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1.
Plant Cell Physiol ; 65(1): 68-78, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-37814936

RESUMO

Reprograming of chromatin structures and changes in gene expression are critical for plant male gamete development, and epigenetic marks play an important role in these processes. Histone variant H3.3 is abundant in euchromatin and is largely associated with transcriptional activation. The precise function of H3.3 in gamete development remains unclear in plants. Here, we report that H3.3 is abundantly expressed in Arabidopsis anthers and its knockout mutant h3.3-1 is sterile due to male sterility. Transcriptome analysis of young inflorescence has identified 2348 genes downregulated in h3.3-1 mutant, among which 1087 target genes are directly bound by H3.3, especially at their 3' ends. As a group, this set of H3.3 targets is enriched in the reproduction-associated processes including male gamete generation, pollen sperm cell differentiation and pollen tube growth. The function of H3.3 in male gamete development is dependent on the Anti-Silencing Factor 1A/1B (ASF1A/1B)-Histone regulator A (HIRA)-mediated pathway. Our results suggest that ASF1A/1B-HIRA-mediated H3.3 deposition at its direct targets for transcription activation forms the regulatory networks responsible for male gamete development.


Assuntos
Arabidopsis , Histonas , Histonas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Sementes/metabolismo , Fertilidade , Células Germinativas/metabolismo , Cromatina/metabolismo
2.
Am J Transplant ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38615902

RESUMO

The shortage of transplant organs remains a severe global issue. Normothermic machine perfusion (NMP) has the potential to increase organ availability, yet its efficacy is hampered by the inflammatory response during machine perfusion. Mouse liver ischemia-reperfusion injury (IRI) models, discarded human liver models, and porcine marginal liver transplantation models were utilized to investigate whether farnesoid X receptor (FXR) activation could mitigate inflammation-induced liver damage. FXR expression levels before and after reperfusion were measured. Gene editing and coimmunoprecipitation techniques were employed to explore the regulatory mechanism of FXR in inflammation inhibition. The expression of FXR correlates with the extent of liver damage after reperfusion. Activation of FXR significantly suppressed the inflammatory response triggered by IRI, diminished the release of proinflammatory cytokines, and improved liver function recovery during NMP, assisting discarded human livers to reach transplant standards. Mechanistically, FXR disrupts the interaction between p65 and p300, thus inhibiting modulating the nuclear factor kappa-B signaling pathway, a key instigator of inflammation. Our research across multiple species confirms that activating FXR can optimize NMP by attenuating IRI-related liver damage, thereby improving the utilization of marginal livers for transplantation.

3.
Genome Res ; 31(8): 1409-1418, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34244230

RESUMO

R-loops are stable chromatin structures comprising a DNA:RNA hybrid and a displaced single-stranded DNA. R-loops have been implicated in gene expression and chromatin structure, as well as in replication blocks and genome instability. Here, we conducted a genome-wide identification of R-loops and identified more than 700,000 R-loop peaks in the maize (Zea mays) genome. We found that sense R-loops were mainly enriched in promoters and transcription termination sites and relatively less enriched in gene bodies, which is different from the main gene-body localization of sense R-loops in Arabidopsis and Oryza sativa At the chromosome scale, maize R-loops were enriched in pericentromeric heterochromatin regions, and a significant portion of R-loops were derived from transposable elements. In centromeres, R-loops preferentially formed within the binding regions of the centromere-specific histone CENH3, and centromeric retrotransposons were strongly associated with R-loop formation. Furthermore, centromeric retrotransposon R-loops were observed by applying the single-molecule imaging technique of atomic force microscopy. These findings elucidate the fundamental character of R-loops in the maize genome and reveal the potential role of R-loops in centromeres.


