We detected, in total, ∼121.2 million single nucleotide polymorphisms, ∼61 million of which are novel. Some display significant (P < 0.001) differences in frequency between wild and domestic species, or are private to continent-wide or individual sheep populations. Retained or introgressed wild gene variants in domestic populations have contributed to local adaptation, such as the variation in the HBB associated with plateau adaptation. We identified novel and previously reported targets of selection on morphological and agronomic traits such as stature, horn, tail configuration, and wool fineness. We explored the genetic basis of wool fineness and unveiled a novel mutation (chr25: T7,068,586C) in the 3'-UTR of IRF2BP2 as plausible causal variant for fleece fiber diameter. We reconstructed prehistorical migrations from the Near Eastern domestication center to South-and-Southeast Asia and found two main waves of migrations across the Eurasian Steppe and the Iranian Plateau in the Early and Late Bronze Ages. Our findings refine our understanding of genome variation as shaped by continental migrations, introgression, adaptation, and selection of sheep.


Assuntos
Genoma , Carneiro Doméstico , Animais , Ásia , Europa (Continente) , Variação Genética , Irã (Geográfico) , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Ovinos/genética , Carneiro Doméstico/genética
6.
BMC Med ; 21(1): 292, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37545008

RESUMO

BACKGROUND: Folic acid (FA) supplementation is associated with a lower risk of the neural tube and heart defects and is recommended for women of childbearing age. Although there are detailed recommendations, differences in the initiation time and duration of FA supplementation remain poorly studied. METHODS: A multicentre prospective study of 17,713 women was conducted. The incidence of congenital malformations in women taking a recommended dosage (e.g. 0.4 or 0.8 mg/day) of FA was compared with that in women without supplementation. The predicted probability of malformations by the initiation time and duration of FA use was estimated to determine optimal options. RESULTS: Periconceptional FA supplementation was associated with a lower and insignificant risk of congenital malformations (1.59% vs. 2.37%; odds ratio [OR] 0.69; 95% confidence interval [CI]: 0.44-1.08), heart defects (3.8 vs. 8.0 per 1000 infants; OR, 0.47; 0.21-1.02), and neural tube defects (7.0 vs. 11.5 per 10,000 infants; OR, 0.64; 0.08-5.15). FA use after pregnancy provided greater protection against total malformations. Statistically significant associations were found in women who initiated FA supplementation in the first month of gestation (OR, 0.55; 95% CI: 0.33-0.91) and in those who supplemented for 1 to 2 months (OR, 0.59; 95% CI: 0.36-0.98). Similar results were found for heart defects. The optimal initiation time was 1.5 (optimal range: 1.1 to 1.9) months before pregnancy and a duration of 4.0 (3.7 to 4.4) months was reasonable to achieve the lowest risk of congenital malformations. Heart defect prevention required an earlier initiation (2.2 vs. 1.1 months before pregnancy) and a longer duration (4.7 vs. 3.7 months) than the prevention of other malformations. CONCLUSIONS: The timely initiation of FA supplementation for gestation was associated with a decreased risk of congenital malformations, which was mainly attributed to its protection against heart defects. The initiation of FA supplementation 1.5 months before conception with a duration of 4 months is the preferred option for congenital malformation prevention. TRIAL REGISTRATION: Chictr.org.cn identifier: ChiCTR-SOC-17010976.


Assuntos
Ácido Fólico , Complexo Vitamínico B , Gravidez , Lactente , Feminino , Humanos , Cuidado Pré-Concepcional , Estudos Prospectivos , Suplementos Nutricionais
7.
Anal Bioanal Chem ; 415(16): 3255-3264, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37071141

RESUMO

We demonstrate wrinkle-bioinspired flexible SERS sensor covered by silver nanowire (AgNWs) network for the detection of pesticide molecules. Compared with the silver film deposition substrates, the wrinkle-bioinspired AgNWs SERS substrates show stronger SERS effect, which were attributed to the electromagnetic field enhancement posed by the relatively high density "hot spots" of AgNWs. In order to investigate the adsorption performance of wrinkle-bioinspired flexible sensors, we measured the corresponding contact angles of AgNWs on the substrate surfaces before and after plasma treatment and found that the AgNWs treated with plasma are more hydrophilic than that without plasma treatment. Additionally, the wrinkle-bioinspired SERS sensors show different SERS activities under different tensile strain, and the 10-6 mol/L concentration of Rhodamine dye (R6G) molecules can be detected by portable Raman spectra, reducing greatly detection cost. The surface plasmon resonance of AgNWs is induced by adjusting the deformation of AgNWs substrate, enhancing the SERS signal. This reliability of wrinkle-bioinspired SERS sensors is further verified by in situ detection of pesticide molecules.


