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1.
Drug Des Devel Ther ; 15: 2805-2813, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34234412

RESUMO

Objective: The principal purpose of this study was to compare reproductive outcomes for stimulated cycles (STC) and hormone replacement cycles (HRC) for endometrial preparation before frozen-thawed embryo transfer (FET) in young women with polycystic ovary syndrome (PCOS). Methods: We conducted a retrospective study of 1434 FET cycles from January, 2017 to March, 2020 in our reproductive center, in which stimulated and hormone replacement cycles were used for endometrial preparation. Pregnancy outcomes of couples undergoing routine STC-FET or HRC-FET were analyzed by propensity score matching (PSM) and multivariable logistic regression analyses. Results: Data on 1234 HRC protocols (86% of the total) and 200 STC protocols (14%) were collected. After PSM, 199 patients were included in both groups, respectively. There was no significant difference in positive pregnancy rate (52.7% vs 54.8%, p=0.763), clinical pregnancy rate (51.8% vs 52.8%, p=0.841), live birth rate (45.2% vs 43.7%, p=0.762), pregnancy loss rate (9.7% vs 16.2%, p=0.164) and ectopic pregnancy rate (1.5% vs 0.5%, p=0.615) between STC and HRC protocols. Subsequent multivariate logistic regression analysis also yielded similar results. Conclusion: STC for endometrial preparation had similar pregnancy outcomes compared with HRC protocols. Evidence is available which shows that for young women with PCOS in preparation for FET, HRC could be a reasonable choice for patients who are unwilling to accept injections. However, STC may reduce unnecessary anxiety and operational costs and offer more flexibility for patients. Eventually, we must embrace the concepts of individualization, securitization, and optimization in the clinic.

2.
Nanotechnology ; 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34237709

RESUMO

Polyacrylonitrile /Ti3C2Tx MXene/silver nanoparticles fiber membranes with different silver nanoparticles contents and thickness of porous structure have been successfully prepared by electrospinning. Through the measurement of terahertz time domain spectrum, the shielding effect of the fiber membrane with 1% silver nanoparticles content can reach up to 12 dB. Moreover, the thickness of the spinning fiber membranes is controlled by adjusting the spinning time, so as to better analyse the influence of the thickness of the shielding performance in terahertz band. We attribute this excellent phenomenon to porous structure of the spun fiber membrane and combination of Ti3C2Tx MXene with few-layers and silver nanoparticles to increase the absorption and conductivity of the fiber membrane, thereby enhancing the shielding effect in terahertz range. Meanwhile, the prepared polyacrylonitrile / Ti3C2Tx MXene/ silver nanoparticles fiber membranes show good stability and little change in terahertz shielding effect after high temperature annealing. This may provide potential ideas about the development of high-performance terahertz shielding materials, which are of great significance of terahertz electromagnetic shielding.

5.
Cereb Cortex ; 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34240115

RESUMO

Previous functional magnetic resonance imaging (fMRI) studies have showed obesity (OB)-related alterations in intrinsic functional connectivity (FC) within and between different resting-state networks (RSNs). However, few studies have examined dynamic functional connectivity (DFC). Thus, we employed resting-state fMRI with independent component analysis (ICA) and DFC analysis to investigate the alterations in FC within and between RSNs in 56 individuals with OB and 46 normal-weight (NW) controls. ICA identified six RSNs, including basal ganglia (BG), salience network (SN), right executive control network/left executive control network, and anterior default-mode network (aDMN)/posterior default-mode network. The DFC analysis identified four FC states. OB compared with NW had more occurrences and a longer mean dwell time (MDT) in state 2 (positive connectivity of BG with other RSN) and also had higher FC of BG-SN in other states. Body mass index was positively correlated with MDT and FCs of BG-aDMN (state 2) and BG-SN (state 4). DFC analysis within more refined nodes of RSNs showed that OB had more occurrences and a longer MDT in state 1 in which caudate had positive connections with the other network nodes. The findings suggest an association between caudate-related and BG-related positive FC in OB, which was not revealed by traditional FC analysis, highlighting the utility of adding DFC to the more conventional methods.

