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1.
Nano Lett ; 24(15): 4625-4632, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38568748

RESUMO

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.
Phys Rev Lett ; 132(11): 114001, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38563918

RESUMO

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.

3.
Nat Chem Biol ; 18(11): 1196-1203, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35982227

RESUMO

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.


Assuntos
Receptores Acoplados a Proteínas G , Transdução de Sinais , Humanos , Masculino , Microscopia Crioeletrônica , Sulfato de Desidroepiandrosterona , Desoxicorticosterona , Ligantes , Receptores Acoplados a Proteínas G/química
4.
Artigo em Inglês | MEDLINE | ID: mdl-38758145

RESUMO

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.

5.
Ecotoxicol Environ Saf ; 272: 116105, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38364760

RESUMO

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.


Assuntos
Citoesqueleto , Oogênese , Humanos , Animais , Camundongos , Citoesqueleto/metabolismo , Oócitos/metabolismo , Mitocôndrias/metabolismo , Microtúbulos/metabolismo , Mamíferos
6.
Reproduction ; 166(6): 473-484, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37732584

RESUMO

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.


Assuntos
Senescência Celular , Mitocôndrias , Oócitos , Animais , Feminino , Camundongos , Gravidez , Mitocôndrias/metabolismo , Oócitos/metabolismo , RNA , RNA Mensageiro/metabolismo
7.
Ecotoxicol Environ Saf ; 252: 114612, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36774798

RESUMO

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.


Assuntos
Desinfecção , Desenvolvimento Embrionário , Gravidez , Feminino , Camundongos , Animais , Diferenciação Celular , Mamíferos
8.
BMC Cardiovasc Disord ; 22(1): 48, 2022 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-35152887

RESUMO

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.


Assuntos
Oxigenação por Membrana Extracorpórea/mortalidade , Coração Artificial , Balão Intra-Aórtico/mortalidade , Choque Cardiogênico/mortalidade , Choque Cardiogênico/terapia , Oxigenação por Membrana Extracorpórea/efeitos adversos , Coração Auxiliar , Mortalidade Hospitalar , Humanos , Balão Intra-Aórtico/efeitos adversos , Metanálise em Rede , Estudos Observacionais como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Fatores de Risco , Choque Cardiogênico/diagnóstico , Choque Cardiogênico/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
9.
J Assist Reprod Genet ; 39(11): 2669-2676, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36094700

RESUMO

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.


Assuntos
Ácido Hialurônico , Zona Pelúcida , Feminino , Humanos , Gravidez , Camundongos , Animais , Ácido Hialurônico/farmacologia , Blastocisto , Blastômeros , Embrião de Mamíferos
10.
J Cell Mol Med ; 25(6): 2931-2943, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33523568

RESUMO

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.


Assuntos
Adenosina Quinase/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Animais , Apoptose/efeitos dos fármacos , Biomarcadores , Gerenciamento Clínico , Modelos Animais de Doenças , Suscetibilidade a Doenças , Camundongos , Mitocôndrias/efeitos dos fármacos , Morfolinas/farmacologia , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/etiologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Necroptose/efeitos dos fármacos , Pirimidinas/farmacologia , Ratos , Espécies Reativas de Oxigênio/metabolismo
11.
J Org Chem ; 86(5): 4018-4026, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33586977

RESUMO

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.

12.
BMC Infect Dis ; 21(1): 415, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33947336

RESUMO

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.


Assuntos
Imunoglobulinas Intravenosas/uso terapêutico , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Síndrome de Linfonodos Mucocutâneos/etiologia , Transaminases/sangue , Proteína C-Reativa/análise , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/fisiopatologia , Ecocardiografia , Febre/tratamento farmacológico , Febre/etiologia , Humanos , Lactente , Masculino
13.
Nucleic Acids Res ; 47(11): 5670-5683, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-30949703

RESUMO

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.


Assuntos
Proteínas de Ciclo Celular/fisiologia , Prófase Meiótica I , Proteínas Nucleares/fisiologia , Complexo Sinaptonêmico/fisiologia , Animais , Sistemas CRISPR-Cas , Segregação de Cromossomos , Proteínas de Ligação a DNA , Feminino , Células HEK293 , Humanos , Masculino , Meiose , Camundongos , Camundongos Knockout , Proteínas Nucleares/genética , Ligação Proteica , Recombinação Genética , Espermatócitos/metabolismo , Testículo/metabolismo
14.
Biochem Biophys Res Commun ; 504(4): 777-783, 2018 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-30217444

RESUMO

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.


Assuntos
Aldeído-Desidrogenase Mitocondrial/metabolismo , Células Endoteliais/efeitos dos fármacos , Etanol/toxicidade , Sirtuína 1/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Acetilação , Aldeído-Desidrogenase Mitocondrial/genética , Aorta/citologia , Células Cultivadas , Senescência Celular , Relação Dose-Resposta a Droga , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Humanos , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Transporte Proteico/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Sirtuína 1/genética , Testes de Toxicidade Crônica
15.
J Org Chem ; 83(4): 1772-1778, 2018 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-29355324

RESUMO

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.

16.
Appl Opt ; 57(25): 7259-7265, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30182987

RESUMO

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.

17.
Sensors (Basel) ; 18(7)2018 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-29937502

RESUMO

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.