Assuntos
Nanopartículas Metálicas , Nanofios , Praguicidas , Praguicidas/análise , Prata/química , Análise Espectral Raman , Reprodutibilidade dos Testes , Nanopartículas Metálicas/química
8.
Eur J Nutr ; 62(3): 1239-1251, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36502467

RESUMO

PURPOSE: We examined the association between whole grain and refined grain intake with all-cause, cancer and cardiovascular disease (CVD) mortality using the data from the Guangzhou Biobank Cohort Study. METHODS: 19,597 participants aged 50+ years were recruited from 2003 to 2006 and followed-up until April 2021. Multivariable Cox regression was used to calculate hazard radios (HRs) and 95% confidence intervals (CIs). Substitution analysis was used to replace a serving (50 g/day) of whole grain with a serving of refined grain. RESULTS: During 286,821 person-years of follow-up, 4385 deaths occurred, including 1450 from cancer, 1678 from CVD and 1257 from other causes. Compared with never whole grain intake, the highest intake category of whole grain (> 300 g/week) was associated with lower risk of all-cause (HR 0.90, 95% CI 0.82-0.98) and CVD mortality (HR 0.85, 0.74-0.98). Compared with the low-intake category of refined grain (< 500 g/day), the highest intake category (> 900 g/week) was associated with a lower risk of cancer mortality (HR 0.76, 0.62-0.95), but a higher risk of CVD mortality (HR 1.25, 1.03-1.51). No significant associations were found between whole grain intake and cancer mortality nor refined grain and all-cause mortality. The HRs of all-cause, cancer and CVD mortality substituting a serving of whole grain for refined grain were 0.96 (0.94-0.99), 1.01 (0.99-1.02) and 0.95 (0.90-0.99), respectively. CONCLUSION: We have first shown that in older Chinese, whole grain intake was associated with lower risk of all-cause and CVD mortality. Our results suggest that intake of whole grain of at least 300 g/week and refined grain of ≤ 900 g/day might be suitable for older Asian. Substituting 50 g/day of whole grain for refined grain was associated with a 4-5% lower risk of all-cause and CVD mortality.


Assuntos
Doenças Cardiovasculares , Neoplasias , Humanos , Idoso , Grão Comestível , Estudos de Coortes , Seguimentos , Estudos Prospectivos , População do Leste Asiático , Fatores de Risco , Dieta
9.
Acta Obstet Gynecol Scand ; 102(6): 735-743, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37073619

RESUMO

INTRODUCTION: The potential teratogenic risk of traditional Chinese medicine (TCM) is of widespread concern; however, related evidence is largely absent in humans. This study aimed to compare the prevalence of congenital malformations between pregnant women with and without TCM exposure. MATERIAL AND METHODS: This was a multicenter prospective cohort study of 17 713 women who participated in a survey on periconceptional TCM exposure. Primary outcome was congenital malformations diagnosed from a survey conducted on the day 42 after delivery. RESULTS: A total of 16 751 pregnant women with 273 congenital malformations were included in the analysis. Fetuses exposed to TCM had an increased risk of congenital malformations compared to those without exposure (odds ratio [OR] 2.10; 95% confidence interval [CI] 1.09-4.02) after controlling for potential confounders. There were significant associations with congenital malformations in women with early pregnant exposure (OR 2.04, 95% CI 1.00-4.20) and for those who received ≥2 TCM formulas (OR 5.84, 95% CI 1.44-23.65). Pre-pregnancy TCM exposure was significantly associated with an increased risk of congenital heart defects (OR 12.69; 95% CI 3.01-53.51). CONCLUSIONS: Periconceptional TCM exposure is associated with an increased risk of congenital malformation. This effect was cumulative and sensitive to periconceptional age. Therefore, TCM deserves more attention and should be used cautiously for pregnant women and those trying to become pregnant.