Assuntos
Estruturas R-Loop , Zea mays , Centrômero/genética , Mapeamento Cromossômico , Histonas/genética , Histonas/metabolismo , Zea mays/genética , Zea mays/metabolismo
4.
Plant Cell ; 33(11): 3574-3591, 2021 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-34463741

RESUMO

Eukaryotic genomes are transcribed by at least three RNA polymerases, RNAPI, II, and III. Co-transcriptional R-loops play diverse roles in genome regulation and maintenance. However, little is known about how R-loops regulate transcription interference, the transcriptional event that is caused by different RNA polymerases transcribing the same genomic templates. Here, we established that the intragenic transfer RNA (tRNA) genes can promote sense R-loop enrichment (named intra-tR-loops) in Arabidopsis thaliana, and found that intra-tR-loops are decreased in an RNAPIII mutant, NUCLEAR RNA POLYMERASE C, SUBUNIT 7(nrpc7-1). NRPC7 is co-localized with RNAPIIS2P at intragenic tRNA genes and interferes with RNAPIIS2P elongation. Conversely, the binding of NRPC7 at intragenic tRNA genes is increased following inhibition of RNAPII elongation. The transcription of specific tRNA host genes is inhibited by RNAPIII, and the inhibition of tRNA host genes is intra-tR-loop dependent. Moreover, alleviating the inhibition of tRNAPro-induced intra-tR-loops on its host gene AtNUDX1 promotes oxidative stress tolerance in A. thaliana. Our work suggests intra-tR-loops regulate host gene expression by modulating RNA polymerases interference.


Assuntos
Arabidopsis/genética , Estresse Oxidativo/genética , Interferência de RNA , RNA de Plantas/genética , RNA de Transferência/genética , Transcrição Gênica , Arabidopsis/metabolismo
5.
BMC Anesthesiol ; 24(1): 94, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38454342

RESUMO

BACKGROUND: Remimazolam is a novel ultrashort-acting intravenous benzodiazepine sedative-hypnotic. The combination of remimazolam and sevoflurane does not increase respiratory sensitivity, produce bronchospasm, or cause other adverse conditions. We aimed to observe the effects of different remimazolam doses on the minimum alveolar concentration (MAC) of sevoflurane at end-expiration during laryngeal mask insertion and evaluate the effect of sex on the efficacy of the combination of remimazolam on the suppression of laryngeal mask insertion in adult patients. METHODS: We included 240 patients undergoing laparoscopic surgery under general anesthesia with elective placement of a laryngeal mask (120 males and 120 females). The patients were randomly divided into four groups according to sex: a control group (randomization for female patients, RF0; randomization for male patients, RM0) and three remimazolam groups (RF1, RM1 / RM2, RF2 / RM3, RF3), with 30 patients in each group. Induction was established by vital capacity rapid inhalation induction (VCRII), using 8% sevoflurane and 100% oxygen (6 L/min) in all patients. The (RF1, RM1), (RM2, RF2), and (RM3, RF3) groups were continuously injected with remimazolam at doses of 1, 1.5, and 2.0 mg/kg/h, respectively, while the (RM0, RF0) group was injected with an equal volume of normal saline. The end-expiratory concentration of sevoflurane was adjusted to a preset value after the patient's eyelash reflex disappeared. After the end-expiratory concentration of sevoflurane was kept stable for at least 15 min, the laryngeal mask was placed, and the patient's physical response to the mask placement was observed immediately and within 30 s of placement. The MAC of sevoflurane was measured using the up-and-down sequential method of Dixon. RESULTS: The calculated MAC of end-expiratory sevoflurane during laryngeal mask insertion in adult females was (2.94 ± 0.18)%, (2.69 ± 0.16)%, (2.32 ± 0.16)% and (1.83 ± 0.15)% in groups RF0, RF1, RF2 and RF3; (2.98 ± 0.18)%, (2.80 ± 0.19)%, (2.54 ± 0.15)% and (2.15 ± 0.15)% in male groups RM0, RM1, RM2 and RM3, respectively. The MAC values were significantly lower in the (RF1-RF3, RM1-RM3) group when compared to the (RF0, RM0) group. There was no significant difference between (RF0, RF1) and (RM0, RM1), but the MAC value of the RF2-RF3 group was significantly lower than that of the RM2-RM3 group. CONCLUSIONS: Remimazolam can effectively reduce end-expiratory sevoflurane MAC values during laryngeal mask placement in adults. When remimazolam was measured above 1.5 mg/kg/h, the effect of inhibiting laryngeal mask implantation in female patients was stronger than that in male patients. Remimazolam at a dose of 1-2 mg/kg/h combined with sevoflurane induction can be safely and effectively used in these patients.


