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1.
J Biol Chem ; : 107405, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38788853

RESUMO

Exogenous omega-3 fatty acids, particularly docosahexaenoic acid (DHA), have shown to exert beneficial effects on nonalcoholic fatty liver disease (NAFLD), which is characterized by the excessive accumulation of lipids and chronic injury in the liver. However, the effect of endogenous DHA biosynthesis on the lipid homeostasis of liver is poorly understood. In this study, we used a DHA biosynthesis-deficient zebrafish model, elovl2 mutant, to explore the effect of endogenously biosynthesized DHA on hepatic lipid homeostasis. We found the pathways of lipogenesis and lipid uptake were strongly activated, while the pathways of lipid oxidation and lipid transport were inhibited in the liver of elovl2 mutants, leading to lipid droplet accumulation in the mutant hepatocytes and NAFLD. Furthermore, the elovl2 mutant hepatocytes exhibited disrupted mitochondrial structure and function, activated endoplasmic reticulum (ER) stress, and hepatic injury. We further unveiled that the hepatic cell death and injury was mainly mediated by ferroptosis, rather than apoptosis, in elovl2 mutants. Elevating DHA content in elovl2 mutants, either through introduction of an omega-3 desaturase (fat1) transgene or feeding with a DHA-rich diet, could strongly alleviate NAFLD features and ferroptosis-mediated hepatic injury. Together, our study elucidates the essential role of endogenous DHA biosynthesis in maintaining hepatic lipid homeostasis and liver health, highlighting that DHA deficiency can lead to NAFLD and ferroptosis-mediated hepatic injury.

2.
Molecules ; 29(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38611772

RESUMO

Developing high-efficiency membrane materials for the rapid removal of organic dyes is crucial but remains a challenge. Polyoxometalates (POMs) clusters with anionic structures are promising candidates for the removal of cationic dyes via electrostatic interactions. However, their shortcomings, such as their solubility and inability to be mass-produced, hinder their application in water pollution treatment. Here, we propose a simple and green strategy utilizing the room temperature stirring method to mass produce nanoscale polyoxometalate-based metal-organic frameworks (POMOFs) with porous rhomboid-shaped dodecahedral and hexagonal prism structures. The products were labeled as POMOF1 (POMOF-PW12) and POMOF2 (POMOF-PMo12). Subsequently, a series of x wt% POMOF1/PAN (x = 0, 3, 5, and 10) nanofiber membranes (NFMs) were prepared using electrospinning technology, where polyacrylonitrile (PAN) acts as a "glue" molecule facilitating the bonding of POMOF1 nanoparticles. The as-prepared samples were comprehensively characterized and exhibited obvious water stability, as well as rapid selective adsorption filtration performance towards cationic dyes. The 5 wt% POMOF1/PAN NFM possessed the highest removal efficiency of 96.7% for RhB, 95.8% for MB, and 86.4% for CV dyes, which realized the selective separation over 95% of positively charged dyes from the mixed solution. The adsorption mechanism was explained using FT-IR, SEM, Zeta potential, and adsorption kinetics model, which proved that separation was determined via electrostatic interaction, hydrogen bonding, and π-π interactions. Moreover, the POMOF1/PAN membrane presented an outstanding recoverable and stable removal rate after four cycles. This study provides a new direction for the systematic design and manufacture of membrane separation materials with outstanding properties for contaminant removal.

3.
Zool Res ; 45(1): 176-188, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38199972

RESUMO

Omega-3 polyunsaturated fatty acids (n-3 PUFAs), particularly docosahexaenoic acid (22:6n-3, DHA), play crucial roles in the reproductive health of vertebrates, including humans. Nevertheless, the underlying mechanism related to this phenomenon remains largely unknown. In this study, we employed two zebrafish genetic models, i.e., elovl2 -/- mutant as an endogenous DHA-deficient model and fat1 (omega-3 desaturase encoding gene) transgenic zebrafish as an endogenous DHA-rich model, to investigate the effects of DHA on oocyte maturation and quality. Results show that the elovl2 -/- mutants had much lower fecundity and poorer oocyte quality than the wild-type controls, while the fat1 zebrafish had higher fecundity and better oocyte quality than wild-type controls. DHA deficiency in elovl2 -/- embryos led to defects in egg activation, poor microtubule stability, and reduced pregnenolone levels. Further study revealed that DHA promoted pregnenolone synthesis by enhancing transcription of cyp11a1, which encodes the cholesterol side-chain cleavage enzyme, thereby stabilizing microtubule assembly during oogenesis. In turn, the hypothalamic-pituitary-gonadal axis was enhanced by DHA. In conclusion, using two unique genetic models, our findings demonstrate that endogenously synthesized DHA promotes oocyte maturation and quality by promoting pregnenolone production via transcriptional regulation of cyp11a1.


