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1.
Environ Microbiome ; 19(1): 22, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589941

RESUMO

BACKGROUND: Most researches on sponge holobionts focus primarily on symbiotic microbes, yet data at the level of the sponge hologenome are still relatively scarce. Understanding of the sponge host and its microbial gene expression profiles and the host-microbes interplay in different niches represents a key aspect of sponge hologenome. Using the Hawaiian demosponge Mycale grandis in different niches as a model, i.e. on rocks, on the surface of coral Porites compressa, under alga Gracilaria salicornia, we compared the bacterial and fungal community structure, functional gene diversity, expression pattern and the host transcriptome by integrating open-format (deep sequencing) and closed-format (GeoChip microarray) high-throughput techniques. RESULTS: Little inter-niche variation in bacterial and fungal phylogenetic diversity was detected for M. grandis in different niches, but a clear niche-dependent variability in the functional gene diversity and expression pattern of M. grandis host and its symbiotic microbiota was uncovered by GeoChip microarray and transcriptome analyses. Particularly, sponge host genes related to innate immunity and microbial recognition showed a strong correlation with the microbial symbionts' functional gene diversity and transcriptional richness in different niches. The cross-niche variability with respect to the symbiont functional gene diversity and the transcriptional richness of M. grandis holobiont putatively reflects the interplay of niche-specific selective pressure and the symbiont functional diversity. CONCLUSIONS: Niche-dependent gene expression profiles of M. grandis hologenome and the host-microbes interplay were suggested though little inter-niche variation in bacterial and fungal diversity was detected, particularly the sponge innate immunity was found to be closely related to the symbiotic microbes. Altogether, these findings provide novel insights into the black box of one sponge holobiont in different niches at the hologenome level.

2.
Nat Commun ; 15(1): 2313, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38485978

RESUMO

Arising from the extreme/saddle point in electronic bands, Van Hove singularity (VHS) manifests divergent density of states (DOS) and induces various new states of matter such as unconventional superconductivity. VHS is believed to exist in one and two dimensions, but rarely found in three dimension (3D). Here, we report the discovery of 3D VHS in a topological magnet EuCd2As2 by magneto-infrared spectroscopy. External magnetic fields effectively control the exchange interaction in EuCd2As2, and shift 3D Weyl bands continuously, leading to the modification of Fermi velocity and energy dispersion. Above the critical field, the 3D VHS forms and is evidenced by the abrupt emergence of inter-band transitions, which can be quantitatively described by the minimal model of Weyl semimetals. Three additional optical transitions are further predicted theoretically and verified in magneto-near-infrared spectra. Our results pave the way to exploring VHS in 3D systems and uncovering the coordination between electronic correlation and the topological phase.

3.
Plant Commun ; : 100827, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38297840

RESUMO

Plant synthetic biology research requires diverse bioparts that facilitate the redesign and construction of new-to-nature biological devices or systems in plants. Limited by few well-characterized bioparts for plant chassis, the development of plant synthetic biology lags behind that of its microbial counterpart. Here, we constructed a web-based Plant Synthetic BioDatabase (PSBD), which currently categorizes 1677 catalytic bioparts and 384 regulatory elements and provides information on 309 species and 850 chemicals. Online bioinformatics tools including local BLAST, chem similarity, phylogenetic analysis, and visual strength are provided to assist with the rational design of genetic circuits for manipulation of gene expression in planta. We demonstrated the utility of the PSBD by functionally characterizing taxadiene synthase 2 and its quantitative regulation in tobacco leaves. More powerful synthetic devices were then assembled to amplify the transcriptional signals, enabling enhanced expression of flavivirus non-structure 1 proteins in plants. The PSBD is expected to be an integrative and user-centered platform that provides a one-stop service for diverse applications in plant synthetic biology research.