Assuntos
Anestésicos Inalatórios , Máscaras Laríngeas , Éteres Metílicos , Adulto , Humanos , Masculino , Feminino , Sevoflurano , Benzodiazepinas
6.
Opt Express ; 31(12): 18824-18839, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381313

RESUMO

Traditional methods of coherent diffraction imaging using random masks result in an insufficient difference between the diffraction patterns, making it challenging to form a strong amplitude constraint, causing significant speckle noise in the measurement results. Hence, this study proposes an optimized mask design method combining random and Fresnel masks. Increasing the difference between diffraction intensity patterns enhances the amplitude constraint, suppresses the speckle noise effectively, and improves the phase recovery accuracy. The numerical distribution of the modulation masks is optimized by adjusting the combination ratio of the two mask modes. The simulation and physical experiments show that the reconstruction results of PSNR and SSIM using the proposed method are higher than those using random masks, and the speckle noises are effectively reduced.

7.
J Exp Bot ; 74(14): 4158-4168, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37022978

RESUMO

Extreme environmental changes threaten plant survival and worldwide food production. In response to osmotic stress, the plant hormone abscisic acid (ABA) activates stress responses and restricts plant growth. However, the epigenetic regulation of ABA signaling and crosstalk between ABA and auxin are not well known. Here, we report that the histone variant H2A.Z-knockdown mutant in Arabidopsis Col-0, h2a.z-kd, has altered ABA signaling and stress responses. RNA-sequencing data showed that a majority of stress-related genes are activated in h2a.z-kd. In addition, we found that ABA directly promotes the deposition of H2A.Z on SMALL AUXIN UP RNAs (SAURs), and that this is involved in ABA-repression of SAUR expression. Moreover, we found that ABA represses the transcription of H2A.Z genes through suppressing the ARF7/19-HB22/25 module. Our results shed light on a dynamic and reciprocal regulation hub through H2A.Z deposition on SAURs and ARF7/19-HB22/25-mediated H2A.Z transcription to integrate ABA/auxin signaling and regulate stress responses in Arabidopsis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Ácido Abscísico/metabolismo , Ácidos Indolacéticos/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Histonas/metabolismo , Epigênese Genética , RNA/metabolismo , Regulação da Expressão Gênica de Plantas
8.
Plant Cell ; 32(4): 888-903, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32075864

RESUMO

R-loops are a common chromatin feature with essential functions in multiple cellular processes and diseases. However, little is known about the dynamic patterns of R-loops in a given organism. Here, using our recently developed genome-wide R-loop profiling method, we generated a comprehensive atlas quantifying the R-loop patterns of Arabidopsis (Arabidopsis thaliana) in 53 samples during development and during responses to environmental stimuli. The R-loop patterns were fairly stable in plants at the vegetative stage and in response to different light spectra and other environmental stimuli. Notably, the R-loops showed turnover during the plant life cycle, with patterns switching between generations. Importantly, R-loop dynamics was not strongly associated with RNA abundance, indicating that the mechanisms regulating R-loop formation and RNA accumulation are independent. We also observed enrichment of R-loops in transcription factor binding regions, suggesting that R-loops could function as potential cis-transcriptional regulators. This study provides an overview of R-loop dynamics in Arabidopsis during development and stress responses, highlights the unique dynamics of R-loops in the flowering plant Arabidopsis, and lays the groundwork for elucidating the functions of R-loops.


Assuntos
Arabidopsis/genética , Arabidopsis/fisiologia , Meio Ambiente , Estruturas R-Loop/genética , Sequência Conservada , Lógica Fuzzy , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Loci Gênicos , Genoma de Planta , RNA Polimerase III/metabolismo , RNA de Plantas/genética , Sítio de Iniciação de Transcrição , Transcrição Gênica
9.
BMC Cancer ; 23(1): 677, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37464334