6.
Magn Reson Med ; 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34231258

RESUMO

PURPOSE: The assessment of cellular energy metabolism is crucial for understanding myocardial physiopathology. Here, we conducted a pilot study to develop an alternative imaging approach for the assessment of myocardial energy metabolism. METHODS: We developed a deuterium MRSI method to noninvasively monitor the accumulation of deuterated downstream metabolites and deuterated water in rat hearts infused with deuterated glucose or acetate substrate on a 16.4 Tesla animal scanner. RESULTS: We found that the deuterated water accumulation rate and isotopic turnover rate of deuterated glutamate/glutamine via the tricarboxylic acid cycle and exchange in rat hearts were much higher when infused with acetate compared to that with glucose, demonstrating the myocardium substrate preference for acetate over glucose. CONCLUSION: We demonstrated the feasibility of deuterium MRSI for noninvasive imaging and assessment of myocardial energy metabolism in vivo. Although the strong signal and large dynamics of myocardial deuterated water may provide a sensitive imaging biomarker, quantifying the metabolic rates still poses a challenge due to the confounding effects of blood recirculation, perfusion, and multiple deuterated water production pathways. In contrast, the deuterated glutamate/glutamine signal and change should directly reflect the metabolic activity of the myocardial tricarboxylic acid cycle, which can be used to study the metabolic shift in substance preference between acetate and glucose in the diseased state. Deuterium MRSI is noninvasive and robust and may have the potential to assess myocardial energy metabolism in human patients.

7.
Dalton Trans ; 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34231597

RESUMO

The strict tolerance space of three-dimensional (3D) crystalline structures is still a significant challenge in the area of switching dielectrics in comparison with lower-dimensional structures. Generally, the function of crystalline materials can be given or adjusted by controlling the environment in which synthesis takes place or the packing rearrangement. Using this method, special functional enhancements or changes in the dielectrics can be realized by improving the synthetic strategies. Here, a 3D switchable dielectric compound [MeHdabco]K(BF4)3 was achieved by employing the temperature selective effect. In particular, its structure is completely different from the usual 3D perovskite structure, which is constructed using two different cation-template frameworks. Moreover, the 3D [MeHdabco]K(BF4)3 shows a structural phase transition at 358 K. The thermal analysis (differential scanning calorimetry (DSC)) and X-ray diffractometry results provided evidence of these phase changes. This work provides a feasible strategy that can be used to achieve the different structures of an 'isomer', and enrich the method used for designing diverse functional materials.

8.
Artigo em Inglês | MEDLINE | ID: mdl-34235934

RESUMO

Metal organic frameworks (MOFs) have been widely researched and applied in many fields. However, the poor electrical conductivity of many traditional MOFs greatly limits their application in electrochemistry, especially in energy storage. Benefited from the full charge delocalization in the atomical plane, conductive MOFs (c-MOFs) exhibit good electrochemical performance. Besides, unlike graphene, c-MOFs are provided with 1D cylindrical channels, which can facilitate the ion transport and enable high ion conductivity. Transition-metal oxides (TMOs) are promising materials with good electrochemical energy storage performance due to their excellent oxidation-reduction activity. When composited with TMOs, the c-MOFs can significantly improve the capacitance and rate performance. In this work, for the first time, we designed serial MnO2@Ni-HHTP (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) nanoarrays with different lengths and explored how the lengths influence the electrochemical energy storage performance. By taking advantage of the high redox activity of MnO2 and the excellent electron and ion conductivity in Ni-HHTP, when assembled as the positive electrode material in an aqueous asymmetric supercapacitor, the device displays high energy density, outstanding rate performance, and superior cycle stability. We believe that the results of this work would provide a good prospect for developing other c-MOF composites as a potential class of electrode materials in energy storage and conversion.

9.
Adv Sci (Weinh) ; : e2100964, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34258884

RESUMO

Stem cell senescence contributes to stem cell exhaustion and drives various aging-associated disorders. However, strategies to rejuvenate senescent stem cells are limited. The present study proposes an approach based on triboelectric stimulation to rejuvenate senescent bone marrow mesenchymal stromal cells (BMSCs) by fabricating a pulsed triboelectric nanogenerator (P-TENG) that can produce stable pulsed current output unaffected by the triggered frequency. The senescence phenotypes of aged BMSCs are reversed by triboelectric stimulation at 30 µA at 1.5 Hz. Triboelectric stimulation enhances the proliferation of aged BMSCs and increases their pluripotency and differentiation capacity. Additionally, mechanistic investigations reveal that pulsed triboelectric stimulation by P-TENG rejuvenates senescent BMSCs by enhancing MDM2-dependent p53 degradation, which is demonstrated by loss-of-function studies of MDM2 and p53. Overall, this study identifies a new approach for the rejuvenation of senescent BMSCs and describes a promising therapeutic intervention for many diseases associated with aged BMSCs.