4.
Plant Cell Rep ; 43(2): 44, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38246890

RESUMO

KEY MESSAGE: ZmWRKY64 positively regulates Arabidopsis and maize Cd stress through modulating Cd uptake, translocation, and ROS scavenging genes expression. Cadmium (Cd) is a highly toxic heavy metal with severe impacts on crops growth and development. The WRKY transcription factor is a significant regulator influencing plant stress response. Nevertheless, the function of the WRKY protein in maize Cd stress response remains unclear. Here, we identified a maize WRKY gene, ZmWRKY64, the expression of which was enhanced in maize roots and leaves under Cd stress. ZmWRKY64 was localized in the nucleus and displayed transcriptional activity in yeast. Heterologous expression of ZmWRKY64 in Arabidopsis diminished Cd accumulation in plants by negatively regulating the expression of AtIRT1, AtZIP1, AtHMA2, AtNRAMP3, and AtNRAMP4, which are involved in Cd uptake and transport, resulting in Cd stress tolerance. Knockdown of ZmWRKY64 in maize led to excessive Cd accumulation in leaf cells and in the cytosol of the root cells, resulting in a Cd hypersensitive phenotype. Further analysis confirmed that ZmWRKY64 positively regulated ZmABCC4, ZmHMA3, ZmNRAMP5, ZmPIN2, ZmABCG51, ZmABCB13/32, and ZmABCB10, which may influence Cd translocation and auxin transport, thus mitigating Cd toxicity in maize. Moreover, ZmWRKY64 could directly enhance the transcription of ZmSRG7, a reported key gene regulating reactive oxygen species homeostasis under abiotic stress. Our results indicate that ZmWRKY64 is important in maize Cd stress response. This work provides new insights into the WRKY transcription factor regulatory mechanism under a Cd-polluted environment and may lead to the genetic improvement of Cd tolerance in maize.


Assuntos
Arabidopsis , Fatores de Transcrição , Fatores de Transcrição/genética , Cádmio/toxicidade , Zea mays/genética , Arabidopsis/genética , Regulação da Expressão Gênica
5.
Nat Commun ; 15(1): 484, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212331

RESUMO

Previous studies on the molecular classification of cholangiocarcinoma (CCA) focused on certain anatomical sites, and disregarded tissue contamination biases in transcriptomic profiles. We aim to provide universal molecular classification scheme and prognostic biomarker of CCAs across anatomical locations. Comprehensive bioinformatics analysis is performed on transcriptomic data from 438 CCA cases across various anatomical locations. After excluding CCA tumors showing normal tissue expression patterns, we identify two universal molecular subtypes across anatomical subtypes, explore the molecular, clinical, and microenvironmental features of each class. Subsequently, a 30-gene classifier and a biomarker (called "CORE-37") are developed to predict the molecular subtype of CCA and prognosis, respectively. Two subtypes display distinct molecular characteristics and survival outcomes. Key findings are validated in external cohorts regardless of the stage and anatomical location. Our study provides a CCA classification scheme that complements the conventional anatomy-based classification and presents a promising prognostic biomarker for clinical application.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Transcriptoma , Prognóstico , Colangiocarcinoma/genética , Colangiocarcinoma/patologia , Ductos Biliares Intra-Hepáticos , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/patologia
6.
J Sci Food Agric ; 104(5): 2907-2916, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38029376

RESUMO

BACKGROUND: Rancidity causes unpleasant tastes and smells, and the degradation of fatty acids and natural antioxidants, so that an oil is unfit to be consumed. Natural antioxidants, including tocopherols, polyphenols (sesamol, canolol, ferulic acid, caffeic acid, etc.), ß-carotene, squalene and phytosterols, contribute to delay the oxidation of vegetable oils. However, studies on the combination of natural antioxidants to lengthen the shelf life of unsaturated fatty acid-rich blended oil have not been reported. RESULTS: All of the composite antioxidants had the potential to significantly improve the oxidation stability of blended oil. Blended oil G with 0.05 g kg-1 ß-carotene, 0.25 g kg-1 sesamol and 0.25 g kg-1 caffeic acid showed the best anti-autooxidation. It is also effective in improving the oxidative stability of vegetable oils containing various fatty acids. The oxidation stability index of the blended oil containing the optimum composition of natural antioxidants was 2.17-fold longer than that of the control sample. After the end of accelerated oxidation, the oil's peroxide value, p-anisidine value and total oxidation value were 6.59 times, 12.26 times and 6.65 times lower than those of the control sample, respectively. CONCLUSION: (1) The combination of natural antioxidants ß-carotene (0.05 g kg-1 ), sesamol (0.25 g kg-1 ) and caffeic acid (0.25 g kg-1 ) enhances the oxidative stability of unsaturated fatty acid-rich blended oils. (2) ß-Carotene is the main antioxidant in the early stages of oxidation. (3) Sesamol and caffeic acid are the main antioxidants in the middle and late stages of oxidation. © 2023 Society of Chemical Industry.


