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1.
Br J Haematol ; 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34787307

RESUMO

Natural killer (NK) cells exert anti-viral effects after haematopoietic stem cell transplantation (HSCT). The balance between inhibition and activation of NK cells determined by the inherited repertoire of killer cell immunoglobulin-like receptors (KIR) genes may influence Epstein-Barr virus (EBV) reactivation after transplantation. To evaluate the relative contributions of KIR genotypes to EBV reactivation, we prospectively enrolled 300 patients with malignant haematological disease who were suitable for haploidentical HSCT. Univariate analysis showed that donors with KIR2DS1, KIR2DS3 or KIR3DS1 genes were associated with an increased risk of EBV reactivation [hazard ratio (HR) 1·86, 95% confidence interval (CI) 1·19-2·9, P = 0·0067; HR 1·78, 95% CI 1·07-2·97, P = 0·027; HR 1·86, 95% CI 1·19-2·91, P = 0·0065 respectively]. Multivariate analysis revealed that the presence of KIR2DS1, KIR2DS3 or KIR3DS1 genes was associated with increased EBV reactivation after HSCT. This effect was more evident in the absence of the cognate ligands for the corresponding activating receptors. Our present data firstly showed that donors with activating KIR genes, specifically activating KIR2DS1, KIR2DS3 and KIR3DS1, had an increased risk of EBV reactivation. Precaution for patients whose donors carry activating genes will help prevent EBV reactivation and improve patient prognosis after HSCT.

2.
Artigo em Inglês | MEDLINE | ID: mdl-34796652

RESUMO

BACKGROUND: The pandemic of COVID-19 has a persistent impact on global health, yet its sequelae need to be addressed at a wide scale around the globe. This study aims to investigate the characteristics, prevalence, and risk factors for mid-term (>6 months) clinical sequelae in a cohort of COVID-19 survivors. METHODS: Totally 715 COVID-19 survivors discharged before April 1, 2020, from three medical centers in Wuhan, China, were included. The longitudinal study was conducted by telephone interviews based on a questionnaire including the clinical sequelae of general, respiratory, and cardiovascular systems. Demographics and some characteristics of clinical sequelae of the survivors were recorded and analyzed. Multivariate logistic regression analysis was applied to explore the risk factors for the sequelae. RESULTS: The median time interval from discharge to telephone interview was 225.0 days. The COVID-19 survivors' median ages were 69 years, and 51.3% were male. Among them, 29.9% had at least one clinical sequela. There were 19.2%, 22.7%, and 5.0% of the survivors reporting fatigue, respiratory symptoms, and cardiovascular symptoms, respectively. Comorbidities, disease severity, the application of mechanical ventilation and high-flow oxygen therapy, and the history of re-admission were associated with the presence of clinical sequelae. CONCLUSIONS: Our study provides further evidence for the prevalence and characteristics of clinical sequelae of COVID-19 survivors, suggesting long-term monitoring and management is needed for their full recovery.

3.
Front Chem ; 9: 744977, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660536

RESUMO

With a direct bandgap, two-dimensional (2D) ZnSe is a promising semiconductor material in photoelectric device fields. In this work, based on first-principles methods, we theoretically studied the modulation of the Schottky barrier height (SBH) by applying horizontal and vertical strains on graphene/ZnSe heterojunction. The results show that the inherent electronic properties of graphene and ZnSe monolayers are both well-conserved because of the weak van der Waals (vdW) forces between two sublayers. Under horizontal strain condition, the n(p)-type SBH decreases from 0.56 (1.62) eV to 0.21 (0.78) eV. By changing the interlayer distance in the range of 2.8 Å to 4.4 Å, the n(p)-type SBH decreases (increases) from 0.88 (0.98) eV to 0.21 (1.76) eV. These findings prove the SBH of the heterojunction to be tuned effectively, which is of great significance to optoelectronic devices, especially in graphene/ZnSe-based nano-electronic and optoelectronic devices.

