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1.
Food Chem ; 305: 125502, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31606692

RESUMO

Melatonin, a tryptophan derivative, is an important functional component in grape berries. We investigated the effect of cluster bagging on melatonin biosynthesis in the berries of two wine grape cultivars, Cabernet Sauvignon and Carignan, during fruit development and ripening. Cluster bagging delayed fruit coloring and ripening, and bag-treated berries of both grape cultivars synthesized more melatonin and most of the precursor compounds including L-tryptophan, N-acetylserotonin, tryptamine, and serotonin compared to those exposed to light (control) conditions. Interestingly, 5-methoxytryptamine was only detected in the berries of Carignan and not of Cabernet Sauvignon, both in the cluster bagging and control groups. In addition, melatonin and most of its precursors, decreased after veraison. VvSNAT1 and VvT5H expression levels were positively correlated with melatonin content. Our findings suggested that melatonin synthesis pathways differ among grape cultivars, and that VvSNAT1 and VvT5H may show key regulatory roles in the melatonin synthesis of grape berries.


Assuntos
Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Melatonina/biossíntese , Vitis/crescimento & desenvolvimento , Vitis/metabolismo , Vinho
2.
Opt Express ; 27(19): 27039-27045, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31674572

RESUMO

In this paper, a nematic liquid crystal (NLC)-based tunable terahertz (THz) plasmonic metamaterials (MMs) with large modulation depth (MD) and low insertion loss (IL) is designed and experimentally verified at THz frequencies. The proposed structure includes two-layered MM that is immersed in LC. The metal MM is used directly as electrode. The tunable device with a 46×46 array of sub-wavelength circular air loops was fabricated on a quartz glass substrate, with 2×2 cm2 area and 220 µm thickness. The obtained results show that the amplitude MD and IL for normally incident electromagnetic (EM) waves are about 96% and 1.19 dB at 421.2 GHz, respectively, when the bias voltage applied to the NLC layer varies from 0 to 16 V. Meanwhile, the transmission peak frequency gradually decreases from 421.2 to 381.8 GHz, and the frequency tunability (FT) of the proposed structure is greater than 9.35%. This study provides a potential solution for THz modulators, filters, and switches.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31425057

RESUMO

In recent times, sequence-to-sequence (seq2seq) models have gained a lot of popularity and provide state-of-the-art performance in a wide variety of tasks, such as machine translation, headline generation, text summarization, speech-to-text conversion, and image caption generation. The underlying framework for all these models is usually a deep neural network comprising an encoder and a decoder. Although simple encoder--decoder models produce competitive results, many researchers have proposed additional improvements over these seq2seq models, e.g., using an attention-based model over the input, pointer-generation models, and self-attention models. However, such seq2seq models suffer from two common problems: 1) exposure bias and 2) inconsistency between train/test measurement. Recently, a~completely novel point of view has emerged in addressing these two problems in seq2seq models, leveraging methods from reinforcement learning (RL). In this survey, we~consider seq2seq problems from the RL point of view and provide a formulation combining the power of RL methods in decision-making with seq2seq models that enable remembering long-term memories. We present some of the most recent frameworks that combine the concepts from RL and deep neural networks. Our work aims to provide insights into some of the problems that inherently arise with current approaches and how we can address them with better RL models. We also provide the source code for implementing most of the RL models discussed in this paper to support the complex task of abstractive text summarization and provide some targeted experiments for these RL models, both in terms of performance and training~time.

5.
Mar Pollut Bull ; 146: 591-597, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31426197

RESUMO

A molecularly imprinted polymer (MIP) anchored on the surface of CdTe quantum dots (QDs) was fabricated and used as a fluorescent probe for sulfadiazine (SDZ) detection in seawater. CdTe QDs was used as photoluminescent material, SDZ as the template, 3-aminopropyltriethoxysilane (APTES) as the functional monomer and tetraethyl orthosilicate (TEOS) as the cross-linking agent. Characterizations of MIP-QDs were analyzed by Fourier transform infrared (FT-IR), Transmission electron microscopy (TEM) and Scanning electron microscope (SEM). The conditions were optimized for the detection of MIP-QDs to SDZ. The mechanism of fluorescence quenching was studied by UV-Vis absorption spectroscopy and fluorescence spectroscopy. Under optimal conditions, the fluorescence intensity of MIP-QDs decreased linearly between 4- and 20 µM SDZ with a good correlation coefficient of 0.995. The limit of detection is 0.67 µM and the recovery is between 91.8 and 109.4% with RSD lower than 3.9%. These results indicated that MIP-QDs for SDZ detection in seawater was developed successfully.