RESUMO

The accumulation of lipid droplets (LDs) in hepatocytes is the main pathogenesis in nonalcoholic fatty liver disease (NAFLD), which is also the key risk factor for the progression of hepatocellular carcinoma (HCC). LDs behaviors are demonstrated to be associated with HCC advancement, and are tightly regulated by a subset protein localized on the surface of LDs. However, the role of LDs-localized protein in HCC has been rarely investigated. This study is focused on the transcriptional dynamic and prognostic value of LDs-localized protein in HCC. Firstly, we summarized the known LDs-localized proteins, which are demonstrated by immunofluorescence according to previous studies. Next, by the use of GEPIA/UALCAN/The Human Protein Atlas databases, we screened the transcriptional change in tumor and normal liver tissues, and found that 13 LDs-localized proteins may involve in the progression of HCC. Then we verified the transcriptional changes of 13 LDs-localized proteins by the use of HCC samples. Moreover, based on the assays of fatty liver of mice and human NAFLD liver samples, we found that the hepatic steatosis mainly contributed to the transcriptional change of selected LDs-localized proteins, indicating the involvement of these LDs-localized proteins in the negative role of NAFLD in HCC progression. Finally, we focused on the role of PLIN3 in HCC, and revealed that NAFLD status significantly promoted PLIN3 transcription in HCC tissue. Functional studies revealed that PLIN3 knockdown significantly limited the migration and chemosensitivity of hepatoma cells, suggesting the positive role of PLIN3 in HCC progression. Our study not only revealed the transcriptional change and prognostic value of lipid droplet-localized proteins in HCC, but also built the correlation between HCC and hepatic steatosis.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Humanos , Carcinoma Hepatocelular/patologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Gotículas Lipídicas/metabolismo , Prognóstico , Proteínas Associadas a Gotículas Lipídicas/metabolismo , Neoplasias Hepáticas/patologia , Proteínas/metabolismo
10.
J Endocrinol Invest ; 46(4): 749-761, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36224454

RESUMO

BACKGROUND: Papillary thyroid cancer (PTC) is life-threatening due to its malignant progression. Considerable evidence demonstrates that circular RNA (circRNA) regulates PTC development. This study aims to explore the mechanism of circ_0000644 modulating PTC malignant progression. METHODS: The RNA levels of circ_0000644, microRNA-671-5p (miR-671-5p) and annexin A2 (ANXA2) were detected by quantitative real-time polymerase chain reaction. Western blot was performed to check protein expression. Cell proliferation and cell apoptosis were investigated by 5-ethynyl-29-deoxyuridine and flow cytometry. Angiogenic capacity, migration and invasion were analyzed by tube formation assay and transwell assay. The interaction between miR-671-5p and circ_0000644 or ANXA2 was identified by dual-luciferase reporter assay. Xenograft mouse model assay was performed to analyze the effect of circ_0000644 on tumor formation in vivo. RESULTS: Circ_0000644 and ANXA2 expression was significantly upregulated, while miR-671-5p was downregulated in PTC tissues and cells when compared with control groups. Circ_0000644 knockdown inhibited PTC cell proliferation, tube formation, migration, and invasion, but induced apoptosis in vitro. Moreover, circ_0000644 knockdown led to delayed tumorigenesis in vivo. In addition, circ_0000644 acted as a miR-671-5p sponge and mediated PTC cell tumor properties through miR-671-5p. ANXA2 was identified as a target gene of miR-671-5p, and its overexpression relieved miR-671-5p-induced effects in PTC cells. Furthermore, circ_0000644 depletion inhibited ANXA2 production by combining with miR-671-5p. CONCLUSION: Circ_0000644 depletion repressed PTC cell tumor properties through the miR-671-5p/ANXA2 axis.


Assuntos
Anexina A2 , MicroRNAs , Neoplasias da Glândula Tireoide , Humanos , Animais , Camundongos , Câncer Papilífero da Tireoide/genética , Anexina A2/genética , Carcinogênese , Proliferação de Células , Modelos Animais de Doenças , Neoplasias da Glândula Tireoide/genética , MicroRNAs/genética , Linhagem Celular Tumoral
11.
Anim Biotechnol ; 34(7): 2051-2058, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35491893

