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1.
Appl Environ Microbiol ; 90(7): e0054024, 2024 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-38829054

RESUMO

Halophilic archaea are promising microbial cell factories for bacterioruberin (BR) production. BR is a natural product with multi-bioactivities, allowing potential application in many fields. In the previous work, a haloarchaeon Halorubrum sp. HRM-150 with a high proportion of BR (about 85%) was isolated, but the low yield impeded its large-scale production. This work figured out BR synthesis characteristics and mechanisms, and proposed strategies for yield improvement. First, glucose (10 g/L) and tryptone (15 g/L) were tested to be better sources for BR production. Besides, the combination of glucose and starch achieved the diauxic growth, and the biomass and BR productivity increased by 85% and 54% than using glucose. Additionally, this work first proposed the BR synthesis pattern, which differs from that of other carotenoids. As a structural component of cell membranes, the BR synthesis is highly coupled with growth, which was most active in the logarithm phase. Meanwhile, the osmotic down shock at the logarithm phase could increase the BR productivity without sacrificing the biomass. Moreover, the de-novo pathway for BR synthesis with a key gene of lyeJ, and its competitive pathways (notably tetraether lipids and retinal) were revealed through genome, transcriptome, and osmotic down shock. Therefore, the BR yield is expected to be improved through mutant construction, such as the overexpression of key gene lyeJ and the knockout of competitive genes, which need to be further explored. The findings will contribute to a better understanding of the metabolism mechanism in haloarchaea and the development of haloarchaea as microbial cell factories. IMPORTANCE: Recent studies have revealed that halophilic microorganism is a promising microbial factory for the next-generation industrialization. Among them, halophilic archaea are advantageous as microbial factories due to their low contamination risk and low freshwater consumption. The halophilic archaea usually accumulate long chain C50 carotenoids, which are barely found in other organisms. Bacterioruberin (BR), the major C50 carotenoid, has multi-bioactivities, allowing potential application in food, cosmetic, and biomedical industries. However, the low yield impedes its large-scale application. This work figured out the BR synthesis characteristics and mechanism, and proposed several strategies for BR yield improvement, encouraging halophilic archaea to function as microbial factories for BR production. Meanwhile, the archaea have special evolutionary status and unique characteristics in taxonomy, the revelation of BR biosynthesis mechanism is beneficial for a better understanding of archaea.


Assuntos
Carotenoides , Perfilação da Expressão Gênica , Genoma Arqueal , Carotenoides/metabolismo , Halorubrum/genética , Halorubrum/metabolismo , Halorubrum/crescimento & desenvolvimento , Transcriptoma , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo
2.
Anim Genet ; 54(4): 570-575, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37185969

RESUMO

Excitability is a pivotal quality in guide dogs because moderately active dogs are more trainable. Excessive activity is associated with behavioral problems and pet surrender. Excitability is a highly heritable trait, yet the relevant genetic factors and markers associated with this condition are poorly characterized. In the present study, we selected six single nucleotide polymorphisms (SNPs) of two genes that are possibly related to excitability in dogs (TH c.264G > A, TH c.1208A > T, TH c.415C > G, TH c.168C > T, TH c.180C > T and MAOB c.199 T > C). We measured the excitability of dogs using seven variables from three behavioral tests: the play test (interest in play, grabbing in throw and tug-of-war), the chase test (following and forward grabbing) and the passive test (moving range and moving time). These behavioral tests are part of the Dog Mentality Assessment developed by Svartberg & Forkman. The activity scores in the guide dog group were higher than in the temperament withdrawal group, and significant differences were detected in the aggregate score (p = 0.02), passive activity score (p = 0.007) and moving range score (p = 0.04). Analysis using the Kruskal-Wallis test and non-parametric Steel-Dwass test to evaluate the relationship between these SNPs and behavioral variable scores revealed that TH c.264G > A was associated with aggregate scores of excitability-related behavioral variables (adj. p = 0.03), object-interaction activity scores (adj. p = 0.03), following scores (adj. p = 0.03) and forward grabbing scores (adj. p = 0.03) in Labrador dogs and MAOB c.199 T > C was associated with moving range scores in these dogs (adj. p = 0.004). However, these results had low power. To explain the behavioral traits, further genetic studies more reliable than candidate gene studies are needed.