Assuntos
Antioxidantes , Benzodioxóis , Fenóis , beta Caroteno , Antioxidantes/química , Oxirredução , Ácidos Graxos Insaturados , Óleos de Plantas/química , Ácidos Graxos , Ácidos Cafeicos
7.
Magn Reson Imaging ; 104: 115-120, 2023 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-37844785

RESUMO

BACKGROUND: Patients with nasopharyngeal carcinoma (NPC) who undergo longitudinal follow-up contrast-enhanced MRI are at risk of developing gadolinium deposition in their neural tissue, which may potentially harm them. Therefore, for these patients, a non-contrast-enhanced method is potentially beneficial as an alternative approach to predict enhancement in T1-weighted imaging (CE-T1WI). The traditional intravoxel incoherent motion (IVIM) is one of the non-contrast-enhanced methods; however, the severe distortion and signal loss limit its application in patients with NPC. The present study aimed to investigate whether non-distortion IVIM could reduce the need of CE-T1WI in the follow-up of patients with NPC. METHODS: The patients with NPC underwent Turbo Spin-echo MVXD diffusion-weighted imaging-based IVIM (non-distortion IVIM) from November 2021 to May 2022. Firstly, thirty patients with NPC were underwent both non-distortion IVIM and traditional IVIM. The distortion rate (DR) of the non-distortion IVIM was compared with the traditional IVIM. Then, twenty-one NPC patients with tumors (areas >50mm2) were included and correlation coefficient analysis was used to assess the relationship between their non-distortion IVIM and CE-T1WI. Linear regression analysis was performed to determine whether non-distortion IVIM predictors could predict CE-T1WI. RESULTS: The correlation was observed between the parameter f of the non-distortion IVIM and the enhancement ratio of CE-T1WI (r = 0.543, P = 0.011). Moreover, the linear regression analysis revealed that f was an independent IVIM predictor of CE-T1WI in patients with NPC (P = 0.011). The DR of the non-distortion IVIM was significantly smaller than that of the traditional IVIM (0.12 ± 0.05 vs 0.48 ± 0.16, P < 0.001). CONCLUSIONS: In patients with NPC, non-distortion IVIM showed potential clinical benefits to reduce the need for contrast agents, and it can independently predict the enhancement ratio.

