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1.
Nano Lett ; 24(15): 4625-4632, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38568748

RESUMEN

Transport probes the motion of quasi-particles in response to external excitations. Apart from the well-known electric and thermoelectric transport, acoustoelectric transport induced by traveling acoustic waves has rarely been explored. Here, by adopting hybrid nanodevices integrated with piezoelectric substrates, we establish a simple design of acoustoelectric transport with gate tunability. We fabricate dual-gated acoustoelectric devices based on hBN-encapsulated graphene on LiNbO3. Longitudinal and transverse acoustoelectric voltages are generated by launching a pulsed surface acoustic wave. The gate dependence of zero-field longitudinal acoustoelectric signal presents strikingly similar profiles to that of Hall resistivity, providing a valid approach for extracting carrier density without magnetic field. In magnetic fields, acoustoelectric quantum oscillations appear due to Landau quantization, which are more robust and pronounced than Shubnikov-de Haas oscillations. Our work demonstrates a feasible acoustoelectric setup with gate tunability, which can be extended to the broad scope of various van der Waals materials.

2.
Nano Lett ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39133825

RESUMEN

Light-to-electricity conversion is crucial for energy harvesting and photodetection, requiring efficient electron-hole pair separation to prevent recombination. Traditional junction-based mechanisms using built-in electric fields fail in nonbarrier regions. Homogeneous material harvesting under a photovoltaic effect is appealing but is only realized in noncentrosymmetric systems via a bulk photovoltaic effect. Here we report the realization of a photovoltaic effect by employing surface acoustic waves (SAWs) to generate zero-bias photocurrent in the conventional layered semiconductor MoSe2. SAWs induce periodic modulation to electronic bands and drag the photoexcited pairs toward the traveling direction. The photocurrent is extracted from a local barrier. The separation of generation and extraction processes suppresses recombination and yields a large nonlocal photoresponse. We distinguish the acousto-electric drag and electron-hole pair separation effect by fabricating devices of different configurations. The acousto-drag photovoltaic effect, enabled by piezoelectric integration, offers an efficient light-to-electricity conversion method, independent of semiconductor crystal symmetry.

3.
Small ; : e2312221, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39007285

RESUMEN

Ultrasound imaging is extensively used in biomedical science and clinical practice. Imaging resolution and tunability of imaging plane are key performance indicators, but both remain challenging to be improved due to the longer wavelength compared with light and the lack of zoom lens for ultrasound. Here, the ultrasound zoom imaging based on a stretchable planar metalens that simultaneously achieves the subwavelength imaging resolution and dynamic control of the imaging plane is reported. The proposed zoom imaging ultrasonography enables precise bone fracture diagnosis and comprehensive osteoporosis assessment. Millimeter-scale microarchitectures of the cortical bones at different depths can be selectively imaged with a 0.6-wavelength resolution. The morphological features of bone fractures, including the shape, size and position, are accurately detected. Based on the extracted ultrasound information of cancellous bones with healthy matrix, osteopenia and osteoporosis, a multi-index osteoporosis evaluation method is developed. Furthermore, it provides additional biological information in aspects of bone elasticity and attenuation to access the comprehensive osteoporosis assessment. The soft metalens also features flexibility and biocompatibility for preferable applications on wearable devices. This work provides a strategy for the development of high-resolution ultrasound biomedical zoom imaging and comprehensive bone quality diagnosis system.

4.
Phys Rev Lett ; 132(11): 114001, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38563918

RESUMEN

The Doppler effect is a universal wave phenomenon that has inspired various applications due to the induced frequency shift. In the case of the linear Doppler effect, the frequency shift depends on the incident frequency and angle. Here, we unveil the frequency shift dependence induced by the acoustic rotational Doppler effect in the wave-object scattering process. We experimentally demonstrate that this frequency shift is exclusively determined by the angular speed and rotational symmetry of the spinning scatterer while remaining independent of the incident angular momentum and angle. We derive the analytical relationship between the frequency shift and the scatterer's helicity, presenting a novel approach for helical feature recognition. The angle-independent nature of the frequency shift inherently prevents spectrum broadening and offers a solution for precise motion measurement through the rotational Doppler effect. This work provides a rigorous and comprehensive understanding of the acoustic Doppler effect, enriching its applications in helicity and motion detection.