Assuntos
Ácidos Docosa-Hexaenoicos , Peixe-Zebra , Animais , Humanos , Enzima de Clivagem da Cadeia Lateral do Colesterol , Oogênese/genética , Oócitos
4.
BMC Cancer ; 23(1): 1134, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993845

RESUMO

BACKGROUND: This study aimed to comprehensively evaluate the accuracy and effect of computed tomography (CT) and magnetic resonance imaging (MRI) based on artificial intelligence (AI) algorithms for predicting lymph node metastasis in breast cancer patients. METHODS: We systematically searched the PubMed, Embase and Cochrane Library databases for literature from inception to June 2023 using keywords that included 'artificial intelligence', 'CT,' 'MRI', 'breast cancer' and 'lymph nodes'. Studies that met the inclusion criteria were screened and their data were extracted for analysis. The main outcome measures included sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and area under the curve (AUC). RESULTS: A total of 16 studies were included in the final meta-analysis, covering 4,764 breast cancer patients. Among them, 11 studies used the manual algorithm MRI to calculate breast cancer risk, which had a sensitivity of 0.85 (95% confidence interval [CI] 0.79-0.90; p < 0.001; I2 = 75.3%), specificity of 0.81 (95% CI 0.66-0.83; p < 0.001; I2 = 0%), a positive likelihood ratio of 4.6 (95% CI 4.0-4.8), a negative likelihood ratio of 0.18 (95% CI 0.13-0.26) and a diagnostic odds ratio of 25 (95% CI 17-38). Five studies used manual algorithm CT to calculate breast cancer risk, which had a sensitivity of 0.88 (95% CI 0.79-0.94; p < 0.001; I2 = 87.0%), specificity of 0.80 (95% CI 0.69-0.88; p < 0.001; I2 = 91.8%), a positive likelihood ratio of 4.4 (95% CI 2.7-7.0), a negative likelihood ratio of 0.15 (95% CI 0.08-0.27) and a diagnostic odds ratio of 30 (95% CI 12-72). For MRI and CT, the AUC after study pooling was 0.85 (95% CI 0.82-0.88) and 0.91 (95% CI 0.88-0.93), respectively. CONCLUSION: Computed tomography and MRI images based on an AI algorithm have good diagnostic accuracy in predicting lymph node metastasis in breast cancer patients and have the potential for clinical application.


Assuntos
Inteligência Artificial , Neoplasias da Mama , Humanos , Feminino , Metástase Linfática/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X , Algoritmos , Sensibilidade e Especificidade
5.
Front Psychol ; 14: 1202518, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37794902

RESUMO

This paper investigates the ancillary factors judges consider when sentencing dangerous driving offenses. These factors are divided into favorable (i.e., "Confess" [CF], and "Actively compensate and obtain forgiveness from victims" [AC]) and unfavorable categories (i.e., "Mainly or solely responsible for the accident" [MSR], and "Post-accident behavior" [BAA]). Results indicate that both types of factors mediate the relationship between "Blood Alcohol Concentration" (BAC) and the sentencing outcome: favorable factors have a significant negative correlation with sentences, while unfavorable ones show a positive correlation. The mediation effect ratios are 13.8% and 19.1% respectively, with no significant differences between their impacts on judges' sentencing decisions.

