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1.
Nucleic Acids Res ; 51(2): 595-609, 2023 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-36629271

RESUMO

Protein translation is tightly and precisely controlled by multiple mechanisms including upstream open reading frames (uORFs), but the origins of uORFs and their role in maize are largely unexplored. In this study, an active transposition event was identified during the propagation of maize inbred line B73. The transposon, which was named BTA for 'B73 active transposable element hAT', creates a novel dosage-dependent hypomorphic allele of the hexose transporter gene ZmSWEET4c through insertion within the coding sequence in the first exon, and results in reduced kernel size. The BTA insertion does not affect transcript abundance but reduces protein abundance of ZmSWEET4c, probably through the introduction of a uORF. Furthermore, the introduction of BTA sequence in the exon of other genes can regulate translation efficiency without affecting their mRNA levels. A transposon capture assay revealed 79 novel insertions for BTA and BTA-like elements. These insertion sites have typical euchromatin features, including low levels of DNA methylation and high levels of H3K27ac. A putative autonomous element that mobilizes BTA and BTA-like elements was identified. Together, our results suggest a transposon-based origin of uORFs and document a new role for transposable elements to influence protein abundance and phenotypic diversity by affecting the translation rate.


Assuntos
Biossíntese de Proteínas , Alelos , Sequência de Bases , RNA Mensageiro/genética , Fases de Leitura Aberta/genética
2.
Biotechnol Bioeng ; 121(6): 1831-1845, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38454569

RESUMO

Raman spectroscopy has found widespread usage in monitoring cell culture processes both in research and practical applications. However, commonly, preprocessing methods, spectral regions, and modeling parameters have been chosen based on experience or trial-and-error strategies. These choices can significantly impact the performance of the models. There is an urgent need for a simple, effective, and automated approach to determine a suitable procedure for constructing accurate models. This paper introduces the adoption of a design of experiment (DoE) method to optimize partial least squares models for measuring the concentration of different components in cell culture bioreactors. The experimental implementation utilized the orthogonal test table L25(56). Within this framework, five factors were identified as control variables for the DoE method: the window width of Savitzky-Golay smoothing, the baseline correction method, the order of preprocessing steps, spectral regions, and the number of latent variables. The evaluation method for the model was considered as a factor subject to noise. The optimal combination of levels was determined through the signal-to-noise ratio response table employing Taguchi analysis. The effectiveness of this approach was validated through two cases, involving different cultivation scales, different Raman spectrometers, and different analytical components. The results consistently demonstrated that the proposed approach closely approximated the global optimum, regardless of data set size, predictive components, or the brand of Raman spectrometer. The performance of models recommended by the DoE strategy consistently surpassed those built using raw data, underscoring the reliability of models generated through this approach. When compared to exhaustive all-combination experiments, the DoE approach significantly reduces calculation times, making it highly practical for the implementation of Raman spectroscopy in bioprocess monitoring.


Assuntos
Reatores Biológicos , Técnicas de Cultura de Células , Análise Espectral Raman , Análise Espectral Raman/métodos , Técnicas de Cultura de Células/métodos , Modelos Biológicos , Células CHO , Cricetulus , Animais
3.
Eur Radiol ; 34(3): 1481-1492, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37796294