RESUMO

FOXO1 (FKHR) gene, as a transcription factor, plays a vital role in animal growth and development, participating in many biological processes. The aim of this study was to ascertain Insertion/deletions (Indels) polymorphism within bovine FoxO1 gene in 679 Chinese adult cows and associate them with stature traits. Two Indels (named as Indel-3 and Indel-4, recorded as rs383545622 and rs525318770 in NCBI, respectively) were successfully genotyped by the Once PCR method, which was reliable, rapid and cost effective for simultaneous detection of two or more Indels. Indel-3 and Indel-4 were located at the second intron. All four different haplotypes (H1: D3D4, H2: I3D4, H3: D3I4, H4: I3I4) could be identified, and the D (del-) allele, DD (del-/del-) genotype and D3D4 haplotype retained the highest frequency. However, individuals with DI (D3I3, D4I4 or H1H4/H2H3 genotype) showed significantly better phenotypic traits than those with the other genotypes in Nanyang cattle, showing a hybrid vigor. The results implied that this DI genotype can be applied to early selective breeding to improve the productivity of Nanyang cattle. Our results suggested that these two Indels within the bovine FoxO1 gene might be used as genetic markers for marker-assisted selection (MAS) in cattle breeding and genetics.


Assuntos
Fenômenos Biológicos , Proteína Forkhead Box O1 , Polimorfismo Genético , Animais , Bovinos/genética , Feminino , Cruzamento , Genótipo , Haplótipos/genética , Fenótipo , Polimorfismo de Nucleotídeo Único , Proteína Forkhead Box O1/genética
12.
Ren Fail ; 45(2): 2278301, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37994433

RESUMO

BACKGROUND: Conscious sedation anesthesia (CSA) is an anesthetic method during peritoneal dialysis catheter implantation. However, lack of optimal CSA strategies for patients with end-stage renal disease (ESRD). This study aimed to evaluate the analgesic effects and safety of CSA using different doses of remifentanil combined with dexmedetomidine during peritoneal dialysis catheter insertion. METHODS: Patients who underwent peritoneal dialysis (PD) catheter placement via open surgical incision were retrospectively analyzed and divided into three groups based on the tertile dose of remifentanil. The bispectral index (BIS) was used to monitor the depth of anesthesia. Data regarding clinical findings, the effects of anesthesia, and the incidence of drug-related adverse effects were collected. RESULTS: In total, 102 patients completed the surgery successfully and safely. The dose of remifentanil was 0.02-0.07 µg/kg/min, 0.08-0.13 µg/kg/min, and 0.14-0.20 µg/kg/min in Groups A, B, and C, respectively. Only seven patients reported mild pain during the surgery. No significant differences were observed among the numeric rating scale scores of the three groups (p > 0.05). Intraoperative hemodynamics were stable. The incidence of respiratory depression was 8.3%, 20.0%, and 41.9% in Groups A, B, and C, respectively (p < 0.01). The incidence of gastrointestinal symptoms in Group C (51.6%) was higher than that in Groups A and B (p < 0.05). CONCLUSION: Low-dose remifentanil (0.02-0.07 µg/kg/min) combined with dexmedetomidine achieved satisfactory anesthetic effects with fewer adverse drug reactions during PD catheter implantation, indicating its potential for use in patients undergoing PD catheter placement.


Assuntos
Anestesia , Dexmedetomidina , Diálise Peritoneal , Humanos , Remifentanil , Dexmedetomidina/efeitos adversos , Hipnóticos e Sedativos/efeitos adversos , Sedação Consciente/efeitos adversos , Sedação Consciente/métodos , Piperidinas/efeitos adversos , Estudos Retrospectivos , Catéteres
13.
Biochem Biophys Res Commun ; 623: 181-188, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35921710

RESUMO

Type I interferon pathway is a crucial component of innate immune signaling upon pathogen infection or endogenous instability. An imbalance of type I interferon can lead to many diseases, such as autoimmune diseases and inflammatory diseases. Meanwhile, the side effects of clinical drugs on type I interferon signaling may result in impaired outcomes in clinical treatment, especially in cancer immunotherapy which is associated with type I interferon signaling. Here, we found that sorafenib, an FDA-approved drug for HCC chemotherapy, suppresses both DNA- and RNA-sensing mediated type I interferon pathway. Mechanistically, sorafenib treatment induces the autophagic degradation of MAVS, cGAS, TBK1, and IRF3, and attenuates the signaling transduction. In addition, sorafenib also inhibits the recruiting of STING or MAVS with TBK1 and IRF3. This work reveals the negative role of sorafenib in the regulation of type I interferon pathway. Sorafenib treatment is not only a potential drug for autoimmune disease and inflammation diseases, but also needs to be noticed in HCC chemotherapy.