Assuntos
Compostos de Cádmio/química , Pontos Quânticos/química , Água do Mar/análise , Sulfadiazina/análise , Telúrio/química , Poluentes Químicos da Água/análise , Antibacterianos/análise , Corantes Fluorescentes/química , Limite de Detecção , Microscopia Eletrônica de Transmissão , Impressão Molecular/métodos , Polímeros/síntese química , Polímeros/química , Propilaminas/química , Silanos/química , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Chin Med J (Engl) ; 132(17): 2059-2065, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31436597

RESUMO

BACKGROUND: The pathogenesis of obstructive sleep apnea (OSA) remains not fully understood. This study aimed to explore the mechanism of OSA by assessing the association between the human tandem of P domains in a weak inwardly rectifying K channel (TWIK)-related acid-sensitive K channel-1 (TASK-1) gene and OSA. METHODS: A total of 164 patients with severe OSA and 171 patients without OSA were recruited from the Center for Hypertension of People's Hospital of Xinjiang Uygur Autonomous Region (China) from April to December in 2016. Two single nucleotide polymorphisms (rs1275988 and rs2586886) in the TASK-1 gene were selected and genotyped using a kompetitive allele specific polymerase chain reaction genotyping system. Clinical-pathological characteristics and genotype data were compared between the severe and non-OSA groups to explore the association between TASK-1 gene polymorphism and severe OSA. RESULTS: There were no significant differences in genotype distribution, allele frequency, and the recessive and dominant model of the two selected single nucleotide polymorphisms (rs1275988 and rs2586886) between the severe and non-OSA groups in the total population (P > 0.05). However, for patients with a body mass index (BMI) ≥28 kg/m, the distribution of genotypes and alleles, and the recessive model (GG + GA vs. AA) exhibited significant differences between the severe and non-OSA group (for genotypes: P = 0.014 and P = 0.026; for alleles: P = 0.006 and P = 0.011; for the recessive model: P = 0.005 and P = 0.009, respectively). The simple logistic regression analysis revealed that the GG genotype was a risk factor for OSA. The odds ratio (OR) and 95% confidence intervals (CI) were 4.902 (1.582-15.186, P = 0.006) for rs1275988 and 4.420 (1.422-13.734, P = 0.010) for rs2586886, respectively. In multivariate logistic regression analysis, the combination of GG genotypes of rs1275988 with BMI ≥28 kg/m increased the risk of severe OSA (OR = 8.916, 95% CI 4.506-17.645, P < 0.001). CONCLUSION: Both the GG genotype of rs1275988 and GG genotype of rs2586886 in the TASK-1 gene may play as potential risk factors in obese patients with OSA.