8.
J Immunother Cancer ; 11(10)2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37865396

RESUMO

BACKGROUND: The predictive efficacy of current biomarker of immune checkpoint inhibitors (ICIs) is not sufficient. This study investigated the causality between radiomic biomarkers and immunotherapy response status in patients with stage IB-IV non-small cell lung cancer (NSCLC), including its biological context for ICIs treatment response prediction. METHODS: CT images from 319 patients with pretreatment NSCLC receiving immunotherapy between January 2015 and November 2021 were retrospectively collected and composed a discovery (n=214), independent validation (n=54), and external test cohort (n=51). A set of 851 features was extracted from tumorous and peritumoral volumes of interest (VOIs). The reference standard is the durable clinical benefit (DCB, sustained disease control for more than 6 months assessed via radiological evaluation). The predictive value of combined radiomic signature (CRS) for pathological response was subsequently assessed in another cohort of 98 patients with resectable NSCLC receiving ICIs preoperatively. The association between radiomic features and tumor immune landscape on the online data set (n=60) was also examined. A model combining clinical predictor and radiomic signatures was constructed to improve performance further. RESULTS: CRS discriminated DCB and non-DCB patients well in the training and validation cohorts with an area under the curve (AUC) of 0.82, 95% CI: 0.75 to 0.88, and 0.75, 95% CI: 0.64 to 0.87, respectively. In this study, the predictive value of CRS was better than programmed cell death ligand-1 (PD-L1) expression (AUC of PD-L1 subset: 0.59, 95% CI: 0.50 to 0.69) or clinical model (AUC: 0.66, 95% CI: 0.51 to 0.81). After combining the clinical signature with CRS, the predictive performance improved further with an AUC of 0.837, 0.790 and 0.781 in training, validation and D2 cohorts, respectively. When predicting pathological response, CRS divided patients into a major pathological response (MPR) and non-MPR group (AUC: 0.76, 95% CI: 0.67 to 0.81). Moreover, CRS showed a promising stratification ability on overall survival (HR: 0.49, 95% CI: 0.27 to 0.89; p=0.020) and progression-free survival (HR: 0.43, 95% CI: 0.26 to 0.74; p=0.002). CONCLUSION: By analyzing both tumorous and peritumoral regions of CT images in a radiomic strategy, we developed a non-invasive biomarker for distinguishing responders of ICIs therapy and stratifying their survival outcome efficiently, which may support the clinical decisions on the use of ICIs in advanced as well as patients with resectable NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/tratamento farmacológico , Estudos Retrospectivos , Antígeno B7-H1 , Biomarcadores Tumorais , Imunoterapia/métodos
9.
Exp Cell Res ; 433(1): 113796, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37774763

RESUMO

Carcinogenesis and colorectal cancer (CRC) development are associated with dysregulation of various pathways, including Wnt and p53. 5-fluorouracil (5-FU) is a common chemotherapeutic agent for CRC treatment, but its efficacy is restricted by drug resistance. Doxycycline is an orally active tetracycline antibiotic known for its antimicrobial and anticancer cell proliferation activities. This study intends to delineate the potential role of bioinformatically predicted ZNF24 in the 5-FU resistance of CRC cells. The expression of ZNF24 was measured in clinically collected CRC tissues and cells. Afterward, ectopic ZNF24 expression was induced by DOX to evaluate the viability, colony-forming ability and sphere-forming ability of CRC cells. It was found that ZNF24 was validated to be poorly expressed in CRC tissues, and ectopic expression of ZNF24 was revealed to restrict the malignant phenotypes of CRC cells. In addition, restored ZNF24 attenuated 5-FU resistance of CRC cells by inhibiting the Wnt pathway and activating p53 signaling. Furthermore, an inhibitor of Wnt production 2 (IWP-2) treatment was an alternative to ZNF24 up-regulation in sensitizing CRC cells to 5-FU treatment. In conclusion, our results indicate that ZNF24 inhibits 5-FU resistance of CRC cells by suppressing the Wnt pathway and activating p53 signaling, which offers a potential strategy for managing chemoresistance in CRC.

10.
Soc Sci Med ; 335: 116214, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37716183

RESUMO

School racial segregation is increasingly recognized as a threat to US public health: rising segregation in recent decades has been linked to a range of poor health outcomes for Black Americans. Key theorized mediators of these harms remain underexamined, including experiences of interpersonal and institutional racism driving increased stress, and peers' health behaviors influencing students' own. Using cross-sectional survey data on a national sample of adolescents, we investigated associations between school segregation and these two potential mediating pathways, operationalized as adolescents' perceptions of prejudice from fellow students and the health behaviors of their peers (drinking and smoking). We further investigated whether associations were modified by individual race/ethnicity and school racial composition. Pooling across all schools and students, higher levels of school segregation were associated with decreased perceptions of peer prejudice (OR 0.54, 95% CI = 0.34-0.86), but not with peers' health behaviors. However, this masked important differences by respondents' race/ethnicity and school racial/ethnic composition. In predominantly White schools, school segregation was not associated with Black students' perceptions of peers' prejudice, but higher levels of segregation were associated with increased rates of peers' drinking and smoking. In predominantly non-White schools, in contrast-where most Black students are educated-higher levels of school segregation were not associated with perceived peer prejudice nor unhealthier peer behaviors for Black students (in fact, peers' health behaviors improved). And across both school types, higher levels of district segregation were associated with lower odds of reporting peer prejudice among non-Black students of color. Our findings suggest that the paths between school segregation and poor health depend on the type of school children attend in segregated districts. In schools predominantly serving students of color, structural factors upheld by school segregation-i.e., material, educational, disciplinary, or economic disadvantage-likely dominate over peer behaviors as the primary drivers of segregation's health harms.