5.
Nat Chem Biol ; 18(11): 1196-1203, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35982227

RESUMEN

Adhesion G protein-coupled receptors are elusive in terms of their structural information and ligands. Here, we solved the cryogenic-electron microscopy (cryo-EM) structure of apo-ADGRG2, an essential membrane receptor for maintaining male fertility, in complex with a Gs trimer. Whereas the formations of two kinks were determinants of the active state, identification of a potential ligand-binding pocket in ADGRG2 facilitated the screening and identification of dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate and deoxycorticosterone as potential ligands of ADGRG2. The cryo-EM structures of DHEA-ADGRG2-Gs provided interaction details for DHEA within the seven transmembrane domains of ADGRG2. Collectively, our data provide a structural basis for the activation and signaling of ADGRG2, as well as characterization of steroid hormones as ADGRG2 ligands, which might be used as useful tools for further functional studies of the orphan ADGRG2.


Asunto(s)
Receptores Acoplados a Proteínas G , Transducción de Señal , Humanos , Masculino , Microscopía por Crioelectrón , Sulfato de Deshidroepiandrosterona , Desoxicorticosterona , Ligandos , Receptores Acoplados a Proteínas G/química
6.
Cell Biol Toxicol ; 40(1): 59, 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39060559

RESUMEN

Acute liver injury (ALI) is a common life-threatening condition with a high mortality rate due to liver disease-related death. However, current therapeutic interventions for ALI remain ineffective, and the development of effective novel therapies is urgently needed. Liver samples from patients with drug-induced ALI were collected to detect adenosine kinase (ADK) expression. Male C57BL/6 J mice, hepatocyte-specific ADK knockout (ADKHKO) mice, and their controls (ADKf/f) were exposed to acetaminophen (APAP) and other treatments to investigate the mechanisms of APAP-related ALI. ADK expression was significantly decreased in APAP-injured livers. Hepatocyte-specific ADK deficiency exacerbated APAP-induced ALI, while a gain-of-function approach delivering AAV-ADK, markedly alleviated APAP-induced ALI, as indicated by changes in alanine aminotransferases (ALT) levels, aspartate aminotransferase (AST) levels, neutrophil infiltration and hepatocyte death. This study showed that ADK played a critical role in ALI by activating autophagy through two signaling pathways, the adenosine monophosphate-activated protein kinase (AMPK)-mTOR pathway and the adenosine receptor A1 (ADORA1)-Akt-mTOR pathway. Furthermore, we found that metformin upregulated ADK expression in hepatocytes and protected against APAP-induced ALI. These results demonstrate that ADK is critical in protecting against APAP-induced ALI and that developing therapeutics targeting ADK-adenosine-ADORA1 is a new approach for ALI treatment. Metformin is a potential candidate for preventing ALI by upregulating ADK.


Asunto(s)
Acetaminofén , Adenosina Quinasa , Autofagia , Enfermedad Hepática Inducida por Sustancias y Drogas , Hepatocitos , Transducción de Señal , Animales , Humanos , Masculino , Ratones , Acetaminofén/efectos adversos , Adenosina Quinasa/metabolismo , Adenosina Quinasa/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Autofagia/efectos de los fármacos , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Hepatocitos/metabolismo , Hepatocitos/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo
7.
Artículo en Inglés | MEDLINE | ID: mdl-38758145