RESUMO

OBJECTIVES: Sonochemotherapy, which uses microbubble (MB)-assisted ultrasound (US) to deliver chemotherapeutic agents, has the potential to enhance tumour chemotherapy. The combination of US and MB has been demonstrated to prolong the survival of patients with pancreatic cancer. This phase 2 clinical trial aimed to determine the clinical efficacy and safety of sonochemotherapy for inoperable pancreatic ductal adenocarcinoma by using US and MB. METHODS: Eighty-two patients with stage III or IV pancreatic cancer were recruited from July 2018 to March 2021 and followed up until September 2022. US treatment was performed with a modified diagnostic US scanner for 30 min after chemotherapeutic infusion. The primary endpoint was overall survival (OS), and the secondary endpoints were Eastern Cooperative Oncology Group (ECOG) status < 2, progression-free survival (PFS), disease control rate (DCR), and adverse events. RESULTS: Seventy-eight patients were randomly allocated (40 to chemotherapy and 38 to sonochemotherapy). The median OS was longer with sonochemotherapy than with chemotherapy (9.10 vs. 6.10 months; p = 0.037). The median PFS with sonochemotherapy was 5.50 months, compared with 3.50 months (p = 0.080) for chemotherapy. The time of ECOG status < 2 was longer with sonochemotherapy (7.20 months) than with chemotherapy (5.00 months; p = 0.029). The DCR was 73.68% for sonochemotherapy compared with 42.50% for the control (p = 0.005). The incidence of overall adverse events was balanced between the two groups. CONCLUSIONS: The use of sonochemotherapy can extend the survival and well-being time of stage III or IV pancreatic cancer patients without any increase in serious adverse events. TRIAL REGISTRATION: ChineseClinicalTrials.gov ChiCTR2100044721 CLINICAL RELEVANCE STATEMENT: This multicentre, randomised, controlled trial has proven that sonochemotherapy, namely, the combination of diagnostic ultrasound, microbubbles, and chemotherapy, could extend the overall survival of patients with end-stage pancreatic ductal adenocarcinoma from 6.10 to 9.10 months without increasing any serious adverse events. KEY POINTS: • This is the first multicentre, randomised, controlled trial of sonochemotherapy for clinical pancreatic cancer treatment using ultrasound and a commercial ultrasound contrast agent. • Sonochemotherapy extended the median overall survival from 6.10 (chemotherapy alone) to 9.10 months. • The disease control rate increased from 42.50% with chemotherapy to 73.68% with sonochemotherapy.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Microbolhas , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/tratamento farmacológico , Resultado do Tratamento , Carcinoma Ductal Pancreático/diagnóstico por imagem , Carcinoma Ductal Pancreático/terapia , Ultrassonografia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
4.
Artigo em Inglês | MEDLINE | ID: mdl-38801487

RESUMO

PURPOSE: The objective of this study was to examine the molecular epidemiology and clinical characteristics of HMPV infection among children with ARIs in Nanjing. METHODS: The respiratory samples were collected from 2078 children (≤ 14 years) with acute respiratory infections and were tested for HMPV using real-time RT-PCR. Amplification and sequencing of the HMPV G gene were followed by phylogenetic analysis using MEGA 7.0. RESULT: The detection rate of HMPV among children was 4.7% (97/2078), with a concentration in those under 5 years of age. Notably, the peak season for HMPV prevalence was observed in winter. Among the 97 HMPV-positive samples, 51.5% (50/97) were available for characterization of the HMPV G protein gene. Phylogenetic analysis indicated that the sequenced HMPV strains were classified into three sublineages: A2c111nt - dup (84.0%), B1 (2.0%), and B2 (14.0%). CONCLUSION: There was an incidence of HMPV among hospitalized children during 2021-2022 in Nanjing with A2c111nt - dup being the dominant strain. This study demonstrated the molecular epidemiological characteristics of HMPV among children with respiratory infections in Nanjing, China.

5.
BMC Infect Dis ; 24(1): 583, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867161

RESUMO

OBJECTIVE: The objective of this study was to conduct a comprehensive analysis of the molecular transmission networks and transmitted drug resistance (TDR) patterns among individuals newly diagnosed with HIV-1 in Nanjing. METHODS: Plasma samples were collected from newly diagnosed HIV patients in Nanjing between 2019 and 2021. The HIV pol gene was amplified, and the resulting sequences were utilized for determining TDR, identifying viral subtypes, and constructing molecular transmission network. Logistic regression analyses were employed to investigate the epidemiological characteristics associated with molecular transmission clusters. RESULTS: A total of 1161 HIV pol sequences were successfully extracted from newly diagnosed individuals, each accompanied by reliable epidemiologic information. The analysis revealed the presence of multiple HIV-1 subtypes, with CRF 07_BC (40.57%) and CRF01_AE (38.42%) being the most prevalent. Additionally, six other subtypes and unique recombinant forms (URFs) were identified. The prevalence of TDR among the newly diagnosed cases was 7.84% during the study period. Employing a genetic distance threshold of 1.50%, the construction of the molecular transmission network resulted in the identification of 137 clusters, encompassing 613 nodes, which accounted for approximately 52.80% of the cases. Multivariate analysis indicated that individuals within these clusters were more likely to be aged ≥ 60, unemployed, baseline CD4 cell count ≥ 200 cells/mm3, and infected with the CRF119_0107 (P < 0.05). Furthermore, the analysis of larger clusters revealed that individuals aged ≥ 60, peasants, those without TDR, and individuals infected with the CRF119_0107 were more likely to be part of these clusters. CONCLUSIONS: This study revealed the high risk of local HIV transmission and high TDR prevalence in Nanjing, especially the rapid spread of CRF119_0107. It is crucial to implement targeted interventions for the molecular transmission clusters identified in this study to effectively control the HIV epidemic.