Assuntos
Etnicidade , Preconceito , Adolescente , Criança , Humanos , Estudos Transversais , Instituições Acadêmicas , Comportamentos Relacionados com a Saúde
11.
Gut ; 72(11): 2149-2163, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37549980

RESUMO

OBJECTIVE: Selecting interventions for patients with solitary hepatocellular carcinoma (HCC) remains a challenge. Despite gross classification being proposed as a potential prognostic predictor, its widespread use has been restricted due to inadequate studies with sufficient patient numbers and the lack of established mechanisms. We sought to investigate the prognostic impacts on patients with HCC of different gross subtypes and assess their corresponding molecular landscapes. DESIGN: A prospective cohort of 400 patients who underwent hepatic resection for solitary HCC was reviewed and analysed and gross classification was assessed. Multiomics analyses were performed on tumours and non-tumour tissues from 49 patients to investigate the mechanisms underlying gross classification. Inverse probability of treatment weight (IPTW) was used to control for confounding factors. RESULTS: Overall 3-year survival rates varied significantly among the four gross subtypes (type I: 91%, type II: 80%, type III: 74.6%, type IV: 38.8%). Type IV was found to be independently associated with poor prognosis in both the entire cohort and the IPTW cohort. The four gross subtypes exhibited three distinct transcriptional modules. Particularly, type IV tumours exhibited increased angiogenesis and immune score as well as decreased metabolic pathways, together with highest frequency of TP53 mutations. Patients with type IV HCC may benefit from adjuvant intra-arterial therapy other than the other three subtypes. Accordingly, a modified trichotomous margin morphological gross classification was established. CONCLUSION: Different gross types of HCC showed significantly different prognosis and molecular characteristics. Gross classification may aid in development of precise individualised diagnosis and treatment strategies for HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Estudos Prospectivos , Multiômica , Prognóstico
12.
Foods ; 12(11)2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37297517

RESUMO

The effects of endogenous anti-oxidative components of ten common edible vegetable oils (palm olein, corn oil, rapeseed oil, soybean oil, perilla seed oil, high oleic sunflower oil, peanut oil, camellia oil, linseed oil, and sesame oil) on oxidation were explored in this research. The oxidation processes and patterns of the oils were investigated with the Schaal oven test using fatty acids and the oxidative stability index, acid value, peroxide value, p-anisidine value, total oxidation value, and content of major endogenous anti-oxidative components as indicators. The major endogenous anti-oxidative components in vegetable oils were tocopherols, sterols, polyphenols, and squalene, among which α-tocopherol, ß-sitosterol, and polyphenols showed good anti-oxidative activity. However, squalene and polyphenols were relatively low and showed limited anti-oxidative effects. Moreover, the oxidative stability index of edible vegetable oils oxidized at high temperature (120 °C) was positively correlated with the content of saturated fatty acids (r = 0.659) and negatively correlated with the content of polyunsaturated fatty acids (r = -0.634) and calculated oxidizability (r = -0.696). When oxidized at a low temperature (62 °C), oxidative stability was influenced by a combination of fatty acid composition as well as endogenous anti-oxidative components. An improved TOPSIS based on Mahalanobis distance was used to evaluate the oxidative stability of different types of vegetable oils. Moreover, the oxidative stability of corn oil was better than the other vegetable oils, while perilla seed oil was very weak.