6.
Environ Sci Pollut Res Int ; 30(46): 102586-102603, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37670090

RESUMO

Environmental pollution, especially agricultural carbon emissions (ACE), has led to public health problems to rural areas in China and accompanied by a heavy medical economic burden. However, most studies on carbon dioxide emissions and healthcare expenditures focused on the industrial sector, and the effect of ACE was overlooked. Therefore, studying the effect of ACE on rural residents' healthcare expenditures (NHCE) is not only conducive to accelerating the low-carbon transformation of agriculture but also has important implications for reducing healthcare expenditures. In addition, the effect of ACE on NHCE in different areas might be complex and nonlinear due to differences in years of schooling (EDU) leading to different awareness of environmental protection and health among farmers. Therefore, this paper used the Bayesian quantile regression (BQR) model and the panel threshold model to explore the effect of ACE on NHCE in different areas, based on the panel data of 31 provinces in China from 2007 to 2019. The results showed that ACE and NHCE experienced similar spatial distribution from 2007 to 2019. The BQR estimation results found that ACE had a significant positive effect on NHCE at different quantile levels during the sample period, public health concern, and thereby increasing the medical and economic burden of rural households. Meanwhile, ACE had a positive effect on NHCE with a significant single threshold effect from EDU. Specifically, farmers gradually realize the harm of environmental pollution to health with the continuous improvement of education level, and then ACE aggravated the improvement of NHCE after exceeding the threshold. EDU was more essential for farmers in contiguous poverty (CP) areas than in relatively developed (RD) areas and played an important role between ACE and NHCE. Furthermore, demographic structure, economic development, and public services were also positive driving factors for NHCE. The results of analysis provide a valuable reference for understanding the factors influencing NHCE and enable formulation of ACE emission reduction policies according to local conditions.


Assuntos
Fazendeiros , Gastos em Saúde , Humanos , Teorema de Bayes , Agricultura , Dióxido de Carbono/análise , Desenvolvimento Econômico , Escolaridade , China
7.
Int J Biol Sci ; 19(3): 981-993, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36778120

RESUMO

Although current cancer immunotherapies that target PD-1/PD-L1 immune checkpoint to reinvigorate exhausted T cells have achieved impressive clinical outcomes, only a small proportion of patients respond. New therapeutic targets are therefore needed to be identified to further unleash the anti-tumor potential of T cells and benefit more patients. Galectin-9 (Gal-9), initially identified as a ligand for TIM-3 to induce T cell death, acts as an immunosuppressive regulator in the tumor microenvironment (TME) but its potential as a therapeutic target remains largely elusive. Here we show that antibody neutralization of Gal-9, in combination with inhibition of Ataxia telangiectasia mutated (ATM), a kinase essential for DNA damage response (DDR), is a promising modality for cancer immunotherapy. Genetic depletion of ATM in tumors markedly potentiated anti-Gal-9 therapy in a syngeneic mouse model. Mechanistically, ATM inhibition greatly upregulated Gal-9 expression and secretion in a variety of human and murine tumor cells via the cGAS-STING-interferon ß (IFNß) innate immune pathway. Combination of Gal-9 inhibition with AZD1390, a selective ATM inhibitor currently evaluated in clinical trials, significantly suppressed tumor growth and prolonged survival in multiple syngeneic mouse models, including the poorly-immunogenic LLC lung tumors that do not respond to PD-1/PD-L1 blockade, concomitant with increased T cell infiltration. These results reveal Gal-9 induction via STING/IFNß signaling as an important mechanism mediating tumor immune escape that could be targeted for cancer immunotherapies, and unveil a novel anti-Gal-9-based combination strategy for cancer immunotherapies in a wide variety of malignancies, including those resistant to PD-1/PD-L1 blockade.


Assuntos
Ataxia Telangiectasia , Neoplasias Pulmonares , Humanos , Animais , Camundongos , Antígeno B7-H1/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Imunoterapia/métodos , Galectinas/metabolismo , Microambiente Tumoral , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo
8.
Sensors (Basel) ; 22(11)2022 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-35684748

RESUMO

To reduce the pain and the probability of cross-infection caused by the invasive blood glucose testing instruments, the ex vivo glucose measurement is of high significance. The electrical property of blood varies with the density of the glucose, which can be sensed by measuring its reflected coefficient in millimeter-wave. In this article, we built a contactless glucose solution concentration measurement system based on 77-GHz FMCW radar. Several preliminary signal processing algorithms are cascaded with a deep neural network to improve the accuracy of glucose solution concentration measurement. Our experiment shows that the resolution of this ex vivo glucose measurement can achieve up to 0.1 mg/mL.