7.
Medicine (Baltimore) ; 98(32): e15837, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31393341

RESUMO

Peripherally inserted central catheters (PICCs) can provide nutritional and medical support for very low birth weight or critically ill newborns. The aim of this study was to retrospectively analyze the use of PICCs in our clinic for critically ill newborns to evaluate the relationship between catheter related factors and the occurrence of complications.Retrospective analysis was conducted for all newborns consecutively admitted at the Neonatal Intensive Care Unit (NICU), Chongqing Health Center for Women and Children, who underwent PICC insertion between May 2011 and March 2018. Data collected included total puncture success rate, one puncture success rate, infection rate, complication rate, unplanned catheter withdrawal rate, device days, and catheter indwelling time.Five-hundred eighty-eight infants (304 males and 284 females) aged 3.4 ±â€Š3.9 days, mean gestational age of 30.9 ±â€Š2.7 weeks and a mean body mass of 1.38 ±â€Š0.47 kg at insertion were included. Total puncture success rate was 99.65%, one puncture success rate was 77.77%. The mean catheter retention was 13.6 ±â€Š6.7 days: more than 30 days in 15 (2.61%) cases, 20 to 30 days in 60 (10.43%) cases, 10 to 19 days in 372 (64.70%) cases, and 62 days in 1 case. Complications occurred in 63 (10.71%) cases: with PICC insertion within 24 hours after birth in 29 (15.43%), within 48 hours in 13 (6.63%), and after 48 hours in 21 (10.99%) cases. Catheter tip culture was positive in 3 cases and there was 1 case of catheter-related bloodstream infection.Nursing measures of the maintenance of body temperature and the evaluation of blood vessels were important conditions for improving the success rate of one puncture in critically ill neonates. PICC catheterization as early as 48 hours will not increase the difficulty of PICC puncture. Nor did it increase the incidence of PICC complications.


Assuntos
Cateterismo Periférico/estatística & dados numéricos , Cateteres de Demora/estatística & dados numéricos , Estado Terminal , Unidades de Terapia Intensiva Neonatal/estatística & dados numéricos , Infecções Relacionadas a Cateter/epidemiologia , Infecções Relacionadas a Cateter/prevenção & controle , Cateteres de Demora/efeitos adversos , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido de muito Baixo Peso , Masculino , Estudos Retrospectivos
8.
Materials (Basel) ; 12(11)2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31159407

RESUMO

The large diameter metal shell component (LDMSC) is an important part of gas insulated (metal-enclosed) switchgear (GIS). The LDMSC with multi branches is filled with gas under certain pressure. The plastic forming process is an efficient approach to manufacturing the high reliability LDMSC. The warm flanging process has been widely used to form LDMSC using aluminum alloy. The forming process is characterized by local heating, and the distribution of temperature is strongly inhomogeneous. Although the wall thickness of the shell is 10 mm to 20 mm, the ratio of outer diameter to thickness is more than 40. These present some difficulties in the flanging process and result in some forming defects. Detailed forming characteristics are hard to obtain by analytical and experimental methods. Thus, the through-process finite element (FE) modeling considering heating, forming, unloading, and cooling is one of the key problems to research the manufacturing process of LDMSC. In this study, the through-process FE modeling of the warm flanging process of LDMSC using aluminum alloy was carried out based on the FORGE. The thermo-mechanical coupled finite element method was adopted in the modeling, and the deformation of the workpiece and the die stress were considered together in the modeling. A full three-dimensional (3D) geometry was modeled due to inhomogeneous distribution in all directions for the temperature field. The simulation data of local flame heating could be transferred seamlessly to the simulations of the deforming process, the unloading process, and the cooling process in the through-process FE model. The model was validated by comparison with geometric shapes and forming defects obtained from the experiment. The developed FE model could describe the inhomogeneous temperature field along circumferential, radial, and axial directions for the formed branch as well as the deformation characteristic and the unloading behavior during the warm flanging process. By using the FE model, the forming defects during the flanging process and their controlling characteristics were explored, the evolution of the temperature field through the whole process was studied, and deformation and springback characteristics were analyzed. The results of this study provide a basis for investigating deformation mechanisms, optimizing processes, and determining parameters in the warm flanging process of a large-diameter aluminum alloy shell component.