Assuntos
Carcinoma Hepatocelular , Interferon Tipo I , Neoplasias Hepáticas , Humanos , Imunidade Inata , Fator Regulador 3 de Interferon/metabolismo , Interferon Tipo I/metabolismo , Nucleotidiltransferases/metabolismo , Proteínas Serina-Treonina Quinases , Sorafenibe/farmacologia
14.
J Immunol ; 204(6): 1499-1507, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-32024699

RESUMO

As an important effector in response to various intracellular or extracellular stimuli, the NF-κB family extensively participates in a wide spectrum of biological events, and its dysregulation may result in many pathological conditions, such as microbial infection, tumor progression, and neurodegenerative disorders. Previous investigations showed that multiple types of ubiquitination play critical roles in the modulation of the NF-κB signaling pathway, yet the molecular mechanisms are still poorly understood. In the current study, we identified TRIM25, an E3 ubiquitin ligase, as a novel positive regulator in mediating NF-κB activation in human embryonic kidney 293T (HEK293T), HeLa cells, THP-1 cells, and PBMCs. The expression of TRIM25 promoted TNF-α-induced NF-κB signaling, whereas the knockdown had the opposite effect. Furthermore, TRIM25 interacted with TRAF2 and enhanced the K63-linked polyubiquitin chains attached to TRAF2. Moreover, TRIM25 bridged the interaction of TRAF2 and TAK1 or IKKß. To our knowledge, our study has identified a previously unrecognized role for TRIM25 in the regulation of NF-κB activation by enhancing the K63-linked ubiquitination of TRAF2.


Assuntos
Quinase I-kappa B/metabolismo , NF-kappa B/metabolismo , Fator 2 Associado a Receptor de TNF/metabolismo , Fatores de Transcrição/metabolismo , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Técnicas de Silenciamento de Genes , Células HEK293 , Células HeLa , Humanos , Leucócitos Mononucleares , Lisina/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Sistema de Sinalização das MAP Quinases/genética , Sistema de Sinalização das MAP Quinases/imunologia , Cultura Primária de Células , Células THP-1 , Fatores de Transcrição/genética , Proteínas com Motivo Tripartido/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitinação/genética , Ubiquitinação/imunologia
15.
Opt Express ; 29(8): 11793-11818, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33984954

RESUMO

Together, the number of waves, wave vectors, amplitudes, and additional phases constitute the coherent wave group configuration and determine the pattern of the interference field. Identifying an appropriate wave group configuration is key to generating vortex lattices via interferometry. Previous studies have approached this task by first assigning the four elements, then calibrating the vortex state of the interference field. However, this method has failed to progress beyond generating third-order vortex lattices, which are insufficient for some practical applications. Therefore, this study proposes a method for determining the proper wave group configurations corresponding to arbitrary-order vortex lattices. We adopt a goal-driven approach: First, we set a vortex lattice as the target field and model it, before decomposing the target field into a sum of multiple harmonics using Fourier transforms. These harmonics constitute the wave group required to generate the target vortex lattice. As vortex lattices of any order can be set as the target field, the proposed method is compatible with any mode order. Simulations and experiments were conducted for fourth- and fifth-order vortex lattices, thus demonstrating the effectiveness of the proposed method.