RESUMEN

Objective: This study aims to compare the therapeutic efficacy of laparoscopic right-lower quadrant and midline approaches for the treatment of right-sided colon cancer and evaluate the analgesic effect of parecoxib sodium. Methods: Sixty patients with right-sided colon cancer admitted to Hospital of Lin 'an District between January 2019 and November 2022 were selected. They were divided into the study group A (n=30) with a right-lower quadrant approach and the study group B (n=30) with a midline approach. All patients received parecoxib sodium. Surgical time, blood loss, postoperative complications, and other relevant indicators were recorded and compared between the two groups. Additionally, a control group of 60 right-sided colon cancer patients who underwent conventional non-exclusive analgesic laparoscopic surgery during the same period was included to compare the analgesic effects between the study and control groups. Results: The surgical time (RR = 0.608, 95%CI 0.51, 1.53, P = .042), blood loss (RR = 0.798, 95%CI 0.52, 1.02, P < .001), time for bowel function recovery (RR = 0.808, 95%CI 0.50, 1.77, P = .007), and length of hospital stay (RR = 0.766, 95%CI 0.56, 1.72, P =.052) were significantly lower in group A than in group B, while the number of lymph node dissections was higher in group A (RR = 0.803, 95%CI 0.62, 1.52, P = .047). The postoperative levels of tumor-specific growth factor (TSGF) (RR = 0.710, 95%CI 0.50, 1.55, P < .001) and carcinoembryonic antigen (CEA) (RR = 0.803, 95%CI 0.62, 1.52, P < .001) were significantly decreased in both groups A and B, with no significant difference between the groups (P > .05). The incidence of complications in group A was significantly lower than in group B (RR = 0.167, 95%CI 0.17, 0.63, P = .044). The VAS scores of the study group at 2/4/6/8 hours postoperatively were significantly lower than those of the control group (RR = 0.702, 95%CI 0.52, 1.62, P < .001). The SF-36 scores of the study group were significantly higher than those of the control group (RR = 0.753, 95%CI 0.56, 1.82, P < .001). Conclusions: The Laparoscopic right-lower quadrant approach for the treatment of right-sided colon cancer offers advantages such as shorter surgical time and less blood loss. It demonstrates significant clinical efficacy and reduces the incidence of postoperative complications. Parecoxib sodium enhances postoperative analgesic effect, effectively alleviating patient pain, promoting recovery, and improving quality of life. It is worth promoting in clinical practice.

8.
Ecotoxicol Environ Saf ; 272: 116105, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38364760

RESUMEN

2-bromoacetamide (BAcAm) is an emerging class of unregulated disinfection by-products (DBPs), with potent cytogenetic and developmental toxicity in animals. However, whether BAcAm exerts toxic effects on mammalian oocyte quality remains to be elucidate. In this research, we investigated the effect of BAcAm on mouse and human oocyte maturation with an in vitro culture system. Our results revealed that BAcAm exposure hindered the extrusion of the first polar body, disrupted the spindle organization and reduced the competence of embryo development after fertilization in the mouse oocytes. Results of single-cell RNA sequencing (scRNA-seq) showed that 605 differentially expressed genes (DEGs) were identified in the BAcAm exposed mouse oocytes, among which 366 were up-regulated and 239 were down-regulated. Gene Ontology (GO) analysis further revealed that DEGs were mainly enriched in mitochondrial functions, oxidative stress, cytoskeleton, endoplasmic reticulum (ER), Golgi and protein synthesis, DNA damage and apoptosis. We then conducted further tests in these aspects and discovered that BAcAm exposure principally perturbed the function of microtubule and actin cytoskeleton. This finding was confirmed in human oocytes. Overall, our data suggest that BAcAm exposure disturbs the cytoskeleton function, thus impairing oocyte maturation. These data, for the first time, provide a comprehensive view for the toxic effects of BAcAm on oocyte maturation.


Asunto(s)
Citoesqueleto , Oogénesis , Humanos , Animales , Ratones , Citoesqueleto/metabolismo , Oocitos/metabolismo , Mitocondrias/metabolismo , Microtúbulos/metabolismo , Mamíferos
9.
Reproduction ; 166(6): 473-484, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37732584