Assuntos
Anormalidades Induzidas por Medicamentos , Anormalidades Congênitas , Cardiopatias Congênitas , Complicações na Gravidez , Feminino , Gravidez , Humanos , Estudos Prospectivos , Medicina Tradicional Chinesa/efeitos adversos , Cardiopatias Congênitas/epidemiologia , Cardiopatias Congênitas/complicações , Exposição Materna/efeitos adversos , Anormalidades Induzidas por Medicamentos/epidemiologia , Anormalidades Induzidas por Medicamentos/etiologia , Anormalidades Congênitas/epidemiologia , Anormalidades Congênitas/etiologia
10.
Immun Ageing ; 20(1): 27, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37340309

RESUMO

TDP-43 is an important DNA/RNA-binding protein that is associated with age-related neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD); however, its pathomechanism is not fully understood. In a transgenic RNAi screen using Drosophila as a model, we uncovered that knockdown (KD) of Dsor1 (the Drosophila MAPK kinase dMEK) suppressed TDP-43 toxicity without altering TDP-43 phosphorylation or protein levels. Further investigation revealed that the Dsor1 downstream gene rl (dERK) was abnormally upregulated in TDP-43 flies, and neuronal overexpression of dERK induced profound upregulation of antimicrobial peptides (AMPs). We also detected a robust immune overactivation in TDP-43 flies, which could be suppressed by downregulation of the MEK/ERK pathway in TDP-43 fly neurons. Furthermore, neuronal KD of abnormally increased AMPs improved the motor function of TDP-43 flies. On the other hand, neuronal KD of Dnr1, a negative regulator of the Drosophila immune deficiency (IMD) pathway, activated the innate immunity and boosted AMP expression independent of the regulation by the MEK/ERK pathway, which diminished the mitigating effect of RNAi-dMEK on TDP-43 toxicity. Finally, we showed that an FDA-approved MEK inhibitor trametinib markedly suppressed immune overactivation, alleviated motor deficits and prolonged the lifespan of TDP-43 flies, but did not exhibit a lifespan-extending effect in Alzheimer disease (AD) or spinocerebellar ataxia type 3 (SCA3) fly models. Together, our findings suggest an important role of abnormal elevation of the MEK/ERK signaling and innate immunity in TDP-43 pathogenesis and propose trametinib as a potential therapeutic agent for ALS and other TDP-43-related diseases.

11.
J Org Chem ; 87(21): 14194-14207, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36265020

RESUMO

An acyl lactonization of alkenes with aldehydes under visible-light photoredox catalysis is described. With the protocol, a broad scope of alkenoic acids and aldehydes could be compatible and good functional group tolerance is obtained. A series of acyl lactones are obtained with isolated yields ranging from 50-95%. Mechanistic studies revealed that the transformation should proceed via a radical chain process.


Assuntos
Aldeídos , Alcenos , Lactonas , Estrutura Molecular , Catálise
12.
Bioorg Med Chem ; 60: 116705, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35286954

RESUMO

Isoquinoline alkaloid displays significant anti-gastric cancer effects due to its unique structure, which is attracting more and more attention for the development of anti-gastric cancer drugs. In this study, we explore the active components against gastric cancer from the Tibetan Medicine Corydalis hendersonii Hemsl, which is rich in isoquinoline alkaloids. 14 compounds including 2 previously undescribed natural products were obtained. Interestingly, an new active compound displays potent anti-gastric cancer activity. After accomplishing the total syntheses of the active compound and its derivatives, the anti-gastric cancer activity of the active compound was further investigated. In vitro experiments revealed that the active compound significantly attenuated the proliferative capacity, caused G2/M phase arrest, inhibited the cell migration and invasion, and induced cell apoptosis. Mechanistically, the active compound could increase the Bax/Bcl-2 ratio, elevate cytochrome c in the cytosol, and activate caspase-9/3, along with inactivating the upstream PI3K/Akt/mTOR signaling pathway. In addition, the active compound could also cause gastric cancer cell death by inhibiting topoisomerase I activity. More importantly, the anti-gastric cancer activity of the active compound was confirmed in MGC-803 xenograft nude mice in vivo. This work not only promotes the exploitation of Corydalis hendersonii Hemsl., but also provides some experience for discovering new entities from natural sources.