10.
Zhongguo Zhen Jiu ; 41(7): 799-804, 2021 Jul 12.
Artigo em Chinês | MEDLINE | ID: mdl-34259416

RESUMO

The survey is conducted prior to the development of international standard, Guideline for Clinical Practice of Acupuncture-Moxibustion: Migraine (Guideline) to determine the international demand. The survey includes 5 aspects, i.e. the application status of acupuncture and moxibustion abroad and the demand for the development of international standards, the priority of diseases developed by international standards, the necessity of the transformation of international standards from domestic standards, the key clinical problems to be solved by international standards, and the correlation between professional level and demand intention. The survey results show that the international demand of the Guideline is definite. Regarding the application range of acupuncture-moxibustion and the key clinical questions, the special consideration should be taken to the differences in the demands of the practitioners from different countries during the development of standard.

11.
Plant Mol Biol ; 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34260001

RESUMO

KEY MESSAGE: Our results provide insights into heat response mechanisms among Clematis species. Overexpressing CvHSFA2 enhanced the heat resistance of yeast and silencing NbHSFA2 reduced the heat resistance of tobacco. Clematis species are commonly grown in western and Japanese gardens. Heat stress can inhibit many physiological processes mediating plant growth and development. The mechanism regulating responses to heat has been well characterized in Arabidopsis thaliana and some crops, but not in horticultural plants, including Clematis species. In this study, we found that Clematis alpina 'Stolwijk Gold' was heat-sensitive whereas Clematis vitalba and Clematis viticella 'Polish Spirit' were heat-tolerant based on the physiological analyses in heat stress. Transcriptomic profiling identified a set of heat tolerance-related genes (HTGs). Consistent with the observed phenotype in heat stress, 41.43% of the differentially expressed HTGs between heat treatment and control were down-regulated in heat-sensitive cultivar Stolwijk Gold, but only 9.80% and 20.79% of the differentially expressed HTGs in heat resistant C. vitalba and Polish Spirit, respectively. Co-expression network, protein-protein interaction network and phylogenetic analysis revealed that the genes encoding heat shock transcription factors (HSFs) and heat shock proteins (HSPs) may played an essential role in Clematis resistance to heat stress. Two clades of heat-induced CvHSFs were further identified by phylogenetic tree, motif analysis and qRT-PCR. Ultimately, we proposed that overexpressing CvHSFA2-2 could endow yeast with high temperature resistance and silencing its homologous gene NbHSFA2 reduced the heat resistance of tobacco. This study provides first insights into the diversity of the heat response mechanisms among Clematis species.

12.
J Am Chem Soc ; 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34264654

RESUMO

Mid-infrared photothermal microscopy is a new chemical imaging technology in which a visible beam senses the photothermal effect induced by a pulsed infrared laser. This technology provides infrared spectroscopic information at submicrometer spatial resolution and enables infrared spectroscopy and imaging of living cells and organisms. Yet, current mid-infrared photothermal imaging sensitivity suffers from a weak dependence of scattering on the temperature, and the image quality is vulnerable to the speckles caused by scattering. Here, we present a novel version of mid-infrared photothermal microscopy in which thermosensitive fluorescent probes are harnessed to sense the mid-infrared photothermal effect. The fluorescence intensity can be modulated at the level of 1% per Kelvin, which is 100 times larger than the modulation of scattering intensity. In addition, fluorescence emission is free of interference, thus much improving the image quality. Moreover, fluorophores can target specific organelles or biomolecules, thus augmenting the specificity of photothermal imaging. Spectral fidelity is confirmed through fingerprinting a single bacterium. Finally, the photobleaching issue is successfully addressed through the development of a wide-field fluorescence-detected mid-infrared photothermal microscope which allows video rate bond-selective imaging of biological specimens.

13.
Neurourol Urodyn ; 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34252243

RESUMO

AIMS: To investigate the clinical characteristics of health care-seeking men presenting with lower urinary tract symptoms (LUTS) in China and to reveal risk factors for symptom severity. METHODS: This multicenter, hospital-based, cross-sectional study recruited 1477 eligible male subjects, who were at least 45 years, seeking health care at 9 participating hospitals across the mainland China. The general medical information and subjective symptoms were recorded, followed by the measurement of prostate volume, urodynamic indices, and laboratory tests for kidney function, plus glucose/lipid metabolism. Univariate and multivariate linear regression were employed for the detection of risk factors for symptom severity. RESULTS: The proportion of mild, moderate, and severe LUTS was 14.6%, 32.6%, and 52.8%, respectively, with 62.2% reporting the triple combination of storage, voiding, and postmicturition symptoms. Median prostate volume was 44.6 ml, and 71.1% were experiencing comorbidities. Thirteen independent risk factors for LUTS severity were identified, namely, nocturnal voiding episodes and the presence of straining and weak steam; the triple combination of symptom subtypes; general and nocturia quality of life; Qmax and bladder outlet obstruction index; and numbers of comorbidities, hypertension, estimated glomerular filtration rate, and cholesterol and glycosylated hemoglobin. CONCLUSIONS: The majority of health care-seeking LUTS men present with moderate-to-severe and overlapping symptoms, with a high prevalence of both lower urinary tract dysfunction and systemic comorbidities. The evidence from both urological and nonurological independent risk factors demonstrate the multifactorial nature of LUTS, for which a multidisciplinary management is essential.