Assuntos
Farmacorresistência Viral , Infecções por HIV , HIV-1 , Humanos , HIV-1/genética , HIV-1/classificação , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Infecções por HIV/virologia , Masculino , Feminino , Adulto , China/epidemiologia , Pessoa de Meia-Idade , Farmacorresistência Viral/genética , Adulto Jovem , Prevalência , Genótipo , Filogenia , Adolescente , Epidemiologia Molecular , Produtos do Gene pol do Vírus da Imunodeficiência Humana/genética , Idoso
6.
J Ultrasound Med ; 43(2): 253-263, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37853950

RESUMO

OBJECTIVES: To investigate the appropriate combination of pulse length (PL) and pulse repetition frequency (PRF) when performing ultrasound stimulated microbubble (USMB) to enhance doxorubicin (DOX) delivery to tumors. METHODS: A total of 48 tumor-bearing mice were divided into four groups, namely groups A-D. The mice in groups B-D were treated with chemotherapy and USMB treatment with different combinations of PL and PRF, and group A was control. Contrast-enhanced ultrasound imaging was conducted to analyze tumor blood perfusion. Fluorescence microscopy and high-performance liquid chromatography were used to qualitatively and quantitatively analyse DOX release. The structural changes of tumors were observed under light microscope and transmission electron microscope. Furthermore, another 24 tumor-bearing mice were treated with sonochemotherapy and some related inflammatory factors were measured to explore the underlying mechanism. RESULTS: With PL of three cycles and PRF of 2 kHz, the tumor perfusion area ratio increased by 26.67%, and the DOX concentration was 4.69 times higher than the control (P < .001). With PL of 34.5 cycles and PRF of 200 Hz, the tumor perfusion area ratio decreased by 12.7% and DOX did not exhibit increased extravasation compared with the control. Microvascular rupture and hemorrhage were observed after long PL and low PRF treatment. While vasodilation and higher levels of some vasodilator inflammatory factors were found after treatment with short PL and high PRF. CONCLUSIONS: USMB treatment using short PL and high PRF could enhance tumor blood perfusion and increase DOX delivery, whereas long PL and low PRF could not serve the same purpose.


Assuntos
Doxorrubicina , Neoplasias , Camundongos , Animais , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Ultrassonografia/métodos , Perfusão , Microbolhas
7.
Horm Metab Res ; 55(11): 758-764, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37903496

RESUMO

The abnormal hemoglobin (HGB) and serum lipid concentrations during pregnancy will increase the risk of preterm delivery. Our study aimed to explore the correlation between prenatal HGB and serum lipid levels and preterm delivery. We enrolled 215 mother-infant pairs in a pilot cohort study. The logistic regression model and Restricted Cubic Spline model (RCS) were used to investigate the levels of prenatal blood HGB and serum lipid such as triglyceride (TG), total cholesterol, high-density lipoprotein, low density lipoprotein and preterm delivery. The results showed that moderate levels of prenatal blood HGB (OR=0.28; 95%CI: 0.10, 0.75, p-trend=0.018) and high level of serum TG (OR=0.29; 95%CI: 0.10, 0.84, p-trend=0.022) level were negatively associated with the risk of preterm delivery. The joint effect results showed that compared with lower level of prenatal blood HGB (≤123.13 g/l) and TG (≤3.7 mmol/l), we found that high levels prenatal blood HGB and serum TG (OR=0.32, 95%CI: 0.12, 0.89) had a negative association with the risk of preterm delivery. Moreover, prenatal blood HGB and serum TG levels had negative linear dose-effect relationships with the risk of preterm delivery in overall and girl group (p<0.05). Moderate levels of prenatal blood HGB and high level of serum TG were negatively associated with the risk of preterm delivery. The joint effect of high levels prenatal HGB and prenatal serum TG in the normal range were negatively correlated with preterm delivery. Moreover, the underlying mechanisms should be clarified in future studies.