RESUMEN

In brief: Post-ovulatory aging (POA) results in a decline in oocyte quality and embryonic developmental capacity although the underlying mechanisms remain elusive. This study provides comprehensive mRNA expression profiles of fresh and aging oocytes in mice for the first time. Abstract: POA impairs the quality of mammalian oocytes with harmful effects on the developmental potential of the embryo. This is a major problem for humans since it is associated with low rate of natural fertility, with high rate of spontaneous abortion and low efficiency of in vitro fertilization. However, the molecular mechanisms underlying this process remain unclear and new methods are demanded to control POA. In this study, we performed single-cell RNA-sequencing (scRNA-seq) analysis on fresh and aging MII mouse oocytes and compared their global RNA transcription patterns. Nine hundred and twenty-one differentially expressed genes (DEGs) were identified. Five hundred and sixty-nine genes were downregulated, while 356 were upregulated in the group of aging oocytes. Gene ontology (GO) enrichment analysis demonstrated that a series of DEGs were significantly enriched involving mitochondrial functions, spindle functions and protein metabolism. The results of qPCR and a series of functional tests further confirmed that the disorder of mitochondrial functions, spindle functions and impairment of protein metabolism were actually involved in the progression of POA. In this study, panoramic mRNA expression profiles of fresh and aging oocytes were depicted and fully validated. Our data will provide a useful resource for further research on the regulation of gene expression of POA and suggest potential strategies to delay and reverse POA.


Asunto(s)
Senescencia Celular , Mitocondrias , Oocitos , Animales , Femenino , Ratones , Embarazo , Mitocondrias/metabolismo , Oocitos/metabolismo , ARN , ARN Mensajero/metabolismo
10.
Ecotoxicol Environ Saf ; 252: 114612, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36774798

RESUMEN

2-bromoacetamide (BAcAm), a new class of disinfection by-products (DBPs), is widely detected in drinking water across the world. Reports of the high cytogenetic toxicity of BAcAm have aroused public attention concerning its toxic effects on early embryonic development. In this study, we optimized an in vitro culture (IVC) system for peri- and early post-implantation mouse embryos and used this system to determine the developmental toxicity of BAcAm. We found that exposure to BAcAm caused a reduction in egg cylinder formation rate and abnormal lineage differentiation in a dose-dependent manner. Transcriptomic analysis further revealed that BAcAm exposure at early developmental stages altered the abundance of transcripts related to a variety of biological processes including gene expression, metabolism, cell proliferation, cell death and embryonic development, thus indicating its toxic effects on embryonic development. Thus, we developed a robust tool for studying the toxicology of chemicals at the early stages of embryonic development and demonstrated the developmental toxicity of BAcAm in the early embryonic development of mammals.


Asunto(s)
Desinfección , Desarrollo Embrionario , Embarazo , Femenino , Ratones , Animales , Diferenciación Celular , Mamíferos
11.
BMC Cardiovasc Disord ; 22(1): 48, 2022 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-35152887

RESUMEN

OBJECTIVE: Mechanical circulatory support (MCS) devices are widely used for cardiogenic shock (CS). This network meta-analysis aims to evaluate which MCS strategy offers advantages. METHODS: A systemic search of PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials was performed. Studies included double-blind, randomized controlled, and observational trials, with 30-day follow-ups. Paired independent researchers conducted the screening, data extraction, quality assessment, and consistency and heterogeneity assessment. RESULTS: We included 39 studies (1 report). No significant difference in 30-day mortality was noted between venoarterial extracorporeal membrane oxygenation (VA-ECMO) and VA-ECMO plus Impella, Impella, and medical therapy. According to the surface under the cumulative ranking curve, the optimal ranking of the interventions was surgical venting plus VA-ECMO, medical therapy, VA-ECMO plus Impella, intra-aortic balloon pump (IABP), Impella, Tandem Heart, VA-ECMO, and Impella plus IABP. Regarding in-hospital mortality and 30-day mortality, the forest plot showed low heterogeneity. The results of the node-splitting approach showed that direct and indirect comparisons had a relatively high consistency. CONCLUSIONS: IABP more effectively reduce the incidence of 30-day mortality compared with VA-ECMO and Impella for the treatment of CS.


