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1.
Int J Cancer ; 153(3): 499-511, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37087737

RESUMEN

Previous investigations mainly focused on the associations of dietary fatty acids with colorectal cancer (CRC) risk, which ignored gene-environment interaction and mechanisms interpretation. We conducted a case-control study (751 cases and 3058 controls) and a prospective cohort study (125 021 participants) to explore the associations between dietary fatty acids, genetic risks, and CRC. Results showed that high intake of saturated fatty acid (SFA) was associated with a higher risk of CRC than low SFA intake (HR =1.22, 95% CI:1.02-1.46). Participants at high genetic risk had a greater risk of CRC with the HR of 2.48 (2.11-2.91) than those at low genetic risk. A multiplicative interaction of genetic risk and SFA intake with incident CRC risk was found (PInteraction = 7.59 × 10-20 ), demonstrating that participants with high genetic risk and high SFA intake had a 3.75-fold greater risk of CRC than those with low genetic risk and low SFA intake. Furthermore, incorporating PRS and SFA into traditional clinical risk factors improved the discriminatory accuracy for CRC risk stratification (AUC from 0.706 to 0.731). Multi-omics data showed that exposure to SFA-rich high-fat dietary (HFD) can responsively induce epigenome reprogramming of some oncogenes and pathological activation of fatty acid metabolism pathway, which may contribute to CRC development through changes in gut microbiomes, metabolites, and tumor-infiltrating immune cells. These findings suggest that individuals with high genetic risk of CRC may benefit from reducing SFA intake. The incorporation of SFA intake and PRS into traditional clinical risk factors will help improve high-risk sub-populations in individualized CRC prevention.


Asunto(s)
Neoplasias Colorrectales , Grasas de la Dieta , Humanos , Estudios Prospectivos , Estudios de Casos y Controles , Grasas de la Dieta/efectos adversos , Factores de Riesgo , Ácidos Grasos/efectos adversos , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/inducido químicamente
2.
Arch Toxicol ; 97(7): 2015-2028, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37245169

RESUMEN

Although genome-wide association studies (GWASs) have identified over 100 colorectal cancer (CRC) risk loci, an understanding of causal genes or risk variants and their biological functions in these loci remain unclear. Recently, genomic loci 10q26.12 with lead SNP rs1665650 was identified as an essential CRC risk loci of Asian populations. However, the functional mechanism of this region has not been fully clarified. Here, we applied an RNA interfering-based on-chip approach to screen for the genes essential for cell proliferation in the CRC risk loci 10q26.12. Notably, HSPA12A had the most significant effect among the identified genes and functioned as a crucial oncogene facilitating cell proliferation. Moreover, we conducted an integrative fine-mapping analysis to identify putative casual variants and further explored their association with CRC risk in a large-scale Chinese population consisting of 4054 cases and 4054 controls and also independently validated in 5208 cases and 20,832 controls from the UK biobank cohort. We identified a risk SNP rs7093835 in the intron of HSPA12A that was significantly associated with an increased risk of CRC (OR 1.23, 95% CI 1.08-1.41, P = 1.92 × 10-3). Mechanistically, the risk variant could facilitate an enhancer-promoter interaction mediated by the transcriptional factor (TF) GRHL1 and ultimately upregulate HSPA12A expression, which provides functional evidence to support our population findings. Collectively, our study reveals the important role of HSPA12A in CRC development and illustrates a novel enhancer-promoter interaction module between HSPA12A and its regulatory elements rs7093835, providing new insights into the etiology of CRC.


Asunto(s)
Neoplasias Colorrectales , Estudio de Asociación del Genoma Completo , Humanos , Predisposición Genética a la Enfermedad , Regiones Promotoras Genéticas , Riesgo , Neoplasias Colorrectales/genética , Polimorfismo de Nucleótido Simple , Estudios de Casos y Controles , Proteínas HSP70 de Choque Térmico/genética
3.
Environ Sci Technol ; 56(17): 12315-12324, 2022 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-35969222

RESUMEN

Siderophores and iron-containing clays are known to influence the transformation of chromium in the environment. The role of clays in hexavalent chromium [Cr(VI)] reduction has been reported extensively. However, the mechanisms of Cr(VI) reduction by siderophores and their combination with iron-bearing clays are poorly known. Herein, we report the kinetics and products of Cr(VI) reduction by a siderophore alone or in combination with reduced clays. Results showed that Cr(VI) reduction by a tri-hydroxamate siderophore─desferrioxamine B (DFOB)─at a pH of 6 was achieved by one-electron transfer via the formation of Cr(V) intermediate. The formed Cr(V) was further reduced to organically complexed Cr(III). The Cr(VI) reduction rate and extent in the presence of both DFOB and reduced clays unexpectedly decreased relative to that with reduced clays alone, despite both serving as Cr(VI) reductants. The interaction between DFOB and clays (e.g., adsorption/intercalation, dissolution, and/or oxidation) was primarily responsible for Cr(VI) reduction inhibition. The extent of inhibition increased at higher DFOB concentrations in the presence of iron-rich nontronite but decreased in the presence of iron-poor montmorillonite, which may be related to their different Cr(VI) reduction mechanisms. This study highlights the importance of siderophores in chromium transformation and its impact on the reactivity of iron-bearing clays toward heavy metal reduction in the environment.