4.
J Am Heart Assoc ; 10(21): e022542, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34713714

RESUMO

Background The gut-derived hormone GLP-1 (glucagon-like peptide-1) exerts beneficial effects against established risk factors for chronic kidney disease. GLP-1 influences renal function by stimulating diuresis and natriuresis and thus lowering arterial blood pressure. The role of the sympathetic nervous system has been implicated as an important link between obesity with elevated arterial pressure and chronic kidney disease. The primary aim of this study was to determine the contribution of renal sympathetic nerves on intrapelvic GLP-1-mediated diuresis and natriuresis in high-fat diet (HFD)-induced obese rats. Methods and Results Obesity was induced in rats by HFD for 12 weeks, followed by either surgical bilateral renal denervation or chronic subcutaneous endopeptidase neprilysin inhibition by sacubitril for a week. Diuretic and natriuretic responses to intrapelvic administration of the GLP-1R (GLP-1 receptor) agonist exendin-4 were monitored in anesthetized control and HFD rats. Renal GLP-1R expression and neprilysin expression and activity were measured. The effects of norepinephrine on the expression of GLP-1R and neprilysin in kidney epithelial LLC-PK1 cells were also examined. We found that diuretic and natriuretic responses to exendin-4 were significantly reduced in the HFD obese rats compared with the control rats (cumulative urine flow at 40 minutes, 387±32 versus 650±65 µL/gkw; cumulative sodium excretion at 40 minutes, 42±5 versus 75±10 µEq/gkw, P<0.05). These responses in the HFD rats were restored after ablation of renal nerves (cumulative urine flow at 40 minutes, 625±62 versus 387±32 µL/gkw; cumulative sodium excretion at 40 minutes, 70±9 versus 42±5 µEq/gkw, P<0.05). Renal denervation induced significant reductions in arterial pressure and heart rate responses to intrapelvic GLP-1 in the HFD rats. Renal denervation also significantly increased the GLP-1R expression and reduced neprilysin expression and activity in renal tissues from the HFD rats. Chronic subcutaneous neprilysin inhibition by sacubitril increased GLP-1-induced diuretic and natriuretic effects in the HFD rats. Finally, exposure of the renal epithelial cells to norepinephrine in vitro led to downregulation of GLP-1R expression but upregulation of neprilysin expression and activity. Conclusions These results suggest that renal sympathetic nerve activation contributes to the blunted diuretic and natriuretic effects of GLP-1 in HFD obese rats. This study provides significant novel insight into the potential renal nerve-neprilysin-GLP-1 pathway involved in renal dysfunction during obesity that leads to hypertension.

5.
FASEB J ; 35(11): e21993, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34670005

RESUMO

Somatic cell nuclear transfer (SCNT) can reprogram differentiated somatic cells to produce individual animals, thus having advantages in animal breeding and chromatin reprogramming. Interspecies SCNT (iSCNT) provides extreme cases of reprogramming failure that can be used to understand the basic biological mechanism of genome reprogramming. It is important to understand the possible mechanisms for the failure of zygotic genome activation (ZGA) in iSCNT embryos in order to improve the efficiency of SCNT embryos. In the present study, we compared the development of bovine-bovine (B-B), ovine-ovine (O-O) SCNT, and ovine-bovine (O-B) iSCNT embryos and found that a developmental block existed in the 8-cell stage in O-B iSCNT embryos. RNA sequencing and q-PCR analysis revealed that the large ribosomal subunit genes (RPL) or the small ribosomal subunit genes (RPS) were expressed at lower levels in the O-B iSCNT embryos. The nucleolin (C23) gene that regulates the ribosomal subunit generation was transcribed at a lower level during embryonic development in O-B iSCNT embryos. In addition, the nucleolin exhibited a clear circular-ring structure in B-B 8-cell stage embryos, whereas this was shell-like or dot-like in the O-B embryos. Furthermore, overexpression of C23 could increase the blastocyst rate of both SCNT and iSCNT embryos and partly rectify the ring-like nucleolin structure and the expression of ribosomal subunit related genes were upregulation, while knockdown of C23 increased the shell-like nucleolin-structure in B-B cloned embryos and downregulated the expression of ribosomal subunit related genes. These results implied that abnormal C23 and ribosome subunit gene expression would lead to the developmental block of iSCNT embryos and ZGA failure. Overexpression of the C23 gene could partly improve the blastocyst development and facilitate the nucleolin structure in bovine preimplantation SCNT embryos.