9.
J Thorac Dis ; 11(4): 1580-1588, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31179102

RESUMO

Background: To describe the clinical manifestations, immunological features, treatments, and outcomes of patients with thymic epithelial tumor (TET) complicated by immunological abnormalities, and to improve knowledge on immunological abnormalities in this rare disease. Methods: Patients with pathologically confirmed TET at Beijing Chaoyang Hospital between January 2013 and May 2018 were included in this study, and clinical data were analyzed retrospectively. Immunological abnormalities were classified into two groups as follows: Good syndrome (GS) and autoimmune disease (AD). Results: Fifty-nine TET patients were enrolled; twenty-two patients (37.3%) had immune dysfunction. There were no gender, age, or histological type differences between groups with or without immunological abnormalities. Six patients had GS, of whom four patients were diagnosed after thymectomy. Recurrent respiratory infections, particularly opportunistic infections, were the most common manifestation. Three GS patients developed a second cancer (50%; P=0.011). Anti-infective therapy and immunoglobulin supplements effectively treated GS. Seventeen patients developed ADs, including myasthenia gravis (MG) (n=13), Hashimoto's thyroiditis (n=4), Sjogren's syndrome (n=1), rheumatoid arthritis (n=1), pemphigus (n=1), and Evans syndrome (n=1). One patient developed both MG and GS and 4 patients presented with two ADs. Three AD cases occurred after thymectomy. Pemphigus and 80% (8/10) of MG cases were resolved following thymectomy. Conclusions: There is a strong association between immunological abnormalities and TET, which may present at any time point during the disease, even after thymectomy. In addition to infection, GS patients are more likely to develop a second cancer. Thymectomy may produce favorable outcomes for MG in this study, while surgery does not improve immunodeficiency in GS patients.

10.
Mikrochim Acta ; 186(6): 362, 2019 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-31104121

RESUMO

A fluorescent nanoprobe consisting of CdTe quantum dots (QDs) and coated with molecularly imprinted layers was prepared and successfully applied to the determination of norfloxacin (NOR) in seawater and wastewater samples. The 3-mercaptopropionic acid capped QDs were prepared and then covered with a protective silica shell. A molecularly imprinted layer was finally synthesized around the silanized QDs using 3-aminopropyltriethoxysilane as functional monomer and norfloxacin as the template. Compared with the non-imprinted polymer, the fluorescence of the nanoprobe with imprinted polymer (measured at excitation/emission wavelengths of 300/596 nm) is strongly reduced in the presence of NOR, and the imprinting factor is 8.8. Under the optimal experimental conditions, the detection limit of the nanoprobe is 0.18 µM, and response is linear between 0.5 - 28 µM of NOR. The relative standard deviation of the detection of NOR is <7.2%. In order to evaluate the practicality of the probe, wastewater and seawater samples spiked with norfloxacin were analyzed by this method, and recoveries ranged from 96.2 - 106.0%. Graphical abstract Schematic presentation and fluorescence spectrum of fluorescent nanoprobe with selectivity for norfloxacin (NOR). CdTe quantum dots (QDs) are used as fluorescent carriers, 3-aminopropyltriethoxysilane (APTES) as template molecules, tetraethyl orthosilicate (TEOS) as crosslinking agent, and aqueous ammonia as initiator.

11.
Zhongguo Zhong Yao Za Zhi ; 44(8): 1558-1563, 2019 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-31090319

RESUMO

Commonly used dosage forms of fermented Cordyceps powder products are capsules and tablets. The hygroscopicity of the powder,as one of the important parameters in the tableting process,has important effects on the tabletting process of the tablets. How to improve the hygroscopicity of powder is of great significance for the development of new composite particles. Therefore,particle design technology was used in this study to prepare composite particle powder,and its hygroscopicity was compared with fermented Cordyceps powder and physically mixed powder. By preparing three different types of powders,the equilibrium moisture absorption,particle size,scanning electron micrograph,angle of repose,contact angle and compression degree were compared to observe the effect of traditional Chinese medicine particle design technology on improving the hygroscopicity of the fermented Cordyceps powder. The results showed that the equilibrium moisture absorption was 21. 2%,19. 6%,14. 5% respectively for the fermented Cordyceps powder,physically mixed powder and composite particle powder; the median diameter was(49. 751± 0. 280),(59. 183± 0. 170),(12. 842±0. 080) µm,respectively; the mode diameter was(185. 479±1. 372),(173. 964± 1. 104),(61. 671± 0. 979) µm,respectively. In the scanning electron micrograph of the composite particle powder,it can be clearly seen that the fermented Cordyceps powder had hydrophobic gas phase nano-silica with a fixed shape and uniform size. The angle of repose was(50. 63 ± 0. 75) °,(49. 25 ± 0. 43) °,(48. 33±0. 84) ° respectively; the contact angle was(7. 4±0. 2) °,(8. 2±0. 3) °,(15. 0±2. 6) ° respectively; and the compression degree was(38. 2±1. 3) %,(35. 8±0. 2) %,(32. 5±2. 6) % respectively. This study showed that after treatment by the vibrating ultrafine pulverizer,the fermented Cordyceps powder particles had obvious and uniform small particle hydrophobic gas phase nano-silica adhered to form a partially wrapped coating structure,which reduced the contact surface of fermented Cordyceps powder with the outside world,thereby reducing the hygroscopicity of the composite particle powder. It further demonstrated that the hygroscopicity of fermented Cordyceps powder can be improved by particle design.