Asunto(s)
Oxigenación por Membrana Extracorpórea/mortalidad , Corazón Artificial , Contrapulsador Intraaórtico/mortalidad , Choque Cardiogénico/mortalidad , Choque Cardiogénico/terapia , Oxigenación por Membrana Extracorpórea/efectos adversos , Corazón Auxiliar , Mortalidad Hospitalaria , Humanos , Contrapulsador Intraaórtico/efectos adversos , Metaanálisis en Red , Estudios Observacionales como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Medición de Riesgo , Factores de Riesgo , Choque Cardiogénico/diagnóstico , Choque Cardiogénico/fisiopatología , Factores de Tiempo , Resultado del Tratamiento
12.
J Assist Reprod Genet ; 39(11): 2669-2676, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36094700

RESUMEN

PURPOSE: Zona pellucida-free (ZP-free) embryos often fail to achieve good developmental outcomes and are routinely discarded in assisted reproductive laboratories. Existing attempts to rescue ZP-free embryos are not widely used due to operational complexity and high technical requirements. To handle cases with missing ZP, we applied modified sodium hyaluronate gel (MSHG) to embryo culture to determine if it can function as a substitute for human zona pellucida. METHODS: The developmental process and the blastocyst formation rate of embryos were analyzed in both mouse and human. The first clinical application of MSHG was reported, and the pregnancy outcome was continuously followed up. RESULTS: Human and mouse ZP-free embryos cultured with MSHG showed a blastocyst formation rate similar to ZP-intact embryos. MSHG improves blastocysts formation rate by maintaining blastomere spatial arrangement at early stages. Compared to ZP-free embryos, the proportion of tetrahedrally arranged blastomeres at the 4-cell stage increased significantly in embryos cultured with MSHG in humans. A ZP-free blastocyst cultured in MSHG with the highest score was successfully implanted after day 5 transplantation and developed normally. CONCLUSION: These data demonstrate that MSHG can substitute the function of zona pellucida and rescue human ZP-free embryos during assisted reproductive technology.


Asunto(s)
Ácido Hialurónico , Zona Pelúcida , Femenino , Humanos , Embarazo , Ratones , Animales , Ácido Hialurónico/farmacología , Blastocisto , Blastómeros , Embrión de Mamíferos
13.
J Cell Mol Med ; 25(6): 2931-2943, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33523568

RESUMEN

Increased adenosine helps limit infarct size in ischaemia/reperfusion-injured hearts. In cardiomyocytes, 90% of adenosine is catalysed by adenosine kinase (ADK) and ADK inhibition leads to higher concentrations of both intracellular adenosine and extracellular adenosine. However, the role of ADK inhibition in myocardial ischaemia/reperfusion (I/R) injury remains less obvious. We explored the role of ADK inhibition in myocardial I/R injury using mouse left anterior ligation model. To inhibit ADK, the inhibitor ABT-702 was intraperitoneally injected or AAV9 (adeno-associated virus)-ADK-shRNA was introduced via tail vein injection. H9c2 cells were exposed to hypoxia/reoxygenation (H/R) to elucidate the underlying mechanisms. ADK was transiently increased after myocardial I/R injury. Pharmacological or genetic ADK inhibition reduced infarct size, improved cardiac function and prevented cell apoptosis and necroptosis in I/R-injured mouse hearts. In vitro, ADK inhibition also prevented cell apoptosis and cell necroptosis in H/R-treated H9c2 cells. Cleaved caspase-9, cleaved caspase-8, cleaved caspase-3, MLKL and the phosphorylation of MLKL and CaMKII were decreased by ADK inhibition in reperfusion-injured cardiomyocytes. X-linked inhibitor of apoptosis protein (XIAP), which is phosphorylated and stabilized via the adenosine receptors A2B and A1/Akt pathways, should play a central role in the effects of ADK inhibition on cell apoptosis and necroptosis. These data suggest that ADK plays an important role in myocardial I/R injury by regulating cell apoptosis and necroptosis.