Assuntos
Alcaloides , Corydalis , Neoplasias Gástricas , Alcaloides/química , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Animais , Apoptose , Corydalis/química , Humanos , Isoquinolinas/química , Isoquinolinas/farmacologia , Isoquinolinas/uso terapêutico , Camundongos , Camundongos Nus , Fosfatidilinositol 3-Quinases , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo
13.
Support Care Cancer ; 30(6): 5221-5229, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35260921

RESUMO

BACKGROUND: The study aimed to compare the predictive values of three widely used nutritional assessment methods, body mass index (BMI), Nutritional Risk Screening 2002 (NRS 2002), and the prognostic nutritional index (PNI), for different clinical prognostic indicators of ovarian cancer patients. METHODS: Patients diagnosed with ovarian cancer treated in our hospital between January 2017 and March 2019 were retrospectively included. The three nutritional assessment methods were assessed, and multivariable analysis was conducted to explore predictive factors for clinical prognoses. Receiver operating characteristic (ROC) curves and the area under the ROC curve (AUROC) were generated to evaluate the discriminative abilities of the three nutritional assessment tools. RESULTS: A total of 442 patients were recruited. Multivariable analysis revealed that the PNI value predicted 1-year death and 1-year recurrence and that both the NRS 2002 score and the PNI value predicted 30-day readmission (P < 0.05). For PNI, AUROCs were 0.834 for predicting 1-year death and 0.719 for 1-year recurrence prediction; for NRS, the AUROC was 0.820 2002 for predicting 30-day readmission. The optimal cutoff values that maximized the prognostic prediction ability were PNI values of 47.75 g/L and 50.40 g/L for 1-year death and 1-year recurrence, respectively, and an NRS 2002 score of 3 points for 30-day readmission following discharge. CONCLUSION: For ovarian cancer patients, the PNI is better at predicting 1-year death and 30-day readmission after discharge, and the NRS 2002 is superior for predicting 1-year recurrence.


Assuntos
Avaliação Nutricional , Neoplasias Ovarianas , Feminino , Humanos , Estado Nutricional , Neoplasias Ovarianas/diagnóstico , Prognóstico , Estudos Retrospectivos
14.
J Am Chem Soc ; 143(9): 3647-3654, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33646792

RESUMO

We herein report a novel semiorganic NLO material, (C5H6ON)+(H2PO4)-, 4HPP, showing promising excellent properties in the important solar-blind UV region where LAP and its deuterated form DLAP are the only commercialized semiorganic materials. For the first time, the 4-hydroxypyridine (4HP+, (C5H6ON)+) cation is identified as NLO active and how to eliminate the dipole-dipole interaction to avoid the unwanted center-symmetry-trap caused by the polar-induced susceptibility is well demonstrated. Remarkably, 4HPP exhibits competitive and even better properties compared with LAP that include better thermal stability (decomposition at 166 vs 112 °C of LAP); wider transparency range (0.26-1.50 µm); very strong SHG response (3 × KDP); a suitable large birefringence (Δncal = 0.25 vs 0.075 of LAP); and a high laser-induced damage threshold (2.2 × KDP). First-principles calculations show that the π-conjugated organic (4HP)+ cation governs the optical anisotropy, whereas the synergy of the organic and inorganic moieties dominates the SHG process. Our discovery points out a new path for the rational design of high performance semiorganic materials that require an acentric structure.

15.
J Org Chem ; 86(18): 12693-12704, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34491765

RESUMO

We report herein the facile and practical construction of α,ß-unsaturated ketones via rhodium-catalyzed direct acylation of vinylsilanes with readily available and abundant carboxylic acids. This protocol features access to a diverse array of synthetically useful functionalities with moderate to excellent yields. More importantly, the late-stage functionalization of pharmaceuticals was also realized with synthetically useful yield.

16.
J Org Chem ; 86(15): 10580-10590, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34314188

RESUMO

A copper-catalyzed intermolecular electrophilic amination of benzamides with O-benzoyl hydroxylamines was achieved with the assistance of an 8-aminoquinolyl group. With this protocol, good compatibility was observed for a variety of aryl amides and heteroaryl amides, and excellent tolerance with various functional groups was achieved. Significantly, the monoaminated product was overwhelmingly delivered under the simple reaction conditions. Preliminary mechanistic investigations suggested that a radical pathway should be excluded and C-H activation be potentially the rate-determining step.

17.
J Org Chem ; 86(17): 11998-12007, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34404211

RESUMO

A visible-light photoredox-catalyzed sulfonyl lactonization of unsaturated carboxylic acids with sulfonyl chlorides is described. This reaction features good functional group tolerance and a broad substrate scope, providing a simple and efficient protocol to access a wide range of sulfonyl lactones in high to excellent yields. Preliminary mechanistic investigations suggested that a free-radical pathway should be involved in the process.