Assuntos
Cordyceps , Fermentação , Medicina Tradicional Chinesa , Molhabilidade , Tamanho da Partícula , Pós
12.
Appl Microbiol Biotechnol ; 103(11): 4313-4324, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31016357

RESUMO

In recent years, eukaryotic microorganisms have been widely applied to offer many solutions for everyday life and have come to play important roles in agriculture, food, health care, and the fine-chemicals industry. However, the complex genetic background and low homologous recombination efficiency have hampered the implementation of large-scale and high-throughput gene editing in many eukaryotic microorganisms. The low efficiency of homologous recombination (HR) not only makes the modification process labor-intensive but also completely precludes the application of many otherwise very useful genome editing techniques. Thus, increasing the efficiency of HR is clearly an enabling technology for basic research and gene editing in eukaryotic microorganisms. In this review, we summarize the current strategies for enhancing the efficiency of HR in eukaryotic microorganisms (particularly yeasts and filamentous fungi), list some small molecules and candidate genes associated with homologous and non-homologous recombination, and briefly discuss the further development prospects of these strategies.


Assuntos
Fungos/genética , Edição de Genes/métodos , Recombinação Homóloga , Engenharia Metabólica/métodos , Leveduras/genética
13.
Chin Med Sci J ; 34(1): 24-32, 2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30961777

RESUMO

Objective To explore the ability of texture analysis of gadoxetic acid-enhanced magnetic resonance imaging (MRI) T1 mapping images, as well as T1-weighted (T1W), T2-weighted (T2W) and apparent diffusion coefficient (ADC) maps for distinguishing between varying degrees of hepatic fibrosis in an experimental rat model.Methods Liver fibrosis in rats was induced by carbon tetrachloride intraperitoneal injection for 4-12 weeks (n=30). In the control group (n=10) normal saline was applied. The MRI protocol contained T2W, diffusion weighted imaging, pre-and post-contrast image series of T1W and T1 mapping images. METAVIR score was used to grade liver fibrosis as normal (F0), mild fibrosis (F1-2), and advanced fibrosis (F3-4). Texture parameters including mean gray-level intensity (Mean), standard deviation (SD), Entropy, mean of positive pixels (MPP), Skewness, and Kurtosis were obtained. Nonparametric Mann-Whitney U test was used to compare the average value of each texture parameter in each sequence for assessing the difference between F0 and F≥1 as well as F0-2 and F3-4. Receiver operating characteristic (ROC) curves were obtained to assess the diagnosing accuracy of the parameters for differentiating no liver fibrosis from liver fibrosis and rats with liver fibrosis grading F0-2 from those with grading F3-4. The area under ROC curve (AUC) was calculated to evaluate the diagnostic efficiency of texture parameters.Results Finally, 20 rats completed MR T1 mapping image scan. The pathologic staging of these 20 rats was no fibrosis (F0, n=6), mild fibrosis (F1-2, n=5) and advanced fibrosis (F3-4, n=9). On pre-contrast T1 mapping image, Entropy was seen to be statistically significant higher in the F≥1 group than that in the F0 group at each spatial scaling factor (SSF) setting (P=0.015, 0.015, 0.015, 0.013, 0.015 and 0.018 respectively to SSF=0, 2, 3, 4, 5, 6), and Mean of the F≥1 rats was statistically significant higher than that of the F0 rats at SSF 4, 5, 6 (P=0.004, 0.006, and 0.013, respectively). Entropy and Mean showed a moderate diagnostic performance in most SSF settings of T1 mapping pre-contrast images for differentiation of normal liver from liver fibrosis.Conclusions Certain texture features of gadoxetic acid-enhanced MR images, especially the Entropy of non-contrast T1 mapping image, was found to be a useful biomarker for the diagnosis of liver fibrosis.