Asunto(s)
Adenosina Quinasa/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Daño por Reperfusión Miocárdica/metabolismo , Animales , Apoptosis/efectos de los fármacos , Biomarcadores , Manejo de la Enfermedad , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Ratones , Mitocondrias/efectos de los fármacos , Morfolinas/farmacología , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Daño por Reperfusión Miocárdica/etiología , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Necroptosis/efectos de los fármacos , Pirimidinas/farmacología , Ratas , Especies Reactivas de Oxígeno/metabolismo
14.
J Org Chem ; 86(5): 4018-4026, 2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33586977

RESUMEN

The regiospecific radical reactions of ß-alkyl nitroalkenes with sulfonyl hydrazides depended to a great extent on the choice of a solvent and catalyst. In the presence of dimethylformamide (DMF), ß-alkyl nitroalkenes more likely converted into electron-rich allyl nitro compounds, which reacted with sulfonyl hydrazides to afford allyl sulfones with high regioselectivity. While in acetonitrile (CH3CN), vinyl sulfones were obtained directly via sulfonation of electron-deficient ß-alkyl nitroalkenes. The mechanism investigation revealed that the regioselectivity was controlled by the equilibrium of ß-alkyl nitroalkenes and allyl nitro compounds.

15.
BMC Infect Dis ; 21(1): 415, 2021 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-33947336

RESUMEN

BACKGROUND: Kawasaki disease (KD) is the most common cause of acquired heart disease among children in developed countries, in which the resulting coronary artery (CA) abnormalities cause myocardial ischemia, infarction, and death. Prompt diagnosis was essential, and supplemental information should be used to assist the diagnosis when classical clinical criteria are incomplete. The elevated levels of serum transaminases in most KD patients are mild. Herein, a case of atypical KD child with severely elevated transaminase was reported. CASE PRESENTATION: A child with clinical manifestations of fever, high C-reactive protein (CRP) and severely elevated transaminases was reported. The treatment effect of antibiotic and liver-protecting drugs was not satisfactory. A bilateral diffuse dilation of the CA was detected on echocardiography on day 5 of the illness; thus, atypical KD was diagnosed. Elevated transaminases declined rapidly to normal after the treatment of intravenous immunoglobulin (IVIG). A 1-month follow-up revealed that CA returned to normal, and 2-month, 6-months, and 1-year follow-up revealed the child was in good general health. CONCLUSIONS: This case highlighted that atypical KD clinical symptoms were diverse, and severely elevated transaminases might provide a clue to healthcare providers for the diagnosis and management of atypical KD.


Asunto(s)
Inmunoglobulinas Intravenosas/uso terapéutico , Síndrome Mucocutáneo Linfonodular/tratamiento farmacológico , Síndrome Mucocutáneo Linfonodular/etiología , Transaminasas/sangre , Proteína C-Reactiva/análisis , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/fisiopatología , Ecocardiografía , Fiebre/tratamiento farmacológico , Fiebre/etiología , Humanos , Lactante , Masculino
16.
Nucleic Acids Res ; 47(11): 5670-5683, 2019 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-30949703

RESUMEN

Meiosis is a specialized cell division for producing haploid gametes from diploid germ cells. During meiosis, synaptonemal complex (SC) mediates the alignment of homologs and plays essential roles in homologous recombination and therefore in promoting accurate chromosome segregation. In this study, we have identified a novel protein SCRE (synaptonemal complex reinforcing element) as a key molecule in maintaining the integrity of SC during meiosis prophase I in mice. Deletion of Scre (synaptonemal complex reinforcing element) caused germ cell death in both male and female mice, resulting in infertility. Our mechanistic studies showed that the synapses and SCs in Scre knockout mice were unstable due to the lack of the SC reinforcing function of SCRE, which is sparsely localized as discrete foci along the central elements in normal synaptic homologous chromosomes. The lack of Scre leads to meiosis collapse at the late zygotene stage. We further showed that SCRE interacts with synaptonemal complex protein 1 (SYCP1) and synaptonemal complex central element 3 (SYCE3). We conclude that the function of SCRE is to reinforce the integrity of the central elements, thereby stabilizing the SC and ensuring meiotic cell cycle progression. Our study identified SCRE as a novel SC fastener protein that is distinct from other known SC proteins.