Assuntos
Radar , Processamento de Sinais Assistido por Computador , Algoritmos , Glucose
9.
Proc Natl Acad Sci U S A ; 119(14): e2119194119, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35312339

RESUMO

SignificanceSulfur isotopes confirm a key role for atmospheric sulfur gases in climatic cooling, mass extinction, and the demise of dinosaurs and other global biota after the Chicxulub bolide impact at the Cretaceous-Paleogene boundary. The sulfur isotope anomalies are confined to beds containing ejecta and, in the immediately overlying sediments, are temporally unrelated to known episodes of volcanism that also bracket this event, further addressing the controversial role of the Deccan Traps in the extinction.


Assuntos
Dinossauros , Extinção Biológica , Animais , Isótopos , Enxofre
10.
Biomed Rep ; 16(2): 14, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35070298

RESUMO

The application of next-generation sequencing (NGS) in routine clinical analysis is still limited. The significance of NGS in the identification of pathogens of lower respiratory tract infection should be assessed as part of routine clinical bacterial examinations and chest imaging results. In the present study, the alveolar lavage fluid samples of 30 patients (25 males and 5 females, aged 19-92 years old, with a median age of 62) were examined by routine bacterial culture and NGS, and the results of pathogen detection and identification were compared. Chest imaging showed consolidation in all 30 patients (100%), and pleural effusion in 13 of the 30 patients (43.33%). The routine bacterial culture of the lavage solution was only positive in 14 of the 30 patients (46.6%), and negative in 16 patients (53.33%). However, the positive rate of NGS test results of the lavage fluid was 100%. A total of 12 cases (40%) were completely consistent with the routine bacterial culture test, with 56 other pathogens of mixed infection detected, accounting for the short comings of the routine bacterial examination. Although NGS cannot distinguish between live and dead bacteria, it is still a useful detection technology for accurate diagnosis of clinical infectious diseases. It is worthy of adaptation in the clinic for more effective clinical management and treatment of the lower respiratory airway infection in addition to the routine bacterial culture testing.

11.
Environ Sci Pollut Res Int ; 28(8): 9991-10004, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33159229

RESUMO

The development of low-carbon agriculture systems has been a global consensus to reduce carbon emissions in the agricultural sector for addressing climate change challenges. This fact brings the need to study the agricultural carbon emissions (ACEs). Studies focusing on calculating the spatiotemporal changes of ACEs and analyzing the main factors for ACE changes have been conducted. The agricultural technology inputs (ATIs) as an important factor to influence ACEs have been identified. The traditional linear model was the commonly used method to study the relationship between ATIs and ACEs, whereas the impact of ATIs on ACEs in different areas might be complex and nonlinear due to the differences in trade openness causing different development levels of agricultural technologies. Therefore, this study aims to investigate the effect of trade openness on the relationship between ATIs and ACEs using a panel threshold model and put forward policy implications for the low-carbon agriculture development. The analysis was based on data from a panel of 31 provinces of China during 2003-2018. The results show that ATIs and ACEs increased from 2003 to 2018 and the spatial distribution of ATIs was similar to that of ACEs. The ATIs had a positive effect on ACEs with a significant single-threshold effect from trade openness. When the trade openness was below the threshold (0.1425), the positive effect of ATIs on ACEs was significant (coefficient, 0.117), whereas, when the trade openness was above the threshold (0.1425), the positive effect of ATIs on ACEs significantly decreased (coefficient, 0.062). Furthermore, industrial structure and agricultural economic development were the positive drivers of ACEs, while trade openness, education level of rural workers, R&D funding, and natural disasters had negative relationships with ACEs. The results provide valuable references for understanding ACE drivers and developing low-carbon agriculture with the consideration of ATIs and trade openness.


Assuntos
Carbono , Desenvolvimento Econômico , Agricultura , Dióxido de Carbono/análise , China , Humanos , Tecnologia
12.
Front Pharmacol ; 11: 1287, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32973518