Assuntos
Meios de Contraste/farmacologia , Imagem de Difusão por Ressonância Magnética , Gadolínio DTPA/farmacologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/fisiopatologia , Animais , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley
14.
Eur J Med Chem ; 171: 209-220, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30925337

RESUMO

The enzyme FabH catalyzes the initial step of fatty acid biosynthesis that is essential for bacterial survival. Therefore, FabH has been identified as an attractive target for the development of new antibacterial agents. We present here the discovery of a promising new series of Pyrazol-Benzimidazole amides with low toxicity and potent FabH inhibitory. Twenty-seven novel compounds have been synthesized, and all the compounds were characterized by 1H NMR, 13C NMR and MS. Afterwards they were evaluated for in-vitro antibacterial activities against E. coli, P. aeruginosa, B. subtilis and S. aureus, along with E. coli FabH inhibition and cytotoxicity test. Some compounds proved to be of low toxicity and potent, especially compound 31 exhibited the most potential to be a new drug with MIC of 0.49-0.98 µg/mL against the tested bacterial strains and IC50 of 1.22 µM against E. coli FabH. Eight analogues 16, 28, 30, 31, 33, 34, 35 and 36 with low range MIC against wild type Xanthomonas Campestris exhibited no inhibition against FabH-deficient mutant strain, which firmly proved the class of compounds arrived at antibacterial activity via interacting with FabH. In silico ADMET (Absorption, Distribution, Metabolism, Excretion and Toxicity) evaluation also pointed out that these compounds are potential for druggability. Further, effective overall docking scores of all the compounds have been recorded, and docking simulation of compound 31 into E. coli FabH binding pocket has been conducted, where solid binding interactions has been identified.


Assuntos
Bacillus subtilis/enzimologia , Inibidores Enzimáticos/farmacologia , Escherichia coli/enzimologia , Ácido Graxo Sintase Tipo II/antagonistas & inibidores , Pseudomonas aeruginosa/enzimologia , Staphylococcus aureus/enzimologia , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Descoberta de Drogas , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Ácido Graxo Sintase Tipo II/genética , Ácido Graxo Sintase Tipo II/metabolismo , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade
15.
Medicine (Baltimore) ; 98(8): e14283, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30813130