18.
Zhonghua Zhong Liu Za Zhi ; 37(6): 431-5, 2015 Jun.
Artigo em Zh | MEDLINE | ID: mdl-26463146

RESUMO

OBJECTIVE: To investigate the value of the liquid-based cytology (LBC) of brushing specimens obtained via fiberoptic bronchoscopy for clinical diagnosis of lung cancer. METHODS: We retrospectively analyzed the LBC cases in our hospital from January 2011 to May 2012, and evaluate its role in the diagnosis of lung cancer. RESULTS: The clinical data of a total of 4 380 cases were reviewed and 3 763 of them had histopathological or clinical follow-up results (including 3 306 lung cancer cases and 457 benign lesion cases). The sensitivity, specificity, and accuracy of LBC diagnosis for lung cancer were 72.4% (2 392/3 306), 99.3% (454/457) and 75.6% (2 846/3 763), respectively. Of the 1 992 lung cancer cases diagnosed by brushing LBC, 528 cases (26.5%) were failed to take forceps biopsy and 113 cases (5.7%) showed negative forceps biopsy results. The accurate rate of subtyping of LBC for non-small cell carcinoma and small cell carcinoma was 99.0% (1 487/1 502) (P < 0.001). Take the resection histopathology as gold standard, the accurate rates of subtyping squamous cell carcinoma, adenocarcinoma and small cell carcinoma by LBC were 95.6% (351/367), 95.6% (351/367) and 100% (367/367), respectively, (P < 0.001). The accurate rates of subtyping of squamous cell carcinoma, adenocarcinoma and small cell carcinoma by forceps biopsy were 97.0% (293/302), 97.4% (294/302) and 99.7% (301/302), respectively, (Kappa = 0.895, P < 0.001). There was no significant difference in subtyping respectively between forceps biopsy and brushing LBC (P > 0.05). CONCLUSIONS: Fiberoptic bronchoscopic brushing liquid-based cytology can significantly improve the detection rate of lung cancer, and have a high specificity and accurate rate of subtyping. It is an effective tool for the diagnosis and subtyping of lung cancer.


Assuntos
Adenocarcinoma/patologia , Broncoscopia/métodos , Carcinoma de Células Pequenas/patologia , Carcinoma de Células Escamosas/patologia , Neoplasias Pulmonares/patologia , Carcinoma de Pequenas Células do Pulmão/patologia , Biópsia/instrumentação , Biópsia/métodos , Brônquios , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Estudos Retrospectivos , Sensibilidade e Especificidade , Instrumentos Cirúrgicos
19.
Natl Sci Rev ; 11(3): nwad328, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38449877

RESUMO

The reprogramming of parental epigenomes in human early embryos remains elusive. To what extent the characteristics of parental epigenomes are conserved between humans and mice is currently unknown. Here, we mapped parental haploid epigenomes using human parthenogenetic and androgenetic embryos. Human embryos have a larger portion of genome with parentally specific epigenetic states than mouse embryos. The allelic patterns of epigenetic states for orthologous regions are not conserved between humans and mice. Nevertheless, it is conserved that maternal DNA methylation and paternal H3K27me3 are associated with the repression of two alleles in humans and mice. In addition, for DNA-methylation-dependent imprinting, we report 19 novel imprinted genes and their associated germline differentially methylated regions. Unlike in mice, H3K27me3-dependent imprinting is not observed in human early embryos. Collectively, allele-specific epigenomic reprogramming is different in humans and mice.

20.
Biol Reprod ; 88(6): 160, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23677981

RESUMO

Inhibiting oocyte spontaneous activation (SA) is essential for successful rat cloning by nuclear transfer (NT). This study tested the hypothesis that activities of the Na(+)/Ca(2+) exchanger (NCX) would decrease with oocyte aging and that SA of rat oocytes could be inhibited if the intraoocyte Ca(2+) rises were prevented by activating the NCX through increasing Na(+) concentrations in the culture medium. Elevating Na(+) levels in culture medium by supplementing NaCl inhibited SA of rat oocytes, while maintaining a constant level of maturation-promoting factor and mitogen-activated protein kinase activities. Experiments using the NCX inhibitor bepridil, the Na(+)/K(+)-ATPase inhibitor ouabain, and an assay for intraoocyte Ca(2+) concentrations showed that extracellular Na(+) inhibited rat oocyte SA by enhancing NCX activity and preventing intracellular Ca(2+) rises. Immunohistochemical quantification indicated that the density of NCX1 decreased significantly in aged oocytes that were prone to SA compared with that in freshly ovulated oocytes whose SA rates were low during in vitro culture. Cumulus cell NT showed that sham enucleation caused marked SA in freshly ovulated rat oocytes and that Na(+) supplementation prevented the manipulation-induced SA and improved the in vitro and in vivo development of rat somatic cell NT embryos. Taken together, the results have confirmed our hypothesis that the NCX is active in rat oocytes and its activity decreases with oocyte aging and that activating the NCX by increasing extracellular Na(+) inhibits SA of rat oocytes and improves the development of rat somatic cell NT embryos. These data are also important for understanding the mechanisms of oocyte aging.


Assuntos
Cálcio/metabolismo , Técnicas de Transferência Nuclear , Oócitos/metabolismo , Trocador de Sódio e Cálcio/metabolismo , Animais , Bepridil/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Células do Cúmulo/efeitos dos fármacos , Células do Cúmulo/metabolismo , Transferência Embrionária , Inibidores Enzimáticos/farmacologia , Feminino , Oócitos/efeitos dos fármacos , Ouabaína/farmacologia , Ratos , Ratos Sprague-Dawley , Trocador de Sódio e Cálcio/genética
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