Assuntos
Desenvolvimento Embrionário , Fibroblastos/citologia , Técnicas de Transferência Nuclear , Fosfoproteínas/fisiologia , Proteínas de Ligação a RNA/fisiologia , Animais , Bovinos , Células Cultivadas , Embrião de Mamíferos , Oócitos , Ovinos
6.
Theriogenology ; 176: 54-62, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34571398

RESUMO

The efficiency of animal artificial breeding in vitro is still low. Oxidative damage is an important obstacle for in vitro artificial breeding of animals. Melatonin can reduce the degree of oxidative damage to both gametes and embryos caused by the external environment. However, there is still some controversy concerning the effect of melatonin on frozen semen, especially in the processes of freezing semen, IVM, IVF and IVC. Here, the effects of melatonin on the whole processes of sperm cryopreservation, oocyte maturation, and embryonic development were studied. The results demonstrated that melatonin at 10-3 M concentration significantly improved progressive sperm viability, plasma membrane integrity, mitochondrial membrane integrity, and acrosome integrity; however, there were also individual differences between bulls, depending on the age of different individuals. The 10-3 M melatonin treatment reduced the reactive oxygen species (ROS) level by nearly 50% in sperm during IVF. Meanwhile, during IVM, the addition of 10-7 M melatonin significantly increased the maturation rate of oocytes and reduced the ROS levels by 58.8%. In addition, 10-7 M melatonin improved the total cell numbers of the IVF blastocysts. Notably, treatment of IVF embryos with melatonin significantly reduced the levels of ROS and influenced the expression levels of key regulatory genes associated with embryo genome activation. This study is of significance for understanding the function of melatonin in animal artificial breeding.


Assuntos
Melatonina , Preservação do Sêmen , Animais , Bovinos , Criopreservação/veterinária , Embrião de Mamíferos , Feminino , Expressão Gênica , Masculino , Melatonina/farmacologia , Gravidez , Sêmen , Preservação do Sêmen/veterinária , Espermatozoides
7.
Mol Neurodegener ; 16(1): 48, 2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34281568

RESUMO

BACKGROUND: Understanding the long-term effects of coronavirus disease 2019 (COVID-19) on cognitive function is essential for monitoring the cognitive decline in the elderly population. This study aims to assess the current cognitive status and the longitudinal cognitive decline in elderly patients recovered from COVID-19. METHODS: This cross-sectional study recruited 1539 COVID-19 inpatients aged over 60 years who were discharged from three COVID-19-designated hospitals in Wuhan, China, from February 10 to April 10, 2020. In total, 466 uninfected spouses of COVID-19 patients were selected as controls. The current cognitive status was assessed using a Chinese version of the Telephone Interview of Cognitive Status-40 (TICS-40) and the longitudinal cognitive decline was assessed using an Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). Cognitive assessments were performed 6 months after patient discharge. RESULTS: Compared with controls, COVID-19 patients had lower TICS-40 scores and higher IQCODE scores [TICS-40 median (IQR): 29 (25 to 32) vs. 30 (26 to 33), p < 0.001; IQCODE median (IQR): 3.19 (3.00 to 3.63) vs. 3.06 (3.00 to 3.38), p < 0.001]. Severe COVID-19 patients had lower TICS-40 scores and higher IQCODE scores than non-severe COVID-19 patients [TICS-40 median (IQR): 24 (18 to 28) vs. 30 (26 to 33), p < 0.001; IQCODE median (IQR): 3.63 (3.13 to 4.31) vs. 3.13 (3.00 to 3.56), p < 0.001] and controls [TICS-40 median (IQR): 24 (18 to 28) vs. 30 (26 to 33), p < 0.001; IQCODE median (IQR) 3.63 (3.13 to 4.31) vs. 3.06 (3.00 to 3.38), p < 0.001]. Severe COVID-19 patients had a higher proportion of cases with current cognitive impairment and longitudinal cognitive decline than non-severe COVID-19 patients [dementia: 25 (10.50 %) vs. 9 (0.69 %), p < 0.001; Mild cognitive impairment (MCI): 60 (25.21 %) vs. 63 (4.84 %), p < 0.001] and controls [dementia: 25 (10.50 %) vs. 0 (0 %), p < 0.001; MCI: 60 (25.21 %) vs. 20 (4.29 %), p < 0.001)]. COVID-19 severity, delirium and COPD were risk factors of current cognitive impairment. Low education level, severe COVID-19, delirium, hypertension and COPD were risk factors of longitudinal cognitive decline. CONCLUSIONS: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with an increased risk of long-term cognitive decline in elderly population. COVID-19 patients, especially severe patients, should be intensively monitored for post-infection cognitive decline.