Assuntos
Cloretos , Lactonas , Ácidos Carboxílicos , Catálise , Luz
18.
Support Care Cancer ; 29(8): 4209-4221, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33598736

RESUMO

OBJECTIVE: We sought to describe the short-term (1, 3, 6, 12 months) QoL changes after surgery for patients with gynecological malignancies in a meta-analysis. METHODS: We collected studies based on the PICOS (patients, intervention, comparison, outcome, and study design) framework (P: patients with gynecological malignancy; I: surgery; C: presurgery; O: QoL scores; S: randomized controlled trials, case-control studies, or cohort studies) in the Cochrane Library, MEDLINE, EMBASE, Web of Science, EBSCO, and China National Knowledge Infrastructure (CNKI) databases up to June 28, 2020. Then, two reviewers independently performed article screening, data extraction, and study quality evaluation. Stata 15.0 software was utilized for data analysis. RESULTS: Nine studies with 1476 patients were ultimately included. QoL in global health status improved until 12 months after surgery with a maximum improvement (6.99 [0.31, 13.68], P = 0.04), and QoL in emotional functioning reduced significantly until 12 months after surgery with a maximum reduction (14.87 [10.29, 19.45], P < 0.00001). All of the symptom scales were reduced significantly until 12 months postoperation, indicating quality of life improvement. There was a clinical reduction in QoL but symptom experience (-3.31 [-5.51, -1.12], P=0.003) at six months after surgery compared with baseline (presurgery), with only sexual worry being statistically significant (4.61 [0.95, 8.27], P=0.01). CONCLUSIONS: The recovery time varied among each dimension of the postoperative QoL of patients with gynecological malignancies; only a few functions and symptoms began to improve at 1 month postoperation and more at 12 months postoperation. Therefore, it is vitally important to develop extended care programs targeting the multidimensional aspects of QoL for patients with gynecological malignancies after surgery.


Assuntos
Neoplasias dos Genitais Femininos/psicologia , Qualidade de Vida/psicologia , Feminino , Humanos , Masculino , Período Pós-Operatório
19.
Child Dev ; 92(6): e1126-e1137, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34138465

RESUMO

A central theme of acculturative specificity is the heterogeneity of the immigrant experience. This study integrated this application of the Specificity Principle with intergenerational transmission models of self-regulation and identified both common and specific pathways in the self-regulatory development of Chinese American children in immigrant families (N = 169, Mage = 9.2 years). Consistent with intergenerational transmission models, results indicated associations between parents' and children's effortful control, with the mediation of these associations via authoritarian parenting. Parental education, family income, and children's bilingual proficiency were also uniquely associated with children's executive function and effortful control. Together, findings provide new directions for research with ethnic minority immigrant families, and underscore the utility of within-group approaches in advancing research on ethnic minority children's development.


Assuntos
Emigrantes e Imigrantes , Minorias Étnicas e Raciais , Criança , China , Etnicidade , Humanos , Grupos Minoritários , Relações Pais-Filho , Poder Familiar
20.
Chem Biodivers ; 18(11): e2100343, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34460996

RESUMO

One new siaresinolic acid saponin (1) and three new rotundic acid saponins (2-4) were isolated from the roots of Ilex centrochinensis. Their structures were confirmed by detailed analysis of standard spectroscopic data (IR, MS, 1D and 2D NMR). Compounds 1-4 exhibited anti-inflammatory activity by inhibiting nitric oxide production in a lipopolysaccharide-induced RAW264.7 cell inflammatory model. However, they showed no significant lipid-lowering activity against the production of triglycerides in the lipid-accumulation model of HepG2 cells induced by oleic acid.


Assuntos
Anti-Inflamatórios/farmacologia , Ilex/química , Óxido Nítrico/antagonistas & inibidores , Raízes de Plantas/química , Saponinas/farmacologia , Triterpenos/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Células Hep G2 , Humanos , Lipídeos/antagonistas & inibidores , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Camundongos , Óxido Nítrico/biossíntese , Células RAW 264.7 , Saponinas/química , Saponinas/isolamento & purificação , Triterpenos/química , Triterpenos/isolamento & purificação
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