Assuntos
Nascimento Prematuro , Gravidez , Recém-Nascido , Feminino , Humanos , Projetos Piloto , Triglicerídeos , Lipoproteínas HDL , Hemoglobinas
8.
Molecules ; 28(11)2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37298870

RESUMO

Biosensors show promising prospects in the assays of various targets due to their advantages of high sensitivity, good selectivity and rapid response. Molecular recognition is a key event of biosensors, which usually involves the interaction of antigen-antibody, aptamer-target, lectin-sugar, boronic acid-diol, metal chelation and DNA hybridization. Metal ions or complexes can specifically recognize phosphate groups in peptides or proteins, obviating the use of biorecognition elements. In this review, we summarized the design and applications of biosensors with metal ion-phosphate chelation interaction for molecular recognition. The sensing techniques include electrochemistry, fluorescence, colorimetry and so on.


Assuntos
Técnicas Biossensoriais , Fosfatos , Técnicas Biossensoriais/métodos , Oligonucleotídeos , Hibridização de Ácido Nucleico , Metais/química , Íons
9.
Soft Matter ; 18(40): 7699-7734, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36205123

RESUMO

Compared to traditional rigid-bodied robots, soft robots are constructed using physically flexible/elastic bodies and electronics to mimic nature and enable novel applications in industry, healthcare, aviation, military, etc. Recently, the fabrication of robots on soft matter with great flexibility and compliance has enabled smooth and sophisticated 'multi-degree-of-freedom' 3D actuation to seamlessly interact with humans, other organisms and non-idealized environments in a highly complex and controllable manner. Herein, we summarize the fabrication approaches, driving strategies, novel applications, and future trends of soft robots. Firstly, we introduce the different fabrication approaches to prepare soft robots and compare and systematically discuss their advantages and disadvantages. Then, we present the actuator-based and material-based driving strategies of soft robotics and their characteristics. The representative applications of soft robotics in artificial intelligence, medicine, sensors, and engineering are summarized. Also, some remaining challenges and future perspectives in soft robotics are provided. This work highlights the recent advances of soft robotics in terms of functional material selection, structure design, control strategies and biomimicry, providing useful insights into the development of next-generation functional soft robotics.


Assuntos
Biomimética , Robótica , Humanos , Inteligência Artificial , Eletrônica
10.
Langmuir ; 37(28): 8410-8416, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34213347

RESUMO

Strong, reversible, and self-cleaning adhesion in the toe pads of geckos allow the lizards to climb on a variety of vertical and inverted surfaces, regardless of the surface conditions, whether hydrophobic or hydrophilic, smooth or tough, wet or dry, clean or dirty. Development of synthetic gecko-inspired surfaces has drawn a great attention over the past two decades. Despite many external-stimuli responsive mechanisms (i.e., thermal, electrical, magnetic) have been successfully demonstrated, smart adhesives controlled by light signals still substantially lag behind. Here, in this report, we integrate tetramethylpiperidinyloxyl (TEMPO)-doped polydopamine (PDA), namely, TDPDA, with PDMS micropillars using a template-assisted casting method, to achieve both improved adhesion and self-cleaning performances. To the best of our knowledge, this is the first report on PDA being used as a doping nanoparticle in bioinspired adhesive surfaces to achieve highly efficient self-cleaning controllable by light signals. Notably, the adhesion of the 5% TDPDA-PDMS sample is ∼688.75% higher than that of the pure PDMS at the individual pillar level, which helps to explain the highly efficient self-cleaning mechanism. The sample surfaces (named TDPDA-PDMS) can efficiently absorb 808 nm wavelength of light and heat up from 25 °C to 80.9 °C in 3 min with NIR irradiation. The temperature rise causes significant reduction of adhesion, which results in outstanding self-cleaning rate of up to 55.8% within five steps. The exploration of the photoenabled switching mechanism with outstanding sensitivity may bring the biomimetic smart surfaces into a new dimension, rendering varied applications, e.g., in miniaturized climbing robot, artificial intelligence programmable manipulation/assembly/filtration, active self-cleaning solar panels, including high output sensors and devices in many engineering and biomedical frontiers.