Assuntos
COVID-19/complicações , Disfunção Cognitiva/virologia , Idoso , Idoso de 80 Anos ou mais , COVID-19/epidemiologia , China , Disfunção Cognitiva/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2
8.
Sensors (Basel) ; 21(14)2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34300391

RESUMO

To meet the high-accuracy position/force control requirements of dual-arm robots for handling a target object, a control algorithm for dual-arm robots based on the modified sliding mode impedance controller MSMIC(tanh) is proposed. First, the combinative kinematics equation of the dual-arm robots and the unified dynamics model combining the manipulated object is established. Second, according to the impedance control motion model for the object, the desired joint angular accelerations of the manipulators are obtained, and the sliding mode controller based on the hyperbolic tangent function as the switch function is introduced to design the coordinated control strategy for dual-arm robots. The stability and convergence of the designed controller are proved according to the Lyapunov function theory. Finally, the operation tasks of the coordinated transport the target object for dual-arm robots are carried out in the simulated experiment environment. Simulation results show that the proposed control scheme can stably output the required internal force and achieve a high-precision trajectory tracking effect while reducing the periodic torque and joint chattering amplitude generated in the conventional sliding mode control algorithm.

9.
Sensors (Basel) ; 21(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209396

RESUMO

Loop Closure Detection (LCD) is an important technique to improve the accuracy of Simultaneous Localization and Mapping (SLAM). In this paper, we propose an LCD algorithm based on binary classification for feature matching between similar images with deep learning, which greatly improves the accuracy of LCD algorithm. Meanwhile, a novel lightweight convolutional neural network (CNN) is proposed and applied to the target detection task of key frames. On this basis, the key frames are binary classified according to their labels. Finally, similar frames are input into the improved lightweight feature matching network based on Transformer to judge whether the current position is loop closure. The experimental results show that, compared with the traditional method, LFM-LCD has higher accuracy and recall rate in the LCD task of indoor SLAM while ensuring the number of parameters and calculation amount. The research in this paper provides a new direction for LCD of robotic SLAM, which will be further improved with the development of deep learning.


Assuntos
Algoritmos , Robótica , Redes Neurais de Computação
10.
J Am Heart Assoc ; 10(14): e020667, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34259031