13.
J Fungi (Basel) ; 9(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37367576

RESUMO

Fungi have long been known to be dynamic in coastal water columns with multiple trophic modes. However, little is known about their interactions with abiotic and biotic components, contribution to the biological carbon pump (BCP), and organic matter remineralization in the oceanic water column. In this study, we investigated how fungi vary spatially and how their variations relate to that of bacteria in the water column of the South China Sea (SCS). Fungi were about three orders less prevalent than bacteria, and the main factors influencing their distribution were depth, temperature, and distance from the sites of riverine inputs. The decline in the abundance of fungi with depth was less steep than that of bacteria. Correlation tests revealed a strong positive association between the abundance of fungi and bacteria, especially in the twilight (r = 0.62) and aphotic (r = 0.70) zones. However, the co-occurrence network revealed mutual exclusion between certain members of fungi and bacteria. The majority of fungi in the water column were saprotrophs, which indicated that they were generally involved in the degradation of organic matter, particularly in twilight and aphotic zones. Similar to bacteria, the involvement of fungi in the metabolism of carbohydrates, proteins, and lipids was predicted, pointing to their participation in the turnover of organic carbon and the biogeochemical cycling of carbon, nitrogen, and sulfur. These findings suggest that fungi play a role in BCP and support their inclusion in marine microbial ecosystem models.

14.
Antioxidants (Basel) ; 12(5)2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-37237900

RESUMO

Media supplementation has proven to be an effective technique for improving byproduct yield during microbial fermentation. This study explored the impact of different concentrations of bioactive compounds, namely alpha-tocopherol, mannitol, melatonin, sesamol, ascorbic acid, and biotin, on the Aurantiochytrium sp. TWZ-97 culture. Our investigation revealed that alpha-tocopherol was the most effective compound in reducing the reactive oxygen species (ROS) burden, both directly and indirectly. Adding 0.7 g/L of alpha-tocopherol led to an 18% improvement in biomass, from 6.29 g/L to 7.42 g/L. Moreover, the squalene concentration increased from 129.8 mg/L to 240.2 mg/L, indicating an 85% improvement, while the squalene yield increased by 63.2%, from 19.82 mg/g to 32.4 mg/g. Additionally, our comparative transcriptomics analysis suggested that several genes involved in glycolysis, pentose phosphate pathway, TCA cycle, and MVA pathway were overexpressed following alpha-tocopherol supplementation. The alpha-tocopherol supplementation also lowered ROS levels by binding directly to ROS generated in the fermentation medium and indirectly by stimulating genes that encode antioxidative enzymes, thereby decreasing the ROS burden. Our findings suggest that alpha-tocopherol supplementation can be an effective method for improving squalene production in Aurantiochytrium sp. TWZ-97 culture.

15.
Chaos ; 33(5)2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37229636

RESUMO

Negative capacitance usually exists in ferroelectric materials, and its instinct nonlinearity and negative capacitance render its potential applications. To date, the single negative capacitance device is commonly unavailable. Hence, it is necessary to build a negative capacitor emulator in hardware for further investigating its electrical characteristics and applications. Based on a simple negative capacitor mathematical model, an emulator circuit that can mimic the S-shaped voltage-charge characteristics of the negative capacitor is proposed. The proposed emulator is composed of commercial off-the-shelf components, such as operational amplifiers, resistors, and capacitors. Based on the negative capacitor, we design a new chaotic circuit that can generate the single-period, double-period, single-scroll chaos, double-scroll chaos, and so on. The theoretical calculation, simulation analysis, and hardware experimental verification manifest that this proposed emulator circuit can be operated as a negative capacitor and applied in the chaotic circuit.