RESUMO

Although published studies have reported the association between MTHFR C677T (rs 1801133), A1298C (rs 1801131), and MTRR A66G (rs1801394) polymorphisms and male infertility in Asian populations, the results are conflicting. In order to accurately evaluate the relevance, a meta-analysis was performed.We searched for potential studies in 4 databases, containing PubMed, ScienceDirect, China National Knowledge Infrastructure (CNKI), and Wanfang database until May 31, 2018. The summarized odds ratio (OR) with 95% confidence intervals (95% CI) were calculated to evaluate the relevance in 5 genetic models. The heterogeneity test, sensitivity analysis, and publication bias test was performed by Review Manager 5.3 software.Overall, 22 case-control studies with 5049 cases and 4157 controls were included in this meta-analysis, which contained 20 studies of MTHFR C677T polymorphism, 12 studies of MTHFR A1298C polymorphism and 4 studies of MTRR A66G polymorphism. The results indicated that MTHFR C677T, A1298C, and MTRR A66G polymorphisms were significantly associated with male infertility in Asian populations (Dominant model: MTHFR CC + CT vs TT: OR = 0.60, 95% CI (0.53, 0.67), P <.00001; MTHFR AA + AC vs CC: OR = 0.62, 95% CI (0.49, 0.79), P = .0001; MTRR AA + AG vs GG: OR = 0.60, 95% CI (0.45, 0.81), P = .001. Recessive model: MTHFR CC vs CT + TT: OR = 0.67, 95% CI (0.61, 0.74), P <.00001; MTHFR AA vs AC + CC: OR = 0.79, 95% CI (0.70, 0.88), P <.0001; MTRR AA vs AG + GG: OR = 0.70, 95% CI (0.56, 0.88), P = .002. Heterozygote model: MTHFR CC vs CT: OR = 0.74, 95% CI (0.67, 0.82), P <.00001; MTHFR AA vs AC: OR = 0.83, 95% CI (0.73, 0.93), P = .002; MTRR AA vs AG: OR = 0.76, 95% CI (0.60, 0.92), P = .02. Homozygote model: MTHFR CC vs TT: OR = 0.48, 95% CI (0.41, 0.56), P <.00001; MTHFR AA vs CC: OR = 0.61, 95% CI (0.39, 0.93), P = .02; MTRR AA vs GG: OR = 0.51, 95% CI (0.36, 0.72), P = .0001. Allele model: MTHFR C vs T: OR = 0.70, 95% CI (0.66, 0.75), P <.00001; MTHFR A vsC: OR = 0.82, 95% CI (0.71, 0.95), P = .01; MTRR A vs G: OR = 0.76, 95% CI (0.66, 0.88), P = .00003). Stratified analyses by geographical location and source of controls showed the same results. Sensitivity analyses indicated that the final consequences of this meta-analysis were stable, and the publication biases test had not found obvious asymmetry.This meta-analysis indicates that MTHFR C677T, A1298C, and MTRR A66G polymorphisms are the risk factors with susceptibility to male infertility in Asians.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Ferredoxina-NADP Redutase/genética , Predisposição Genética para Doença , Infertilidade Masculina/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único , China , Humanos , Masculino , Fatores de Risco
16.
Yi Chuan ; 41(3): 193-205, 2019 Mar 20.
Artigo em Chinês | MEDLINE | ID: mdl-30872256

RESUMO

RNA is a polymeric molecule which is involved in various biological processes including the coding, decoding, regulation, and expression of genes. Whole transcriptome sequencing is the dominant method for studying RNA functions which assists researchers to deepen the exploration and analysis of gene structure and function and to reveal intrinsic links between gene expression and life phenomena. To date, extensive research has been done in animal husbandry models including swine and poultry by using high-throughput RNA sequencing technology. These studies included transcript structure, gene expression level and non-coding region function. In this review, we briefly introduce the general processes and strategies of RNA-seq and small RNA-seq technologies, and summarize the various achievements of the application of whole transcriptomics in animal husbandry.


Assuntos
Criação de Animais Domésticos , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Transcriptoma , Animais , Cruzamento , Aves Domésticas , Análise de Sequência de RNA , Suínos
17.
Appl Microbiol Biotechnol ; 103(8): 3239-3248, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30877356

RESUMO

Microalgae are arguably the most abundant single-celled eukaryotes and are widely distributed in oceans and freshwater lakes. Moreover, microalgae are widely used in biotechnology to produce bioenergy and high-value products such as polyunsaturated fatty acids (PUFAs), bioactive peptides, proteins, antioxidants and so on. In general, genetic editing techniques were adapted to increase the production of microalgal metabolites. The main genome editing tools available today include zinc finger nucleases (ZFNs), transcriptional activator-like effector nucleases (TALENs), and the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas nuclease system. Due to its high genome editing efficiency, the CRISPR/Cas system is emerging as the most important genome editing method. In this review, we summarized the available literature on the application of CRISPR/Cas in microalgal genetic engineering, including transformation methods, strategies for the expression of Cas9 and sgRNA, the CRISPR/Cas9-mediated gene knock-in/knock-out strategies, and CRISPR interference expression modification strategies.