RESUMO

Background Hypothalamic leptin-mediated signaling contributes to the exaggerated sympatho-excitation and increased blood pressure in obesity-associated hypertension. The aim of the study was to investigate the roles of energy-sensing enzyme sirtuin1 (Sirt1) and forkhead box protein O1 (FoxO1) on the hypothalamic leptin-mediated high sympathetic nerve activity and inflammation in obesity. Methods and Results Sprague Dawley rats were fed with high-fat diet (HFD) for 12 weeks. In vivo, the potential of Srit1 and FoxO1 in the sympathetic effects of leptin was investigated via siRNA injection to knockdown Sirt1 or FoxO1 gene in the arcuate nucleus (ARCN) of hypothalamus in rats. In vitro, the effects of Sirt1 or FoxO1 on leptin-mediated inflammation were observed in proopiomelanocortin (POMC) and microglial cells. Knockdown Sirt1 by siRNA significantly reduced the renal sympathetic nerve activity (RSNA) and blood pressure responses to leptin injection in the ARCN in the HFD rats. Conversely, knockdown FoxO1 significantly enhanced the RSNA and blood pressure responses to leptin injection in the HFD rats. Knockdown Sirt1 reduced the levels of pro-inflammatory cytokines interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), interleukin 1ß (IL-1ß), C1q/TNF-related protein-1 (CTRP1), and immune cell infiltration in the ARCN in the HFD rats. Knockdown FoxO1 significantly increased the level of IL-6 in the ARCN of HFD rats. In cultured hypothalamic POMC and microglial cells, knockdown Sirt1 significantly reduced leptin-induced IL-6 expression, affected the levels of AMP-activated protein kinase (AMPK) and serine/threonine-specific protein kinase (Akt). Knockdown FoxO1 significantly increased leptin-induced IL-6 in both POMC cells and microglial cells. Conclusions These data suggest that both Sirt1 and FoxO1 are the key modulators of leptin signaling in the hypothalamus contributed to the over sympathetic activation and inflammation in obesity.


Assuntos
Metabolismo Energético , Regulação da Expressão Gênica , Hipotálamo/metabolismo , Inflamação/genética , Leptina/metabolismo , Obesidade/genética , Sirtuína 1/genética , Animais , Western Blotting , Células Cultivadas , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Hipotálamo/patologia , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos , Camundongos Knockout , Obesidade/metabolismo , Obesidade/patologia , RNA/genética , Ratos , Ratos Sprague-Dawley , Sirtuína 1/biossíntese
11.
J Cell Physiol ; 236(8): 5921-5936, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33481281

RESUMO

Plant bugs (Miridae species) have become major agricultural pests that cause increasing and severe economic damage. Plant-mediated RNA interference (RNAi) is emerging as an eco-friendly, efficient, and reliable strategy for pest management. In this study, we isolated and characterized a lethal gene of Apolygus lucorum and named it Apolygus lucorum LIM (AlLIM), which produced A. lucorum mortality rates ranging from 38% to 81%. Downregulation of the AlLIM gene expression in A. lucorum by injection of a double-stranded RNA (dsRNA) led to muscle structural disorganization that resulted in metamorphosis deficiency and increased mortality. Then we constructed a plant expression vector that enabled transgenic cotton to highly and stably express dsRNA of AlLIM (dsAlLIM) by Agrobacterium-mediated genetic transformation. In the field bioassay, dsAlLIM transgenic cotton was protected from A. lucorum damage with high efficiency, with almost no detectable yield loss. Therefore, our study successfully provides a promising genetically modified strategy to overpower A. lucorum attack.


Assuntos
Gossypium/parasitologia , Heterópteros/genética , Insetos/genética , Interferência de RNA/imunologia , Animais , Plantas/parasitologia
12.
Brief Bioinform ; 22(3)2021 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32392583

RESUMO

N6-methyladenosine (m6A) is the most abundant posttranscriptional modification in mammalian mRNA molecules and has a crucial function in the regulation of many fundamental biological processes. The m6A modification is a dynamic and reversible process regulated by a series of writers, erasers and readers (WERs). Different WERs might have different functions, and even the same WER might function differently in different conditions, which are mostly due to different downstream genes being targeted by the WERs. Therefore, identification of the targets of WERs is particularly important for elucidating this dynamic modification. However, there is still no public repository to host the known targets of WERs. Therefore, we developed the m6A WER target gene database (m6A2Target) to provide a comprehensive resource of the targets of m6A WERs. M6A2Target provides a user-friendly interface to present WER targets in two different modules: 'Validated Targets', referred to as WER targets identified from low-throughput studies, and 'Potential Targets', including WER targets analyzed from high-throughput studies. Compared to other existing m6A-associated databases, m6A2Target is the first specific resource for m6A WER target genes. M6A2Target is freely accessible at http://m6a2target.canceromics.org.