14.
Pharmacol Res ; 171: 105761, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34242798

RESUMO

Major depressive disorder (MDD) is severely prevalent, and conventional monoaminergic antidepressants gradually exhibit low therapeutic efficiency, especially for patients with treatment-resistant depression. A neuroplasticity hypothesis is an emerging advancement in the mechanism of depression, mainly expressed in the glutamate system, e.g., glutamate receptors and signaling. Dysfunctional glutamatergic neurotransmission is currently considered to be closely associated with the pathophysiology of MDD. Biological function, pharmacological action, and signal attributes in the glutamate system both regulate the neural process. Specific functional subunits could be therapeutic targets to explore the novel glutamatergic modulators, which have fast-acting, and relatively sustained antidepressant effects. Here, the present review summarizes the pathophysiology of MDD found in the glutamate system, exploring the role of glutamate receptors and their downstream effects. These convergent mechanisms have prompted the development of other modulators targeting on glutamate system, including N-methyl-d-aspartate receptor antagonists, selective GluN2B-specific antagonists, glycine binding site agents, and regulators of metabotropic glutamate receptors. Relevant researches underly the putative mechanisms of these drugs, which reverse the damage of depression by regulating glutamatergic neurotransmission. It also provides further insight into the mechanism of depression and exploring potential targets for novel agent development.

15.
Clin Biochem ; 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34252448

RESUMO

BACKGROUND: The renal biopsy is an accurate and reliable gold standard for membranous nephropathy (MN) diagnosis. However, it is an invasive procedure involving the risk of hemorrhage or infection. Thus, an alternative approach that can facilitate the effective diagnosis and treatment monitoring of idiopathic membranous nephropathy (IMN) is urgently needed. METHODS: We established a dual-labeled time-resolved fluoroimmunoassay (TRFIA) to simultaneously detect phospholipase A2 receptor (PLA2R)-IgG4 and PLA2R-IgG antibodies. Utilizing this assay, we determined the ratio of autoantibodies in the serum of patients with different kidney diseases and normal controls. RESULTS: The sensitivity of TRFIA for detecting anti-PLA2R-IgG and anti-PLA2R-IgG4 was 0.12 µg/mL and 0.001 µg/mL, respectively. Human IgA did not interfere with the assay. Compared to anti-PLA2R-IgG alone, the positive rate of IMN could be increased from 86.5 % to 91.7 % through the combined use of anti-PLA2R-IgG4 and the PLA2R-IgG4/IgG ratio. In contrast, the false-positive rates for the detection of IgA nephropathy, lupus nephropathy, diabetic nephropathy, and minimal change nephropathy decreased from 25 to 50 % to 0 %. CONCLUSIONS: The dual-labeled PLA2R-IgG4/IgG-TRFIA for simultaneous detection of anti-PLA2R-IgG4 and anti-PLA2R-IgG will contribute to improved accuracy of IMN diagnosis.

16.
Chem Asian J ; 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34288530

RESUMO

Controllable synthesis of uniformly distributed nanowires of coordination polymers with inherent physical functions is highly desirable but challenging. In particular, the combination of chirality and magnetism into nanowires has potential applications in multifunctional materials and spintronic devices. Herein, we report four pairs of enantiopure coordination polymers with formulae S -, R -Dy(cyampH) 3 ·CH 3 COOH·2H 2 O ( S -1 , R -1 ), S -, R -Dy(cyampH) 3 ·3H 2 O ( S -2 , R -2 ), S -, R -Dy(cyampH) 2 (C 2 H 5 COO)·3H 2 O ( S -3 , R -3 ) and S -, R -Dy(cyampH) 3 ·0.5C 2 H 5 COOH·2H 2 O ( S -4 , R -4 ) [cyampH 2 = S -, R -(1-cyclohexylethyl)aminomethylphosphonic acids], which were obtained depending on the pH of the reaction mixtures and the specific carboxylic acid used as pH regulator. Interestingly, compounds 3 were obtained as superlong nanowires, showing 1D neutral chain structure which contains both phosphonate and propionate anion ligands. While compounds 1 , 2 and 4 appeared as block-like crystals, superhelices and nanorods, respectively, and exhibited similar neutral chain structures containing only phosphonate ligand. Slow magnetization relaxation characteristic of single molecule magnet (SMM) behavior was observed for compounds S -1 and S -3 . Theoretical calculations were performed to rationalize the magneto-structural relationships.