16.
Am J Emerg Med ; 50: 442-448, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34492589

RESUMO

OBJECTIVE: To evaluate effectiveness of combinational use of dexmedetomidine and ketamine (DEX-KET) for pediatric procedural sedation or premedication. METHODS: Relevant studies were identified after a literature search in electronic databases and study selection was based on precise eligibility criteria. Meta-analyses of mean differences were performed to examine differences in sedation onset and recovery times between DEX-KET and comparators. Changes from baseline in heart rate (HR), respiratory rate, oxygen saturation, and mean arterial pressure (MAP), were pooled. Meta-analyses of proportions were performed to estimate incidence of adverse events. RESULTS: 15 studies (1087 patients) were included. Onset of sedation was significantly shorter in DEX-KET than in DEX group. HR declined in DEX-KET group from start (-3.5 beats per minute (BPM) [95% CI: -5.1, -1.9]) through midpoint (-7.2 BPM [95% CI: -12.1, -2.3]) and at end of sedation (-8.7 BPM [95% CI: -13.1, -4.4]). Decrease in HR after DEX administration at start was -11.6 BPM [95% CI: -16.0, -7.1] and remained consistent afterward. There was no change in MAP during DEX-KET sedation. However, after DEX administration, MAP decreased by -6.9 [95% CI: -10.4, -3.3] at start, -7.8 [95% CI: -11.4, -4.2] at middle, and by -6.6 [95% CI: -14.4, 1.1] at end of sedation. Incidence of hypotension was 3% [95% CI: 0, 9] in DEX-KET, 7% [95% CI: 2, 14] in DEX, and 0% [95% CI: 0, 2] in KET groups. Incidence of bradycardia was 2% [95% CI: 0, 6] with DEX-KET and 12% [95% CI: 5, 20] with DEX. Incidence of oxygen desaturation was 3% [95% CI: 0, 8] in DEX-KET, 2% [95% CI: 0, 6] in DEX, 12% [95% CI: 5, 20] in KET, and 13% [95% CI: 6, 21] in PROP-KET groups. MIDA-KET sedation had 13% [95% CI: 4, 25] incidence of tachycardia. CONCLUSIONS: DEX-KET for pediatric sedation results in better sedation outcomes than DEX or KET by shortening onset of sedation and recovery while maintaining hemodynamic and respiratory stability with low incidence of adverse events. DEX sedation was associated with higher incidence of bradycardia. Higher incidence of oxygen desaturation was observed with KET and PROP-KET whereas MIDA-KET was associated with higher incidence of tachycardia.


Assuntos
Sedação Consciente , Dexmedetomidina/administração & dosagem , Hipnóticos e Sedativos/administração & dosagem , Ketamina/administração & dosagem , Pré-Medicação , Criança , Combinação de Medicamentos , Humanos
17.
Neurobiol Learn Mem ; 171: 107204, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32145405

RESUMO

Sleep plays a crucial role in memory consolidation. However, the influence of sleep on emotional memory consolidation in older adults, especially in the context of associative memory, which is more cognitively demanding than item memory, remains elusive. For this study we recruited young and older adults, and randomly assigned them into the sleep or wake condition. They were administrated a visual-spatial associative memory task, which required them to remember a picture and its location. We measured memory performance for positive, neutral, and negative stimuli before and after a 12-h interval of being awake or asleep. An accuracy analysis indicated a beneficial effect of sleep on location memory regardless of age and valence. In addition, in a more fine-grained analysis, the drift rate from diffusion modeling showed that sleep facilitated the consolidation of negative stimuli in young adults, while this emotion bias shifted to positive stimuli in older adults. Moreover, negative correlations were observed between the change of memory performance and sleep characteristics in older adults, indicating that more sleep results in fewer negative memories. Our results provide a relatively weak support for an age-related emotional bias in the context of associative memory, manifested in the absence of an age-by-valence interaction in accuracy, whilst a modeling parameter in consideration of both accuracy and response time yielded evidence consistent with the predictions of the socioemotional selectivity theory.


Assuntos
Aprendizagem por Associação/fisiologia , Consolidação da Memória/fisiologia , Memória/fisiologia , Sono/fisiologia , Vigília/fisiologia , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Adulto Jovem
18.
Ecotoxicol Environ Saf ; 195: 110445, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32203772

RESUMO

BACKGROUND: Polycyclic aromatic hydrocarbons (PAHs) exposure has been shown to be a risk factor for many diseases. However, studies on the association between PAHs exposure and kidney disease are limited. The aim of this study was to explore the association between urinary PAHs and albuminuria based on a national representative sample from the general U.S. METHOD: The data utilized were extracted from the 2003-2014 National Health and Nutrition Examination Survey (NHANES). Eight urinary PAHs were detected as PAH metabolites (OH-PAHs). Multivariable logistic regression analyses were applied to examine the association between urinary OH-PAHs and urinary albumin-creatinine ratio (ACR). All models were adjusted for confounding demographic, anthropometric and lifestyle factors. RESULT: A total of 8149 NHANES (2003-2014) participants with complete data were eligible. Compared with the lowest quartile, an increased prevalence of high ACR level (>3 mg/mmol) was observed in the participants with the highest quartile of 2-hydroxynaphthalene [OR (95% CI), 1.56 (1.28-1.90), P < 0.001], 3-hydroxyfluorene [OR (95% CI), 1.29 (1.06-1.58), P = 0.011] and 2-hydroxyfluorene [OR (95% CI), 1.47 (1.20-1.80), P < 0.001] levels after adjusting for confounding factors. In subgroup analysis, significantly high OH-PAHs leveland a strong relationship between OH-PAHs and ACR were observed in current smokers in the adjusted model. CONCLUSION: High levels of urinary OH-PAHs were positively associated with high levels of ACR in the U.S. POPULATION: Our finding provided evidence that PAHs exposure might potentially be related to albuminuria and therefore might have implications for environmental governance and prevention/treatment of this condition.