16.
Mar Drugs ; 21(4)2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-37103338

RESUMO

Thraustochytrids are unicellular marine heterotrophic protists, which have recently shown a promising ability to produce omega-3 fatty acids from lignocellulosic hydrolysates and wastewaters. Here we studied the biorefinery potential of the dilute acid-pretreated marine macroalgae (Enteromorpha) in comparison with glucose via fermentation using a previously isolated thraustochytrid strain (Aurantiochytrium limacinum PKU#Mn4). The total reducing sugars in the Enteromorpha hydrolysate accounted for 43.93% of the dry cell weight (DCW). The strain was capable of producing the highest DCW (4.32 ± 0.09 g/L) and total fatty acids (TFA) content (0.65 ± 0.03 g/L) in the medium containing 100 g/L of hydrolysate. The maximum TFA yields of 0.164 ± 0.160 g/g DCW and 0.196 ± 0.010 g/g DCW were achieved at 80 g/L of hydrolysate and 40 g/L of glucose in the fermentation medium, respectively. Compositional analysis of TFA revealed the production of equivalent fractions (% TFA) of saturated and polyunsaturated fatty acids in hydrolysate or glucose medium. Furthermore, the strain yielded a much higher fraction (2.61-3.22%) of eicosapentaenoic acid (C20:5n-3) in the hydrolysate medium than that (0.25-0.49%) in the glucose medium. Overall, our findings suggest that Enteromorpha hydrolysate can be a potential natural substrate in the fermentative production of high-value fatty acids by thraustochytrids.


Assuntos
Ácidos Graxos Insaturados , Estramenópilas , Fermentação , Ácidos Graxos , Glucose , Carboidratos da Dieta , Ácidos Docosa-Hexaenoicos
17.
Chin Med J (Engl) ; 136(7): 840-847, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37027252

RESUMO

BACKGROUND: Cholecystectomy is a standard surgery for patients suffering from gallbladder diseases, while the causal effects of cholecystectomy on colorectal cancer (CRC) and other complications are still unknown. METHODS: We obtained genetic variants associated with cholecystectomy at a genome-wide significant level ( P value <5 × 10 -8 ) as instrumental variables (IVs) and performed Mendelian randomization (MR) to identify the complications of cholecystectomy. Furthermore, the cholelithiasis was also treated as the exposure to compare its causal effects to those of cholecystectomy, and multivariable MR analysis was carried out to judge whether the effect of cholecystectomy was independent of cholelithiasis. The study was reported based on Strengthening the Reporting of Observational Studies in Epidemiology Using Mendelian Randomization guidelines. RESULTS: The selected IVs explained 1.76% variance of cholecystectomy. Our MR analysis suggested that cholecystectomy cannot elevate the risk of CRC (odds ratio [OR] =1.543, 95% confidence interval [CI]: 0.607-3.924). Also, it was not significant in either colon or rectum cancer. Intriguingly, cholecystectomy might decrease the risk of Crohn's disease (OR = 0.078, 95% CI: 0.016-0.368) and coronary heart disease (OR = 0.352, 95% CI: 0.164-0.756). However, it might increase the risk of irritable bowel syndrome (IBS) (OR = 7.573, 95% CI: 1.096-52.318). Cholelithiasis could increase the risk of CRC in the largest population (OR = 1.041, 95% CI: 1.010-1.073). The multivariable MR analysis suggested that genetic liability to cholelithiasis could increase the risk of CRC in the largest population (OR = 1.061, 95% CI: 1.002-1.125) after adjustment of cholecystectomy. CONCLUSIONS: The study indicated that cholecystectomy might not increase the risk of CRC, but such a conclusion needs further proving by clinical equivalence. Additionally, it might increase the risk of IBS, which should be paid attention to in clinical practice.


Assuntos
Colelitíase , Neoplasias Colorretais , Síndrome do Intestino Irritável , Humanos , Análise da Randomização Mendeliana , Neoplasias Colorretais/genética , Colelitíase/genética , Colelitíase/complicações , Colecistectomia/efeitos adversos , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único
18.
Chaos ; 33(2): 023120, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36859197

RESUMO

Neuromorphic computing provides unique computing and memory capabilities that could break the limitation of conventional von Neumann computing. Toward realizing neuromorphic computing, fabrication and synthetization of hardware elements and circuits to emulate biological neurons are crucial. Despite the striking progress in exploring neuron circuits, the existing circuits can only reproduce monophasic action potentials, and no studies report on circuits that could emulate biphasic action potentials, limiting the development of neuromorphic devices. Here, we present a simple third-order memristive circuit built with a classical symmetrical Chua Corsage Memristor (SCCM) to accurately emulate biological neurons and show that the circuit can reproduce monophasic action potentials, biphasic action potentials, and chaos. Applying the edge of chaos criterion, we calculate that the SCCM and the proposed circuit have the symmetrical edge of chaos domains with respect to the origin, which plays an important role in generating biphasic action potentials. Also, we draw a parameter classification map of the proposed circuit, showing the edge of chaos domain (EOCD), the locally active domain, and the locally passive domain. Near the calculated EOCD, the third-order circuit generates monophasic action potentials, biphasic action potentials, chaos, and ten types of symmetrical bi-directional neuromorphic phenomena by only tuning the input voltage, showing a resemblance to biological neurons. Finally, a physical SCCM circuit and some experimentally measured neuromorphic waveforms are exhibited. The experimental results agree with the numerical simulations, verifying that the proposed circuit is suitable as artificial neurons.