RESUMO

Eucalyptol (1,8-cineole), the major constituent of eucalyptus oil (EO), was used in traditional medicine as a remedy for colds and bronchitis. This study aimed at clarifying the effect of eucalyptol on respiratory immune function of CD8 and CD4 cells, and alveolar macrophages (AM). Thirty male Sprague-Dawley rats were divided into experimental and control groups. The drug was given once a day for 3 weeks and the experimental group was divided according to the eucalyptol dose into: 30, 100, and 300 mg·kg-1 groups. Flow cytometry was used to detect the phagocytic function of CD4, CD8 cells, and AM in the bronchopulmonary lavage fluid. The 30 and 100 mg·kg-1 groups had an up-regulation effect on CD8 (p < 0.05), with no significant effect on macrophage phagocytosis. The 300 mg·kg-1 group had an inhibitory effect on CD8 and macrophage phagocytosis (p < 0.05), with no significant difference in CD4 between groups. Further investigation was conducted to evaluate the effect of EO on immune function in rats by detecting blood T, B, and NK cells using flow cytometry, and blood IgA, IgG, IgM, and IFN-γ levels by ELISA. High dosage of eucalyptol significantly reduced the proportion of blood B and NK cells (p < 0.05). IgA was decreased in the 100 and 300 mg·kg-1 groups (p < 0.05). There are no significant differences between the number of T cells and the IgG, IgM, and IFN-γ levels between experimental and control groups. Rational use of EO containing eucalyptol can improve the immune function of the respiratory tract and the body immunity, while high dose could have damaging effects, through modifying the phagocytic function of CD8 cells and reducing the proportion of blood B cells, NK cells, and IgA.

13.
Mar Biotechnol (NY) ; 22(5): 613-619, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32880080

RESUMO

Teleost fish can synthesize one of the major omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFAs), docosahexaenoic acid (DHA, 22:6n-3), from dietary α-linolenic acid (ALA; 18:3n-3), via elongase of very long-chain fatty acid (Elovl) and fatty acid desaturase (Fads). However, it remains unclear which elongase is primarily responsible for the endogenous synthesis of DHA. Here, in this study, the knockout models of the two major elongases, Elovl2 and Elovl5, were generated by CRISPR/Cas9 approach in zebrafish and comparatively analyzed. The homozygous mutants were validated by Sanger sequencing, mutation-mediated PCR, and whole-mount in situ hybridization analysis of the endogenous target genes. Compared with wild-type (WT) counterparts, the content of DHA was significantly reduced by 67.1% (P < 0.05) in the adult liver and by 91.7% (P < 0.01) in the embryo at 3-day post-fertilization (dpf) of the elovl2 mutant, but not of the elovl5 mutant. Further study revealed that elovl2 and fads2 was upregulated by 9.9-fold (P < 0.01) and 9.7-fold (P < 0.01) in the elovl5 mutant, and elovl5 and fads2 were upregulated by 15.1-fold (P < 0.01) and 21.5-fold (P < 0.01) in the elovl2 mutant. Our study indicates that although both Elovl2 and Elovl5 have the elongase activity toward C20, the upregulation of elovl2 could completely replace the genetic depletion of elovl5, but upregulation of elovl5 could not compensate the endogenous deficiency of elovl2 in mediating DHA synthesis. In conclusion, the endogenous synthesis of DHA in is mediated by Elovl2 but not Elovl5 in zebrafish and a DHA-deficient genetic model of zebrafish has been generated.


Assuntos
Ácidos Docosa-Hexaenoicos/biossíntese , Ácidos Graxos Dessaturases/genética , Elongases de Ácidos Graxos/genética , Peixe-Zebra/metabolismo , Animais , Sistemas CRISPR-Cas , Ácidos Docosa-Hexaenoicos/genética , Embrião não Mamífero/metabolismo , Proteínas de Peixes/genética , Técnicas de Inativação de Genes , Fígado/metabolismo , Peixe-Zebra/genética
14.
Mar Biotechnol (NY) ; 21(2): 171-185, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30588551