Assuntos
Sistemas CRISPR-Cas/genética , Edição de Genes , Microalgas/genética , Proteína 9 Associada à CRISPR/genética , Regulação da Expressão Gênica , Marcação de Genes , Engenharia Genética , RNA Guia/genética , Transformação Genética
18.
Bioresour Technol ; 281: 449-456, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30846235

RESUMO

Terpenoids are a large class of natural compounds based on the C5 isoprene unit, with many biological effects such activity against cancer and allergies, while some also have an agreeable aroma. Consequently, they have received extensive attention in the food, pharmaceutical and cosmetic fields. With the identification and analysis of the underlying natural product synthesis pathways, current microbial-based metabolic engineering approaches have yielded new strategies for the production of highly valuable terpenoids. Yarrowia lipolytica is a non-conventional oleaginous yeast that is rapidly emerging as a valuable host for the production of terpenoids due to its own endogenous mevalonate pathway and high oil production capacity. This review aims to summarize the status and strategies of metabolic engineering for the heterologous synthesis of terpenoids in Y. lipolytica in recent years and proposes new methods aiming towards further improvement of terpenoid production.


Assuntos
Engenharia Metabólica/métodos , Terpenos/metabolismo , Yarrowia/metabolismo , Produtos Biológicos/metabolismo
19.
ACS Synth Biol ; 8(2): 445-454, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30616338

RESUMO

The filamentous fungus Fusarium fujikuroi is well-known for its production of natural plant growth hormones: a series of gibberellic acids (GAs). Some GAs, including GA1, GA3, GA4, and GA7, are biologically active and have been widely applied in agriculture. However, the low efficiency of traditional genetic tools limits the further research toward making this fungus more efficient and able to produce tailor-made GAs. Here, we established an efficient CRISPR/Cas9-based genome editing tool for F. fujikuroi. First, we compared three different nuclear localization signals (NLS) and selected an efficient NLS from histone H2B (HTBNLS) to enable the import of the Cas9 protein into the fungal nucleus. Then, different sgRNA expression strategies, both in vitro and different promoter-based in vivo strategies, were explored. The promoters of the U6 small nuclear RNA and 5S rRNA, which were identified in F. fujikuroi, had the highest editing efficiency. The 5S rRNA-promoter-driven genome editing efficiency reached up to 79.2%. What's more, multigene editing was also explored and showed good results. Finally, we used the developed genome editing tool to engineer the metabolic pathways responsible for the accumulation of a series GAs in the filamentous fungus F. fujikuroi, and successfully changed its GA product profile, from GA3 to tailor-made GA4 and GA7 mixtures. Since these mixtures are more efficient for agricultural use, especially for fruit growth, the developed strains will greatly improve industrial GA production.


Assuntos
Sistemas CRISPR-Cas/genética , Fungos/genética , Fungos/metabolismo , Fusarium/genética , Fusarium/metabolismo , Giberelinas/metabolismo , Edição de Genes/métodos , Genoma Fúngico/genética
20.
Mater Sci Eng C Mater Biol Appl ; 96: 635-641, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30606575

RESUMO

Cisplatin is a highly effective antitumor drug, which can kill cancer cells by crossing-linking DNA and inhibiting transcription, but this process is limited by the combination of cisplatin and many endogenous nucleophiles, such as glutathione (GSH). Thus, when cisplatin enter cells, it is potentially vulnerable to cytoplasmic inactivation by GSH. To settle this bottleneck, we designed and synthesized a probe compound (Probe 1) and fabricated pH-responsed cisplatin, Probe 1-loaded lipid-polymer hybrid NanoParticles (CPNPs) using a single-step sonication method. Probe 1 can specifically bind to GSH, thus avoiding the combination of GSH and cisplatin, and enhancing the pharmacological activity of cisplatin. In vitro studies have suggested CPNPs, compared with cisplatin, loaded lipid-polymer hybrid NanoParticles CNPs (Not contain Probe 1), could efficiently kill MCF-7 human breast cancer cells and A549 human nonsmall lung cancer cell. Hence, the CPNPs provided a new idea for treating cancer.


Assuntos
Neoplasias da Mama , Cisplatino , Glutationa/metabolismo , Neoplasias Pulmonares , Nanopartículas , Células A549 , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Cisplatino/química , Cisplatino/farmacocinética , Cisplatino/farmacologia , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Células MCF-7 , Sondas Moleculares/química , Sondas Moleculares/farmacocinética , Sondas Moleculares/farmacologia , Nanopartículas/química , Nanopartículas/uso terapêutico
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