Assuntos
Polimorfismo de Nucleotídeo Único , Cães , Animais , Fenótipo
3.
Bioengineering (Basel) ; 10(11)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38002422

RESUMO

Background: this study aimed to utilize various diffusion-weighted imaging (DWI) techniques, including mono-exponential DWI, intravoxel incoherent motion (IVIM), and diffusion kurtosis imaging (DKI), for the preoperative grading of rectal cancer. Methods: 85 patients with rectal cancer were enrolled in this study. Mann-Whitney U tests or independent Student's t-tests were conducted to identify DWI-derived parameters that exhibited significant differences. Spearman or Pearson correlation tests were performed to assess the relationships among different DWI-derived biological markers. Subsequently, four machine learning classifier-based models were trained using various DWI-derived parameters as input features. Finally, diagnostic performance was evaluated using ROC analysis with 5-fold cross-validation. Results: With the exception of the pseudo-diffusion coefficient (Dp), IVIM-derived and DKI-derived parameters all demonstrated significant differences between low-grade and high-grade rectal cancer. The logistic regression-based machine learning classifier yielded the most favorable diagnostic efficacy (AUC: 0.902, 95% Confidence Interval: 0.754-1.000; Specificity: 0.856; Sensitivity: 0.925; Youden Index: 0.781). Conclusions: utilizing multiple DWI-derived biological markers in conjunction with a strategy employing multiple machine learning classifiers proves valuable for the noninvasive grading of rectal cancer.

4.
Front Cardiovasc Med ; 10: 1130388, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37057103

RESUMO

Background: Tissue inhibitor of metalloproteinase 3 (TIMP3) was recently demonstrated capable to regulate some gene expression in a myocardial infarction model. Here we aim to explore the gene expression profile in TIMP3-treated cardiomyocytes and related potential cardiovascular functions. Methods: Total RNA extracted from cultured neonatal rat ventricular myocytes (NRVMs) were used for RNA sequencing analysis and real-time PCR. KEGG pathway enrichment assay and Ingenuity Pathway Analysis (IPA) were performed to study the signaling pathways and downstream effects. Western blot was used to detect phosphorylation of protein kinase B (Akt). A Cell Counting Kit-8 assay was employed to evaluate the proliferation of human umbilical vein endothelial cells (HUVECs). Contraction rate of NRVMs was measured with microscopy. Results: RNA sequencing data showed that expression of 2,526 genes were significantly modulated by recombinant TIMP3 (rTIMP3, 100 ng/ml) in NRVMs. Some differentially expressed genes (DEGs) were validated with real-time PCR. Several KEGG pathways including the phosphoinositide-3-kinase (PI3K)-Akt pathway were significantly regulated by rTIMP3. Phosphorylation of Akt was increased by rTIMP3 and a PI3K inhibitor LY294002 suppressed rTIMP3-induced up-regulation of some genes. Some DEGs were predicted by IPA to increase vascularization, and some to decrease heart rate. RTIMP3 could reduce the contraction rate of NRVMs and its conditioned media increased the proliferation of HUVECs. Conclusion: TIMP3 can regulate expression of multiple genes partly through PI3K. Some DEGs were associated with activation of vascularization and some with heart rate reduction. This study suggests that TIMP3 can potentially modulate cardiovascular functions via DEGs.