RESUMO

Omega-3 polyunsaturated fatty acids (n-3 PUFAs), such as eicosapentaenoic acid (20:5n-3, EPA) and docosahexaenoic acid (22:6n-3, DHA), are essential for neural development and human health. The n-3 PUFAs are mainly obtained from marine fish by dietary intake. Freshwater fish species usually contain low level of n-3 PUFAs due to the lack of n-3 PUFAs in their food chain. In this study, we report on the substantial production of EPA and DHA in a globally important freshwater fish species, common carp (Cyprinus carpio). This was achieved by introducing an "all-fish" transgene CA:fat1 containing the fish codon-optimized omega-3 desaturase gene (fat1) driven by the common carp ß-actin promoter (CA). Through a sperm sample screening method, we successfully generated fat1-positive F1 transgenic population with high efficiency. In F1 population, the muscle contents of ALA (18:3n-3), EPA and DHA were significantly increased when compared with non-transgenic siblings. Thereafter, four independent F2 heterozygous lines were obtained from 4 F1 transgenic males and a detailed comparison of fatty acids profile and growth performance was carried out for these 4 lines. All fat1-transgenic common carps from 4 lines showed an evident decrease in n-6 PUFA contents and a substantial increase in n-3 PUFA contents, among which line 4 stands out, showing a statistically significant increase in all 4 types of n-3 PUFAs including ALA (4.4-fold increase, p < 0.001), EPA (4.8-fold increase, p < 0.01), C22:5n-3 (DPA, 2.4-fold increase, p < 0.05), and DHA (1.9-fold increase, p < 0.05). Therefore, the line 4 was selected as the optimized breeding stock for further study, and the proximate nutrition composition and PUFA synthesis pathway were analyzed. Our study demonstrates that in the transgenic group, the muscular lipid content did not change, while fat accumulations in the internal organs and especially in the liver were significantly decreased as a result of hyperactivation of fatty acid oxidation process. Finally, we conclude that the "all-fish" CA:fat1-transgenic freshwater fish-common carp-can serve as a novel healthy dietary source of n3-PUFAs, especially EPA and DHA.


Assuntos
Caderinas/genética , Carpas/genética , Ácidos Graxos Ômega-3/biossíntese , Valor Nutritivo , Animais , Animais Geneticamente Modificados , Ácido Eicosapentaenoico/análogos & derivados , Ácidos Graxos Ômega-3/análise , Ácidos Graxos Ômega-3/genética , Feminino , Técnicas de Transferência de Genes , Masculino
15.
Plant Cell ; 30(12): 3024-3037, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30538156

RESUMO

Response regulators play significant roles in controlling various biological processes; however, their roles in plant meiosis remain unclear. Here, we report the identification of OsRR24/LEPTOTENE1 (LEPTO1), a rice (Oryza sativa) type-B response regulator that participates in the establishment of key molecular and morphological features of chromosomes in leptotene, an early stage of prophase I in meiosis. Although meiosis initiates normally, as indicated by staining of the centromere-specific histone CENH3, the meiotic chromosomes in lepto1 mutant pollen mother cells fail to form the thin thread-like structures that are typical of leptotene chromosomes in wild-type pollen mother cells. Furthermore, lepto1 mutants fail to form chromosomal double-strand breaks, do not recruit meiosis-specific proteins to the meiotic chromosomes, and show disrupted callose deposition. LEPTO1 also is essential for programmed cell death in tapetal cells. LEPTO1 contains a conserved signal receiver domain (DDK) and a myb-like DNA binding domain at the N terminus. LEPTO1 interacts with two authentic histidine phosphotransfer (AHP) proteins, OsAHP1 and OsAHP2, via the DDK domain, and a phosphomimetic mutation of the DDK domain relieves its repression of LEPTO1 transactivation activity. Collectively, our results show that OsRR24/LEPTO1 plays a significant role in the leptotene phase of meiotic prophase I.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Meiose/genética , Proteínas Nucleares/metabolismo , Oryza/genética , Proteínas de Ciclo Celular/genética , Cromossomos de Plantas/genética , Meiose/fisiologia , Prófase Meiótica I/genética , Prófase Meiótica I/fisiologia , Proteínas Nucleares/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pólen/genética , Pólen/metabolismo
16.
Appl Opt ; 57(28): 8114-8118, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30461758

RESUMO

An optofluidic variable optical attenuator (VOA) is proposed in this paper, where the microfluidic driving technology adopts the electrically controlled way. The proposed driving technology solves some problems of existing microfluidic driving technologies and introduces a simple structure, a small volume, high precision, and a quick response for the VOA. This VOA has some advantages over other VOAs, such as a wide wavelength band (from visible light to the near infrared), a wide adjustable attenuation range, a low wavelength-dependent loss, and a quick response. The experiment results indicate that the attenuation range of this VOA is more than 80 dB and the wavelength-dependent loss is 0.09 dB at an attenuation of 20 dB in the C-band. Most VOAs have millisecond-scale response times, whereas the response time here is about 155-180 µs. Our work shows a new way to design miniaturized VOAs with good performance and can also promote optofluidics.