19.
Microb Cell Fact ; 22(1): 52, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36918882

RESUMO

BACKGROUND: Thraustochytrids accumulate lipids with a high content of docosahexaenoic acid (DHA). Although their growth and DHA content are significantly affected by the dissolved oxygen (DO) supply, the role of DO on the transcriptional regulation of metabolism and accumulation of intracellular metabolites remains poorly understood. Here we investigate the effects of three different DO supply conditions (10%, 30%, and 50%) on the fed-batch culture of the Aurantiochytrium PKU#Mn16 strain to mainly reveal the differential gene expressions and metabolite profiles. RESULTS: While the supply of 10% DO significantly reduced the rates of biomass and DHA production in the early stages of fermentation, it achieved the highest amounts of biomass (56.7 g/L) and DHA (6.0 g/L) on prolonged fermentation. The transcriptome analyses of the early stage (24 h) of fermentation revealed several genes involved in the central carbon, amino acid, and fatty acid metabolism, which were significantly downregulated at a 10% DO level. The comparative metabolomics results revealed the accumulation of several long-chain fatty acids, amino acids, and other metabolites, supporting the transcriptional regulation under the influence of a low oxygen supply condition. In addition, certain genes involved in antioxidative systems were downregulated under 10% DO level, suggesting a lesser generation of reactive oxygen species that lead to oxidative damage and fatty acid oxidation. CONCLUSIONS: The findings of this study suggest that despite the slow growth and metabolism in the early stage of fermentation of Aurantiochytrium sp. PKU#Mn16, a constant supply of low dissolved oxygen can yield biomass and DHA content better than that with high oxygen supply conditions. The critical information gained in this study will help to further improve DHA production through bioprocess engineering strategies.


Assuntos
Ácidos Docosa-Hexaenoicos , Estramenópilas , Ácidos Docosa-Hexaenoicos/metabolismo , Fermentação , Ácidos Graxos/metabolismo , Metabolismo dos Lipídeos , Estramenópilas/genética , Oxigênio/metabolismo
20.
Microorganisms ; 11(3)2023 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-36985166

RESUMO

The consequences of climate change may directly or indirectly impact the marine biosphere. Although ocean stratification has been recognized as one of the crucial consequences of ocean warming, its impacts on several critical aspects of marine microbes remain largely unknown in the Indian Ocean. Here, we investigate the effects of water stratification, in both surface and subsurface layers, on hydrogeographic parameters and bacterioplankton diversity within the equatorial eastern Indian Ocean (EIO). Strong stratification in the upper 200 m of equatorial EIO was detected with evidential low primary productivity. The vertical bacterioplankton diversity of the whole water columns displayed noticeable variation, with lower diversity occurring in the surface layer than in the subsurface layers. Horizontal heterogeneity of bacterioplankton communities was also in the well-mixed layer among different stations. SAR11 and Prochlorococcus displayed uncharacteristic low abundance in the surface water. Some amplicon sequence variants (ASVs) were identified as potential biomarkers for their specific depths in strongly-stratified water columns. Thus, barriers resulting from stratification are proposed to function as an 'ASV filter' to regulate the vertical bacterioplankton community diversity along the water columns. Overall, our results suggest that the effects of stratification on the structure and diversity of bacterioplankton can extend up to the bathypelagic zone in the strongly-stratified waters of the equatorial EIO. This study provides the first insight into the effect of stratification on the subsurface microbial communities in the equatorial eastern Indian Ocean.

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