Assuntos
Inteligência Artificial , Lagartos , Adesividade , Adesivos , Animais , Biomimética
11.
Proc Natl Acad Sci U S A ; 115(26): E6075-E6084, 2018 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-29891689

RESUMO

Photosystem II (PSII), a multisubunit protein complex of the photosynthetic electron transport chain, functions as a water-plastoquinone oxidoreductase, which is vital to the initiation of photosynthesis and electron transport. Although the structure, composition, and function of PSII are well understood, the mechanism of PSII biogenesis remains largely elusive. Here, we identified a nuclear-encoded pentatricopeptide repeat (PPR) protein LOW PHOTOSYNTHETIC EFFICIENCY 1 (LPE1; encoded by At3g46610) in Arabidopsis, which plays a crucial role in PSII biogenesis. LPE1 is exclusively targeted to chloroplasts and directly binds to the 5' UTR of psbA mRNA which encodes the PSII reaction center protein D1. The loss of LPE1 results in less efficient loading of ribosome on the psbA mRNA and great synthesis defects in D1 protein. We further found that LPE1 interacts with a known regulator of psbA mRNA translation HIGH CHLOROPHYLL FLUORESCENCE 173 (HCF173) and facilitates the association of HCF173 with psbA mRNA. More interestingly, our results indicate that LPE1 associates with psbA mRNA in a light-dependent manner through a redox-based mechanism. This study enhances our understanding of the mechanism of light-regulated D1 synthesis, providing important insight into PSII biogenesis and the functional maintenance of efficient photosynthesis in higher plants.


Assuntos
Proteínas de Arabidopsis/biossíntese , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Fatores de Iniciação em Eucariotos/metabolismo , Regulação da Expressão Gênica de Plantas , Luz , Proteínas de Membrana Transportadoras/metabolismo , Complexo de Proteína do Fotossistema II/biossíntese , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Fatores de Iniciação em Eucariotos/genética , Proteínas de Membrana Transportadoras/genética , Complexo de Proteína do Fotossistema II/genética
12.
J Sports Sci ; 39(14): 1621-1632, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33629647

RESUMO

The current study examined the effects of an 11-week exercise intervention on brain activity during a working memory (WM) task and resting-state functional network connectivity in deaf children. Twenty-six deaf children were randomly assigned to either an 11-week exercise intervention or control conditions. Before and after the exercise intervention, all participants were scanned with functional magnetic resonance imaging (fMRI) during N-back task performance and a resting state. The behavioural results showed that the exercise intervention improved WM performance. Task activation analyses showed an increase in the parietal, occipital, and temporal gyri and hippocampus and hippocampus (HIP). In addition, WM performance improvements were associated with greater activation in the left HIP region. Resting-state functional connectivity (Rs-FC) between HIP and certain other brain areas shown a significant interaction of group (exercise versus no exercise) and time (pre- and postintervention). Moreover, connectivity between the left HIP and left middle frontal gyrus was related to improved WM performance. These data extend current knowledge by indicating that an exercise intervention can improve WM in deaf children, and these enhancements may be related to the WM network plasticity changes induced by exercise.


Assuntos
Crianças com Deficiência , Exercício Físico/fisiologia , Memória de Curto Prazo/fisiologia , Plasticidade Neuronal/fisiologia , Pessoas com Deficiência Auditiva , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos
13.
Int J Mol Sci ; 22(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34502213