17.
Artigo em Inglês | MEDLINE | ID: mdl-24438297

RESUMO

In this study, we determined the complete nucleotide sequence of the mitochondrial genome for a cold water fish, Leuciscus idus. The complete mitochondrial genome was sequenced and analyzed using the primer walking method and 30 pairs of newly designed primers were used. Direct sequencing of the PCR products demonstrated that the genome contained the same 37 mitochondrial genes (two ribosomal RNA, 22 transfer RNA and 13 protein-coding genes) and two main non-coding regions (the control region and the origin of the light strand replication) as those found in other vertebrates. Nearly all the protein-coding genes' start codons were ATG except COX 1, meanwhile, the termination codons of which varied with TAA, TA, T, or TAG.


Assuntos
Cyprinidae/genética , Genoma Mitocondrial/genética , Análise de Sequência de DNA , Animais , Genes de RNAr , Anotação de Sequência Molecular , Dados de Sequência Molecular , Fases de Leitura Aberta/genética , RNA de Transferência/genética
18.
Artigo em Inglês | MEDLINE | ID: mdl-24548012

RESUMO

As reported, previous studies of Phoxinus phoxinus ujmonensis (Cypriniformes: Cyprinidae) have focused primarily on morphology and ecology. In this study, we cloned and sequenced the complete nucleotide sequence of the mitochondrial genome for P. phoxinus ujmonensis. The mitogenome was 17,738 bp in length, including 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and 1 control region. All genes were encoded on the heavy strain except for ND6 and eight tRNA genes. The overall base composition of the heavy strain was 28.50% for A, 28.24% for T, 25.32% for C and 17.94% for G. The control region was revealed to contain tandem repeats. The mitogenome data of P. phoxinus ujmonensis should contribute to phylogenetic analysis and studies of population genetics of Phoxinus fishes.


Assuntos
Cipriniformes/genética , Genoma Mitocondrial , Animais , Pareamento de Bases/genética , Sequência de Bases , DNA Mitocondrial/genética , Genes Mitocondriais , Fases de Leitura Aberta/genética
19.
Chemistry ; 21(9): 3671-81, 2015 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-25619819

RESUMO

A series of meta-substituted fatty acid octaester derivatives and their transition-metal complexes of meso- tetraphenyl porphyrins (TPP-8OOCR, with R = C(n-1)H(2n-1), n = 8, 12, or 16) have been prepared through very simple synthesis protocols. The thermotropic phase behavior and the liquid crystalline (LC) organization structures of the synthesized porphyrin derivatives were systematically investigated by a combination of differential scanning calorimetry (DSC), polarized optical microscopy (POM), and variable-temperature small-angle X-ray scattering/wide-angle X-ray scattering (SAXS/WAXS) techniques. The shorter octanoic acid ester substituted porphyrin (C8-TPP) did not show liquid crystallinity and its metal porphyrins exhibited an uncommon columnar mesophase. The lauric acid octaester (C12-TPP) and the palmitic acid octaester (C16-TPP) series porphyrins generated hexagonal columnar mesophase Colh. Moreover, the metal porphyrins C12-TPPM and C16-TPPM with M = Zn, Cu, or Ni, exhibited well-organized Colh mesophases of broad LC temperature ranges increasing in the order of TPPNi

Assuntos
Complexos de Coordenação/síntese química , Ácidos Graxos/química , Ácidos Láuricos/química , Metais/química , Ácido Palmítico/química , Porfirinas/química , Elementos de Transição/química , Complexos de Coordenação/química , Ésteres , Estrutura Molecular , Difração de Raios X
20.
Mitochondrial DNA ; 26(5): 751-2, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24460156

RESUMO

The complete mitochondrial genome of Leuciscus leuciscus baicalensis was cloned and sequenced in the present study. The genome which had a mostly conserved structural organization in comparison with that of other teleost fish was 16,606 bp in size. It consisted of 37 genes (13 protein-coding genes, 22 transfer RNA genes and 2 ribosomal RNA genes), and 2 main non-coding regions (the control region and the origin of the light strand replication). All protein-coding genes started with ATG except for COX 1, which began with GTG. However, the termination codons of 13 protein-coding genes varied with TAA, TA, T or TAG. The complete mitochondrial genome sequence provided useful information for phylogenetic analysis and studies of population genetics of L. leuciscus baicalensis.


Assuntos
Cipriniformes/genética , Genética Populacional , Genoma Mitocondrial , Genômica , Animais , Códon , Genes Mitocondriais , Genômica/métodos , Fases de Leitura Aberta
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