13.
Hypertension ; 77(1): 147-157, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33296248

RESUMO

Central infusion of Ang II (angiotensin II) has been associated with increased sympathetic outflow resulting in neurogenic hypertension. In the present study, we appraised whether the chronic increase in central Ang II activates the paraventricular nucleus of the hypothalamus (PVN) resulting in elevated sympathetic tone and altered baro- and chemoreflexes. Further, we evaluated the contribution of HIF-1α (hypoxia-inducible factor-1α), a transcription factor involved in enhancing the expression of N-methyl-D-aspartate receptors and thus glutamatergic-mediated sympathetic tone from the PVN. Ang II infusion (20 ng/minute, intracerebroventricular, 14 days) increased mean arterial pressure (126±9 versus 84±4 mm Hg), cardiac sympathetic tone (96±7 versus 75±6 bpm), and decreased cardiac parasympathetic tone (16±2 versus 36±3 versus bpm) compared with saline-infused controls in conscious rats. The Ang II-infused group also showed an impaired baroreflex control of heart rate (-1.50±0.1 versus -2.50±0.3 bpm/mm Hg), potentiation of the chemoreflex pressor response (53±7 versus 30±7 mm Hg) and increased number of FosB-labeled cells (53±3 versus 19±4) in the PVN. Concomitant with the activation of the PVN, there was an increased expression of HIF-1α and N-Methyl-D-Aspartate-type1 receptors in the PVN. Further, Ang II-infusion showed increased renal sympathetic nerve activity (20.5±2.3% versus 6.4±1.9% of Max) and 3-fold enhanced renal sympathetic nerve activity responses to microinjection of N-methyl-D-aspartate (200 pmol) into the PVN of anesthetized rats. Further, silencing of HIF-1α in NG108 cells abrogated the expression of N-methyl-D-aspartate-N-methyl-D-aspartate-type1 induced by Ang II. Taken together, our studies suggest a novel Ang II-HIF-1α-N-methyl-D-aspartate receptor-mediated activation of preautonomic neurons in the PVN, resulting in increased sympathetic outflow and alterations in baro- and chemoreflexes.


Assuntos
Angiotensina II/farmacologia , Ácido Glutâmico/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Sistema Nervoso Simpático/efeitos dos fármacos , Animais , Barorreflexo/efeitos dos fármacos , Barorreflexo/fisiologia , Hipertensão/fisiopatologia , Rim/inervação , Masculino , N-Metilaspartato/farmacologia , Núcleo Hipotalâmico Paraventricular/fisiologia , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/fisiologia , Sistema Nervoso Simpático/fisiologia
14.
Nanomaterials (Basel) ; 10(9)2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32916951

RESUMO

Graphene-based van der Waals (vdW) heterojunction plays an important role in next-generation optoelectronics, nanoelectronics, and spintronics devices. The tunability of the Schottky barrier height (SBH) is beneficial for improving device performance, especially for the contact resistance. Herein, we investigated the electronic structure and interfacial characteristics of the graphene/AlN interface based on density functional theory. The results show that the intrinsic electronic properties of graphene changed slightly after contact. In contrast, the valence band maximum of AlN changed significantly due to the hybridization of Cp and Np orbital electrons. The Bader charge analysis showed that the electrons would transfer from AlN to graphene, implying that graphene would induce acceptor states. Additionally, the Schottky contact nature can be effectively tuned by the external electric field, and it will be tuned from the p-type into n-type once the electric field is larger than about 0.5 V/Å. Furthermore, the optical absorption of graphene/AlN is enhanced after contact. Our findings imply that the SBH is controllable, which is highly desirable in nano-electronic devices.