RESUMO

Bone marrow stromal cell antigen 2 (BST-2), also known as CD317 or tetherin, has been identified as a host restriction factor that suppresses the release of enveloped viruses from host cells by physically tethering viral particles to the cell surface; however, this host defense can be subverted by multiple viruses. For example, human immunodeficiency virus (HIV)-1 encodes a specific accessory protein, viral protein U (Vpu), to counteract BST-2 by binding to it and directing its lysosomal degradation. Thus, blocking the interaction between Vpu and BST-2 will provide a promising strategy for anti-HIV therapy. Here, we report a NanoLuc Binary Technology (NanoBiT)-based high-throughput screening assay to detect inhibitors that disrupt the Vpu-BST-2 interaction. Out of more than 1000 compounds screened, four inhibitors were identified with strong activity at nontoxic concentrations. In subsequent cell-based BST-2 degradation assays, inhibitor Y-39983 HCl restored the cell-surface and total cellular level of BST-2 in the presence of Vpu. Furthermore, the Vpu-mediated enhancement of pesudotyped viral particle production was inhibited by Y-39983 HCl. Our findings indicate that our newly developed assay can be used for the discovery of potential antiviral molecules with novel mechanisms of action.


Assuntos
Fármacos Anti-HIV/farmacologia , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Ensaios de Triagem em Larga Escala/métodos , Proteínas do Vírus da Imunodeficiência Humana/antagonistas & inibidores , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Proteínas Virais Reguladoras e Acessórias/antagonistas & inibidores , Antígenos CD/metabolismo , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas Ligadas por GPI/metabolismo , Infecções por HIV/metabolismo , Infecções por HIV/virologia , Células HeLa , Proteínas do Vírus da Imunodeficiência Humana/metabolismo , Humanos , Nanotecnologia/métodos , Proteínas Virais Reguladoras e Acessórias/metabolismo , Replicação Viral
14.
J Med Virol ; 92(12): 3237-3245, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32275071

RESUMO

To understand the epidemiology, evolutionary and transmission characteristics of HIV-1 CRF07_BC in Nanjing, China. One hundred and fifty-nine patients with HIV-1 CRF07_BC were recruited. DNA sequencing, phylogenetic analysis, and molecular transmission cluster analysis were conducted to determine the molecular epidemiology and evolutionary characteristics. Of these HIV-1-infected patients, 95.6% were male, and men who sex with men (76.7%) were the main transmission route. Only 34.0% of these cases were born in Nanjing, and most of them (64.8%) reported having multiple sex partners in the last 6 months. The maximum likelihood phylogenetic analyses of HIV-1 CRF07_BC revealed two lineages. Overall, 67.3% of Nanjing sequences were connected to at least one other individual distributed in 11 clusters, and the average degree was 21.2 with range (1-178). The clustered patients were more likely to be male. The time to a most recent common ancestor for the early HIV-1 CRF07_BC circulating in Nanjing was estimated to be 1998.71[1997.36-2001.07]. The mean estimated evolutionary rate for the epidemic cluster was slightly lower at 2.38[2.12-2.65] × 10-3 per site per year with the relaxed exponential clock model. HIV-1 CRF07_BC was transmitted into Nanjing more than 20 years ago from Yunnan and has become one of the most predominant subtypes with a higher evolutionary rate than before.

15.
J Integr Plant Biol ; 62(9): 1418-1432, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31944575

RESUMO

The balance between cellular carbon (C) and nitrogen (N) must be tightly coordinated to sustain optimal growth and development in plants. In chloroplasts, photosynthesis converts inorganic C to organic C, which is important for maintenance of C content in plant cells. However, little is known about the role of chloroplasts in C/N balance. Here, we identified a nuclear-encoded protein LOW PHOTOSYNTHETIC EFFICIENCY2 (LPE2) that it is required for photosynthesis and C/N balance in Arabidopsis. LPE2 is specifically localized in the chloroplast. Both loss-of-function mutants, lpe2-1 and lpe2-2, showed lower photosynthetic activity, characterized by slower electron transport and lower PSII quantum yield than the wild type. Notably, LPE2 is predicted to encode the plastid ribosomal protein S21 (RPS21). Deficiency of LPE2 significantly perturbed the thylakoid membrane composition and plastid protein accumulation, although the transcription of plastid genes is not affected obviously. More interestingly, transcriptome analysis indicated that the loss of LPE2 altered the expression of C and N response related genes in nucleus, which is confirmed by quantitative real-time-polymerase chain reaction. Moreover, deficiency of LPE2 suppressed the response of C/N balance in physiological level. Taken together, our findings suggest that LPE2 plays dual roles in photosynthesis and the response to C/N balance.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Carbono/metabolismo , Cloroplastos/metabolismo , Nitrogênio/metabolismo , Plastídeos/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Fotossíntese/genética , Fotossíntese/fisiologia
16.
Langmuir ; 34(46): 13882-13887, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30336049