5.
J Hazard Mater ; 430: 128468, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35180523

RESUMO

Photocatalysis technology has been widely adopted to abate typical air pollutants. Nevertheless, developing photocatalysts aimed at improving photocatalytic efficiency is a challenge. Herein, the linker-defect NH2-MIL-125(Ti) photocatalyst was synthesized through a convenient one-step heating-stirring method (just adjusting multiple temperatures) to firstly realize efficient photocatalytic performances of NO removal and hydrogen evolution. The optimal sample (named 65-NMIL) with a linker-defect content of 32.08% exhibited a NO removal ratio of 65.49%, which was 37.57% higher than that of pristine NH2-MIL-125(Ti), and displayed better H2-production activity. Through ESR, it was confirmed that 65-NMIL can generate more •O2- and •OH under visible light, and the radical trapping experiment further proved that •O2- played a more important role in photocatalytic activity. Moreover, the photocatalytic NO oxidation process was also monitored by in situ DRIFTS, it was found that the defective samples could promote the oxidation of NO and intermediates to the final product (NO3-). On the basis of the above-mentioned photocatalytic experimental results and characterization, a possible mechanism or pathway was proposed and illustrated. This work can provide a new strategy for the subsequent defect engineering for photocatalytic MOFs materials to further solve environmental and energy crises.


Assuntos
Prótons , Titânio , Catálise , Oxirredução
6.
Front Oncol ; 11: 695001, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34616672

RESUMO

Hepatocellular carcinoma is a common malignant tumor with poor prognosis, poor treatment effect, and lack of effective biomarkers. In this study, bioinformatics analysis of immune-related genes of hepatocellular carcinoma was used to construct a multi-gene combined marker that can predict the prognosis of patients. The RNA expression data of hepatocellular carcinoma were downloaded from The Cancer Genome Atlas (TCGA) database, and immune-related genes were obtained from the IMMPORT database. Differential analysis was performed by Wilcox test to obtain differentially expressed genes. Univariate Cox regression analysis, lasso regression analysis and multivariate Cox regression analysis were performed to establish a prognostic model of immune genes, a total of 5 genes (HDAC1, BIRC5, SPP1, STC2, NR6A1) were identified to construct the models. The expression levels of 5 genes in HCC tissues were significantly different from those in paracancerous tissues. The Kaplan-Meier survival curve showed that the risk score calculated according to the prognostic model was significantly related to the overall survival (OS) of HCC. The receiver operating characteristic (ROC) curve confirmed that the prognostic model had high accuracy. Independent prognostic analysis was performed to prove that the risk value can be used as an independent prognostic factor. Then, the gene expression data of hepatocellular carcinoma in the ICGC database was used as a validation data set for the verification of the above steps. In addition, we used the CIBERSORT software and TIMER database to conduct immune infiltration research, and the results showed that the five genes of the model and the risk score have a certain correlation with the content of immune cells. Moreover, through Gene Set Enrichment Analysis (GSEA) and the construction of protein interaction networks, we found that the p53-mediated signal transduction pathway is a potentially important signal pathway for hepatocellular carcinoma and is positively regulated by certain genes in the prognostic model. In conclusion, this study provides potential targets for predicting the prognosis and treatment of hepatocellular carcinoma patients, and also provides new ideas about the correlation between immune genes and potential pathways of hepatocellular carcinoma.

7.
Stapp Car Crash J ; 63: 331-342, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32311063

RESUMO

This paper presents the development of a sensor suite that is used to measure the toeboard threedimensional (3D) dynamic deformation during a crash test, along with the methodology to use the sensor suite for toeboard measurement. The sensor suite consists of three high-speed cameras, which are firmly connected through a rigid metal frame. Two cameras, facing directly towards the toeboard, measure the shape of the toeboard through stereovision. The third camera, facing the ground, is equipped with a three-axis gyroscope and a three-axis accelerometer and localizes the sensor suite globally for removing the vibration of the sensor suite. The sensor suite was mounted onto the car through car seat mounting bolt holes, and a hole was made on the floor to let the downward camera see the ground. A pipeline using the data collected by the sensor suite is also introduced in this paper. A 56 km/h frontal barrier crash test was conducted to validate the capability of the sensor suite and a sled test was conducted to test the measuring accuracy of the purposed system. The results show that the proposed sensor suite identified its position and orientation, which allowed the removal of vibration of the stereo camera. The measuring accuracy, which is neither temporal nor positional, was 1.3 mm. The proposed methodology, as a result, has measured the global 3D deformation of the toeboard during crash with a measuring accuracy of 1.3mm.


Assuntos
Acidentes de Trânsito , Veículos Automotores , , Fenômenos Mecânicos , Vibração
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