15.
Phys Chem Chem Phys ; 22(32): 17833-17841, 2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32744552

RESUMO

Recently, as a novel member of the IV-VI group compounds, two-dimensional (2D) buckled monolayer CSe has been discovered for use in high-performance light-emitting devices (Q. Zhang, Y. Feng, X. Chen, W. Zhang, L. Wu and Y. Wang, Nanomaterials, 2019, 9, 598). However, to date, the heat transport properties of this novel CSe is still lacking, which would hinder its potential application in electronic devices and thermoelectric materials that can generate electricity from waste heat. Here we systematically study the heat transport properties of monolayer CSe based on ab initio calculations and phonon Boltzmann transport theory. We find that the lattice thermal conductivity κlat of monolayer CSe is around 42 W m-1 K-1 at room temperature, which is much lower than those of black phosphorene, buckled phosphorene, MoS2, and buckled arsenene. Moreover, the longitudinal acoustic phonon mode contributes the most to the κlat, which is much larger than those of the out-of-plane phonon mode and transverse acoustic branches. The calculated size-dependent κlat shows that the sample size can significantly reduce the κlat of monolayer CSe and can persist up to 10 µm. These discoveries provide new insight into the size-dependent thermal transport in nanomaterials and guide the design of CSe-based low-dimensional quantum devices, such as thermoelectric devices.

17.
EMBO Rep ; 21(9): e50054, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32715614

RESUMO

Cloned animals generated by somatic cell nuclear transfer (SCNT) have been reported for many years; however, SCNT is extremely inefficient, and zygotic genome activation (ZGA) is required for SCNT-mediated somatic cell reprogramming. To identify candidate factors that facilitate ZGA in SCNT-mediated reprogramming, we performed siRNA-repressor and mRNA-inducer screenings, which reveal Dux, Dppa2, and Dppa4 as key factors enhancing ZGA in SCNT. We show that direct injection of ZGA inducers has no significant effect on SCNT blastocyst formation; however, following the establishment of an inducible Dux transgenic mouse model, we demonstrate that transient overexpression of Dux not only improves SCNT efficiency but also increases that of chemically induced pluripotent stem cell reprogramming. Moreover, transcriptome profiling reveals that Dux-treated SCNT embryos are similar to fertilized embryos. Furthermore, transient overexpression of Dux combined with inactivation of DNA methyltransferases (Dnmts) further promotes the full embryonic development of SCNT-derived animals. These findings enhance our understanding of ZGA-regulator function in somatic reprogramming.


Assuntos
Células-Tronco Pluripotentes Induzidas , Animais , Blastocisto , Reprogramação Celular/genética , Embrião de Mamíferos , Desenvolvimento Embrionário/genética , Genoma , Camundongos , Proteínas Nucleares , Técnicas de Transferência Nuclear , Fatores de Transcrição/genética , Zigoto
18.
J Colloid Interface Sci ; 579: 21-27, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32570027

RESUMO

HYPOTHESIS: Hollow nanostructures, known as nanocapsules, have been the preferable candidates in the drug-delivery and control-release applications. To enhance the adherence and penetration into biological hosts for efficient drug delivery, constructing multiple pods on the hollow structure to form a tribulus-like branched architecture has been proven an effective strategy. However, the synthesis is challenging due to the simultaneous control of the branched podal morphology, the hollow architecture and the mesophase structures at the nanometer scale. EXPERIMENTS: Polymer spheres with surface carboxyl moieties were first prepared by emulsion polymerization, which were partly coated by a type of basic silane. The left carboxyl moieties formed some seperated acid spots on the surface of polymer spheres, which could lead to the subsequent self-assembly of surfactant and silica within these acidic spots to grow a branched nanostructure. FINDINGS: Radiolarian-like organic-inorganic hybrid hollow architecture with branched ordered mesoporous pods were obtained after removing the organic templates of the polymer spheres and surfactants by calcination. The ordered cylindrical mesoporous channels were along the central axis direction of the hexagonal-prism-like pods, which connected inside and outside of the hollow spheres. The number of the branched pods could be easily tuned at the range of one to four.