RESUMO

The adhesion energy of kerogen in continental and marine shale was innovatively discovered using the colloid probe technique with atomic-force microscopy (AFM). AFM results indicated that the adhesion force of kerogen was higher than the inorganic material in both the continental and marine shale samples. The chemical elements in the two kinds of samples were measured by energy-dispersive X-ray analysis with scanning electron microscopy (SEM). The chemical compositions of kerogen involved C═C bonding, C═O bonding, pyridine nitrogen, and pyrrole nitrogen, whereas the primary constituent involving inorganic matter was Si-O bonding. These results were confirmed by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The high percentages of C═C and C═O bonding in kerogen are attributed to the large dipole on the kerogen surface which allowed kerogen to contain liquid and gaseous hydrocarbons.

17.
Neural Plast ; 2018: 3735208, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29853843

RESUMO

This study examined the effects of an 11-week aerobic exercise intervention on executive function (EF) and white matter integrity (WMI). In total, 28 deaf children (aged 9-13 years) were randomly assigned to either an 11-week exercise intervention or the control group. All the children had behavioral assessment and diffusion tensor imaging prior to and following the exercise intervention. The behavioral performance results demonstrated that EF was enhanced by exercise. Relative to the control group, WMI of the exercise intervention group showed (1) lower fractional anisotropy (FA) in the pontine crossing tract (PCT) and right cingulum (hippocampus) (CH), genu of the corpus callosum (gCC), right inferior cerebellar peduncle (ICP), left superior corona radiata (SCR), and left superior frontooccipital fasciculus (SFOF); (2) higher mean diffusivity (MD) in the gCC, right CH, right inferior frontooccipital fasciculus (IFOF), and left anterior limb of the internal capsule (ALIC); and (3) lower MD in the left ICP and left tapetum (TAP). Furthermore, the lower FA in gCC showed a significant negative correlation with improvement in behavioral performance, but the correlation was not significant after FDR correction. These results suggest that exercise can effectively improve deaf children's EF and reshape the WMI in deaf children. The improved EF by exercise is not related to a reshaping of WMI, but more studies on the relationship between EF and WMI by exercise may be needed.


Assuntos
Surdez/diagnóstico por imagem , Função Executiva/fisiologia , Exercício Físico/fisiologia , Substância Branca/diagnóstico por imagem , Substância Branca/fisiologia , Adolescente , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Criança , Surdez/psicologia , Surdez/terapia , Exercício Físico/psicologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Gravidez
18.
Plant Physiol ; 172(3): 1720-1731, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27609860

RESUMO

Maximizing light capture by light-harvesting pigment optimization represents an attractive but challenging strategy to improve photosynthetic efficiency. Here, we report that loss of a previously uncharacterized gene, HIGH PHOTOSYNTHETIC EFFICIENCY1 (HPE1), optimizes light-harvesting pigments, leading to improved photosynthetic efficiency and biomass production. Arabidopsis (Arabidopsis thaliana) hpe1 mutants show faster electron transport and increased contents of carbohydrates. HPE1 encodes a chloroplast protein containing an RNA recognition motif that directly associates with and regulates the splicing of target RNAs of plastid genes. HPE1 also interacts with other plastid RNA-splicing factors, including CAF1 and OTP51, which share common targets with HPE1. Deficiency of HPE1 alters the expression of nucleus-encoded chlorophyll-related genes, probably through plastid-to-nucleus signaling, causing decreased total content of chlorophyll (a+b) in a limited range but increased chlorophyll a/b ratio. Interestingly, this adjustment of light-harvesting pigment reduces antenna size, improves light capture, decreases energy loss, mitigates photodamage, and enhances photosynthetic quantum yield during photosynthesis. Our findings suggest a novel strategy to optimize light-harvesting pigments that improves photosynthetic efficiency and biomass production in higher plants.