Assuntos
Albuminúria/urina , Exposição Ambiental/análise , Poluentes Ambientais/urina , Hidrocarbonetos Policíclicos Aromáticos/urina , Adulto , Albuminúria/epidemiologia , Biomarcadores/urina , Conservação dos Recursos Naturais , Política Ambiental , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Prevalência , Fatores de Risco , Estados Unidos/epidemiologia
19.
Opt Express ; 27(15): 21652-21666, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31510238

RESUMO

The number of zero lines of the real and imaginary parts of the optical vortex (OV), both are the same as the topological charge (TC), and all of these lines intersect at one point where the phase singularity is. Furthermore, zero crossings distribute regularly on the transverse plane of the OV lattice. Zero lines of the real and imaginary parts of the non-diffracting fields without OV that generated by multi-waves interference are periodic but coincident. We stack two groups of these kind of zero lines which can be regarded as a set of zero lines of the real part and a set of zero lines of the imaginary part respectively, to satisfy the cross state of zero lines of an OV lattice. Then two groups of multi-waves corresponding to the two fields can be obtained. The expected OV lattice that generated by the two groups of engineered waves interference together is validated through both numerical simulations and experiments.

20.
Clin Endocrinol (Oxf) ; 91(2): 348-355, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31050007

RESUMO

OBJECTIVE: The low pre- and intraoperative diagnostic rates in follicular thyroid carcinoma (FTC) often lead to inadequate surgical resection and necessitate further completion surgery. Therefore, the preoperative prediction of FTC in thyroid nodules is essential. DESIGN AND PATIENT: Patients were categorized into two data sets: the modelling data set, which included 3649 patients admitted to our centre between January 2014 and December 2016, and the validation data set, which included 1253 patients admitted between January and December 2017. Patient data from the FTC and non-FTC groups were initially included in a modelling data set to establish a preoperative prediction model. This model was subsequently employed in a validation data set for external validation of the predictive value. The positivity rate for FTC predicted by the model was compared with that of the intraoperative frozen sections. RESULTS: The preoperative serum thyroglobulin level, nodule diameter, calcification status, solidity and blood supply were selected as predictors for the model. The regression equation was as follows: Y = 0.010 × (thyroglobulin level) + 0.556 × (nodule diameter) + 0.675 × (calcification status) + 2.355 × (nodule component) + 1.072*(blood flow) - 9.787. The model positively predicted FTC at values of Y ≥ -4.11. The accuracy, sensitivity, specificity, positive likelihood ratio and negative likelihood ratio of the prediction model were 89.2%, 90.2%, 87.7%, 39.2 and 0.11, respectively. External validation of the model demonstrated acceptable results. The positive prediction rate of the model was 90.7% (78/86), which was significantly higher than that of the intraoperative frozen sections (10.5% [9/86]; P < 0.0001). CONCLUSIONS: We successfully established and validated a simple and reliable preoperative prediction model for FTC using the preoperative thyroglobulin level and ultrasonographic features of the thyroid nodules. This model may improve the preoperative evaluation of FTC in clinical settings and facilitate the development of a reasonable surgical programme for FTC.


Assuntos
Adenocarcinoma Folicular/patologia , Adenocarcinoma Folicular/cirurgia , Modelos Biológicos , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Nódulo da Glândula Tireoide/patologia , Adenocarcinoma Folicular/diagnóstico por imagem , Humanos , Funções Verossimilhança , Valor Preditivo dos Testes , Cuidados Pré-Operatórios , Curva ROC , Análise de Regressão , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/cirurgia , Ultrassonografia
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