19.
Genomics ; 112(5): 3448-3454, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32569729

RESUMO

Recent studies suggest that a significant proportion of cancers undergo neutral tumor evolution. We applied neutral evolution model in HNSCC patients from The Cancer Genome Atlas (TCGA). To ensure the accuracy of classification results, a sample with the purity of tumor <0.7 was excluded. A tumor sample was considered to evolve neutrally if R2 ≥ 0.98. We found that about 16% of HNSCC patients undergo neutral tumor evolution. We showed that neutral evolution HNSCC patients have better prognosis and higher activities of immune response pathways, and the numbers of co-occurring mutation events and significantly positive selection mutations are significantly less than non-neutral evolution HNSCC patients. In conclusion, we described a comprehensive clinical and genomic characteristics of neutral tumor evolution in Head and Neck Squamous Cell Carcinoma (HNSCC), and provided evidence that the evolution history of HNSCC has both clinical and biological implications.


Assuntos
Neoplasias de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Genômica , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/imunologia , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Mutação , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagem , Carcinoma de Células Escamosas de Cabeça e Pescoço/imunologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade
20.
Cardiovasc Diabetol ; 19(1): 57, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32384887

RESUMO

BACKGROUND: Glucagon-like peptide-1 (GLP-1) induces diuresis and natriuresis. Previously we have shown that GLP-1 activates afferent renal nerve to increase efferent renal sympathetic nerve activity that negates the diuresis and natriuresis as a negative feedback mechanism in normal rats. However, renal effects of GLP-1 in heart failure (HF) has not been elucidated. The present study was designed to assess GLP-1-induced diuresis and natriuresis in rats with HF and its interactions with renal nerve activity. METHODS: HF was induced in rats by coronary artery ligation. The direct recording of afferent renal nerve activity (ARNA) with intrapelvic injection of GLP-1 and total renal sympathetic nerve activity (RSNA) with intravenous infusion of GLP-1 were performed. GLP-1 receptor expression in renal pelvis, densely innervated by afferent renal nerve, was assessed by real-time PCR and western blot analysis. In separate group of rats after coronary artery ligation selective afferent renal denervation (A-RDN) was performed by periaxonal application of capsaicin, then intravenous infusion of GLP-1-induced diuresis and natriuresis were evaluated. RESULTS: In HF, compared to sham-operated control; (1) response of increase in ARNA to intrapelvic injection of GLP-1 was enhanced (3.7 ± 0.4 vs. 2.0 ± 0.4 µV s), (2) GLP-1 receptor expression was increased in renal pelvis, (3) response of increase in RSNA to intravenous infusion of GLP-1 was enhanced (132 ± 30% vs. 70 ± 16% of the baseline level), and (4) diuretic and natriuretic responses to intravenous infusion of GLP-1 were blunted (urine flow 53.4 ± 4.3 vs. 78.6 ± 4.4 µl/min/gkw, sodium excretion 7.4 ± 0.8 vs. 10.9 ± 1.0 µEq/min/gkw). A-RDN induced significant increases in diuretic and natriuretic responses to GLP-1 in HF (urine flow 96.0 ± 1.9 vs. 53.4 ± 4.3 µl/min/gkw, sodium excretion 13.6 ± 1.4 vs. 7.4 ± 0.8 µEq/min/gkw). CONCLUSIONS: The excessive activation of neural circuitry involving afferent and efferent renal nerves suppresses diuretic and natriuretic responses to GLP-1 in HF. These pathophysiological responses to GLP-1 might be involved in the interaction between incretin-based medicines and established HF condition. RDN restores diuretic and natriuretic effects of GLP-1 and thus has potential beneficial therapeutic implication for diabetic HF patients.


Assuntos
Capsaicina/administração & dosagem , Diurese/efeitos dos fármacos , Diuréticos/administração & dosagem , Peptídeo 1 Semelhante ao Glucagon/administração & dosagem , Insuficiência Cardíaca/tratamento farmacológico , Rim/efeitos dos fármacos , Rim/inervação , Natriurese/efeitos dos fármacos , Simpatectomia Química , Animais , Modelos Animais de Doenças , Insuficiência Cardíaca/fisiopatologia , Infusões Intravenosas , Masculino , Ratos Sprague-Dawley
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