Asunto(s)
Proteínas de Ciclo Celular/fisiología , Profase Meiótica I , Proteínas Nucleares/fisiología , Complejo Sinaptonémico/fisiología , Animales , Sistemas CRISPR-Cas , Segregación Cromosómica , Proteínas de Unión al ADN , Femenino , Células HEK293 , Humanos , Masculino , Meiosis , Ratones , Ratones Noqueados , Proteínas Nucleares/genética , Unión Proteica , Recombinación Genética , Espermatocitos/metabolismo , Testículo/metabolismo
17.
Biochem Biophys Res Commun ; 504(4): 777-783, 2018 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-30217444

RESUMEN

Aldehyde dehydrogenase 2 (ALDH2) plays essential roles in drinking-associated diseases or effects. As we have previously reported, ALDH2 mediates acute ethanol-induced eNOS activation in vitro. However, whether chronic ethanol treatment has a dose-response endothelial protection, as well as the possible mediating role of ALDH2 involved, is unclear. Here, we show that appropriate dose of ethanol preserved the expression and activity of ALDH2 and eNOS, and alleviated senescence-associated phenotypes in human aortic endothelial cells. Furthermore, ALDH2 deficiency impairs the dose-response protection of ethanol against endothelial senescence by promoting the accumulation of 4-HNE, the formation of 4-HNE-SIRT1 protein adducts and the subsequent decrease in SIRT1-dependent p53 deacetylation. Collectively, our data indicate that ALDH2 mediates the protection of appropriate ethanol by modulating SIRT1/p53-dependent endothelial senescence.


Asunto(s)
Aldehído Deshidrogenasa Mitocondrial/metabolismo , Células Endoteliales/efectos de los fármacos , Etanol/toxicidad , Sirtuina 1/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Acetilación , Aldehído Deshidrogenasa Mitocondrial/genética , Aorta/citología , Células Cultivadas , Senescencia Celular , Relación Dosis-Respuesta a Droga , Células Endoteliales/metabolismo , Células Endoteliales/patología , Humanos , Óxido Nítrico Sintasa de Tipo III/genética , Óxido Nítrico Sintasa de Tipo III/metabolismo , Transporte de Proteínas/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Sirtuina 1/genética , Pruebas de Toxicidad Crónica
18.
J Org Chem ; 83(4): 1772-1778, 2018 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-29355324

RESUMEN

A metal-free, open-flask protocol was developed for the preparation of allylic sulfones through direct condensation of sodium arylsulfinates and ß,ß-disubstituted nitroalkenes. The key step of this process was the Lewis base-promoted equilibrium between nitroalkenes and allylic nitro compounds. Through this process, the readily available conjugated nitroalkenes can be easily converted into allylic nitro compounds, which contain more reactive C═C bonds toward the sulfonyl radical addition. As a result, allylic sulfones were prepared in excellent yields with a broad substrate scope under mild conditions.

19.
Appl Opt ; 57(25): 7259-7265, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-30182987

RESUMEN

We propose a novel flame temperature estimation method based on a flame light field sectioned imaging model of complex temperature distribution in different media. The proposed method relies on multi-pixel reconstruction to improve the resolution of sub-aperture images. In addition, the wavelet transform denoises the flame refocused image, and then the Lucy-Richardson algorithm deconvolves the image. The temperature estimation accuracy using the proposed method is higher than that reported in a previous work, with a larger temperature estimation range from 1250 K to 1800 K. Moreover, we found that deconvolution plays an important role in determining the temperature estimation accuracy.

20.
Sensors (Basel) ; 18(7)2018 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-29937502

RESUMEN

A plenoptic cameras is a sensor that records the 4D light-field distribution of target scenes. The surface errors of a microlens array (MLA) can cause the degradation and distortion of the raw image captured by a plenoptic camera, resulting in the confusion or loss of light-field information. To address this issue, we propose a method for the local rectification of distorted images using white light-field images. The method consists of microlens center calibration, geometric rectification, and grayscale rectification. The scope of its application to different sized errors and the rectification accuracy of three basic surface errors, including the overall accuracy and the local accuracy, are analyzed through simulation of imaging experiments. The rectified images have a significant improvement in quality, demonstrating the provision of precise light-field data for reconstruction of real objects.

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