17.
Nat Commun ; 12(1): 4130, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34226546

RESUMO

Chromosomal translocations of the AF10 (or MLLT10) gene are frequently found in acute leukemias. Here, we show that the PZP domain of AF10 (AF10PZP), which is consistently impaired or deleted in leukemogenic AF10 translocations, plays a critical role in blocking malignant transformation. Incorporation of functional AF10PZP into the leukemogenic CALM-AF10 fusion prevents the transforming activity of the fusion in bone marrow-derived hematopoietic stem and progenitor cells in vitro and in vivo and abrogates CALM-AF10-mediated leukemogenesis in vivo. Crystallographic, biochemical and mutagenesis studies reveal that AF10PZP binds to the nucleosome core particle through multivalent contacts with the histone H3 tail and DNA and associates with chromatin in cells, colocalizing with active methylation marks and discriminating against the repressive H3K27me3 mark. AF10PZP promotes nuclear localization of CALM-AF10 and is required for association with chromatin. Our data indicate that the disruption of AF10PZP function in the CALM-AF10 fusion directly leads to transformation, whereas the inclusion of AF10PZP downregulates Hoxa genes and reverses cellular transformation. Our findings highlight the molecular mechanism by which AF10 targets chromatin and suggest a model for the AF10PZP-dependent CALM-AF10-mediated leukemogenesis.

18.
Science ; 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34210892

RESUMO

The emergence of highly transmissible SARS-CoV-2 variants of concern (VOC) that are resistant to therapeutic antibodies highlights the need for continuing discovery of broadly reactive antibodies. We identify four receptor-binding domain targeting antibodies from three early-outbreak convalescent donors with potent neutralizing activity against 23 variants including the B.1.1.7, B.1.351, P.1, B.1.429, B.1.526 and B.1.617 VOCs. Two antibodies are ultrapotent, with sub-nanomolar neutralization titers (IC50 0.3 to 11.1 ng/mL; IC80 1.5 to 34.5 ng/mL). We define the structural and functional determinants of binding for all four VOC-targeting antibodies and show that combinations of two antibodies decrease the in vitro generation of escape mutants, suggesting their potential in mitigating resistance development.

19.
Trials ; 22(1): 437, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34238342

RESUMO

BACKGROUND: Extensive-stage small-cell lung cancer (ES-SCLC) is characterized by extensive metastases, aggressive progression, and poor prognosis. Chemotherapy is applied as a preferred first-line regimen for ES-SCLC, but inadequate for improving its overall survival. Traditional Chinese medicine (TCM) is widely used in the clinical practice of ES-SCLC for its synergy with chemotherapy. However, there is still no substantial evidence to prove that TCM can effectively improve the long-term efficacy of ES-SCLC patients. The study intends to determine whether the TCM with chemotherapy can improve the overall survival (OS) in treating with ES-SCLC when compared with chemotherapy alone. METHOD/DESIGN: A multicenter, randomized, single-blind, placebo-controlled clinical trial will be conducted to determine whether the TCM granules combined with chemotherapy can improve the OS of ES-SCLC. Two hundred seventy participants will randomly receive 4-6 cycles (21 days per cycle) of chemotherapy plus TCM granules or placebo. The primary outcome measure is OS. The secondary outcome measures includes progression-free survival (PFS), objective response rate (ORR), quality of life (QoL), and tumor markers. Visits will be performed at the end of each cycle during the treatment period and then every 3 months in the follow-up period until the patients' death or study completion. DISCUSSION: The study's result will provide a high-level evidence for TCM granules using with chemotherapy on the first-line treatment of ES-SCLC. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR1900022991 . Registered on 6 May 2019 (prospective registration).


Assuntos
Neoplasias Pulmonares , Medicina Tradicional Chinesa , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Método Duplo-Cego , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Estudos Multicêntricos como Assunto , Estudos Prospectivos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Método Simples-Cego
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