Assuntos
Arabidopsis/fisiologia , Complexos de Proteínas Captadores de Luz/metabolismo , Fotossíntese , Pigmentos Biológicos/metabolismo , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Biomassa , Metabolismo dos Carboidratos/efeitos da radiação , Núcleo Celular/metabolismo , Núcleo Celular/efeitos da radiação , Clorofila/metabolismo , Regulação para Baixo/genética , Regulação para Baixo/efeitos da radiação , Genes de Plantas , Luz , Metaboloma/efeitos da radiação , Mutação/genética , Fotossíntese/efeitos da radiação , Plastídeos/genética , Plastídeos/efeitos da radiação , Splicing de RNA/genética , Splicing de RNA/efeitos da radiação , Tilacoides/metabolismo , Tilacoides/efeitos da radiação
19.
J Thromb Thrombolysis ; 44(1): 48-56, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28417266

RESUMO

The mechanism of ultrasound thrombolysis (UT) is generally attributed to cavitation. The insufficiency of microbubbles (MB) to serve as cavitation nuclei in the vessel-obstructing thrombi significantly reduces the effectiveness of UT. Taking advantage of the widely performed catheter-directed therapy (CDT), in a thrombo-embolized rabbit IVC model with a simultaneous catheter directed rt-PA thrombolysis procedure, guided moderate mechanical index longer pulses from a modified diagnostic ultrasound transducer, combined with an intraclot infusion of MB, significantly accelerated the thrombolysis process. The higher thrombolysis efficacy score and consistent elevated post-treatment plasma concentration level of D-Dimer, a product of fibrinolysis, both indicated the superiority of CDT + UT over CDT/UT alone. Pathologic examination of the treated occluded IVC segments revealed an almost complete dissolution of the thrombi treated with CDT + UT. There was no evidences of thrombo-embolism or local thrombus formation in the cardiac-pulmonary vessels. Combined with intraclot infusion of MB, guided longer pulse ultrasound from a diagnostic transducer is able to safely and significantly improve a catheter-directed thrombolysis procedure. It thus has the potential to achieve earlier clot removal, administration of a lower dosage of thrombolytic agent and, consequently, a lower incidence of thrombolysis-related side effects.


Assuntos
Cateterismo , Meios de Contraste/farmacologia , Ecocardiografia Doppler em Cores , Fibrinólise , Trombólise Mecânica , Microbolhas , Animais , Cateterismo/instrumentação , Cateterismo/métodos , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Masculino , Trombólise Mecânica/instrumentação , Trombólise Mecânica/métodos , Coelhos
20.
PLoS Pathog ; 10(5): e1004097, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24788758

RESUMO

Following Schistosoma japonicum (S. japonicum) infection, granulomatous responses are induced by parasite eggs trapped in host organs, particular in the liver, during the acute stage of disease. While excessive liver granulomatous responses can lead to more severe fibrosis and circulatory impairment in chronically infected host. However, the exact mechanism of hepatic granuloma formation has remained obscure. In this study, we for the first time showed that follicular helper T (Tfh) cells are recruited to the liver to upregulate hepatic granuloma formation and liver injury in S. japonicum-infected mice, and identified a novel function of macrophages in Tfh cell induction. In addition, our results showed that the generation of Tfh cells driven by macrophages is dependent on cell-cell contact and the level of inducible costimulator ligand (ICOSL) on macrophages which is regulated by CD40-CD40L signaling. Our findings uncovered a previously unappreciated role for Tfh cells in liver pathology caused by S. japonicum infection in mice.


Assuntos
Granuloma/imunologia , Hepatopatias Parasitárias/imunologia , Schistosoma japonicum/patogenicidade , Esquistossomose Japônica/imunologia , Linfócitos T Auxiliares-Indutores/fisiologia , Animais , Células Cultivadas , Granuloma/parasitologia , Ligante Coestimulador de Linfócitos T Induzíveis/genética , Fígado/imunologia , Fígado/parasitologia , Fígado/patologia , Hepatopatias Parasitárias/parasitologia , Macrófagos/imunologia , Macrófagos/parasitologia , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Schistosoma japonicum/imunologia , Esquistossomose Japônica/patologia , Caramujos/parasitologia
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