Asunto(s)
Cromo , Sideróforos , Arcilla , Hierro , Minerales , Oxidación-Reducción
4.
Genomics ; 113(5): 2934-2943, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34182079

RESUMEN

Miniature inverted-repeat transposable elements (MITEs) are a group of class II transposable elements. The MITE Monkey King (MK) was first discovered upstream of BnFLC.A10. In this study, genome resequencing of four selected B. napus accessions, revealed more than 4000 distributed copies of MKs constituting ~2.4 Mb of the B. napus genomic sequence and caused 677 polymorphisms among the four accessions. MK -polymorphism-related markers across 128 natural and 58 synthetic accessions revealed more polymorphic MKs in natural than synthetic accessions. Ten MK -induced indels significantly affected the expression levels of the nearest gene based on RNAseq analysis, six of these effects were subsequently confirmed using qRT-PCR. Decreased expression pattern of MK -derived miRNA-bna-miR6031 was also observed under various stress treatments. Further research focused on the MITE families should promote not only our understanding of gene regulatory networks but also inform crop improvement efforts.


Asunto(s)
Brassica napus , MicroARNs , Brassica napus/genética , Elementos Transponibles de ADN , Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genoma de Planta , MicroARNs/genética
5.
Opt Express ; 28(26): 39084-39092, 2020 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-33379466

RESUMEN

We report on the nonlinear characterizations of the titanium dioxide micro-ring resonators (TiO2 MRRs). By utilizing optimized fabrication processes, high quality factors (Q∼1.4 × 105) doubling that of the previous work are achieved here for TiO2 MRRs with high-confinement TiO2 waveguides. The four-wave mixing (FWM) experiment results with low and high signal power demonstrate that, the fabricated TiO2 MRRs can perform broadband (∼40 nm) wavelength conversion and cascaded FWMs. These achievements pave the way for key nonlinear photonic applications with TiO2 waveguides and provide an efficient platform for various integrated photonic devices.

6.
Opt Lett ; 45(18): 5012-5015, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32932440

RESUMEN

Titanium dioxide (TiO2) microring resonators (MRRs) with high quality factors (Qs) are demonstrated by using a new, to the best of our knowledge, bottom-up fabrication method. Pattern platforms with a T-shaped cross section are first defined by etching a thin top layer of silicon nitride and a thick bottom layer of silica and partially undercutting the silica. Then, TiO2 is deposited on the platforms to form the TiO2 waveguides and devices. TiO2 MRRs with different bending radii, waveguide widths, and gaps in the bus waveguide are fabricated and measured. The intrinsic Q(Qint) is achieved to be ∼1.1×105 at the telecommunication wavelengths, corresponding to a bend waveguide loss of 3.9 dB/cm while the compact MRR with a radius of 10 µm can still sustain a Qint of ∼105. These results not only unfold the feasibilities of the proposed bottom-up method for fabricating TiO2 waveguides and MRRs with high Qs and compact footprints but also suggest a new approach for fabricating waveguides in other materials, of which direct etching is not easily accessible.

7.
Opt Express ; 26(14): 18190-18201, 2018 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-30114099

RESUMEN

Mode-locked lasers with strong high order dispersion exhibit rich nonlinear dynamics. Here we numerically and experimentally demonstrate coexistence of dissipative soliton (DS) and stretched pulse (SP) in a dual-wavelength mode-locked Tm-doped fiber laser with strong third-order dispersion (TOD), where the DS and SP show completely different pulse duration and peak power. Wavelength-dependent feature of the net cavity group-velocity dispersion (GVD) leaded by the strong TOD plays a key role for the coexistence patterns. To our best knowledge, this is the first demonstration of the coexistence of different mode-locked pulse regimes with strong laser cavity TOD.

8.
Chin Med Sci J ; 33(3): 160-173, 2018 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-30266106

RESUMEN

Objective To analyze characteristics of high altitude pulmonary edema (HAPE) in Chinese patients.Methods We performed a retrospective study of 98 patients with HAPE. We reviewed the medical records and summarized the clinical, laboratory and imaging characteristics of these cases, and compared the results on admission with those determined before discharge.Results Forty-eight (49.0%) patients developed HAPE at the altitude of 2800 m to 3000 m. Ninty-five (96.9%) patients were man. Moist rales were audible from the both lungs, and moist rales over the right lung were clearer than those over the left lung in fourteen patients. The white blood cells [(12.83±5.55) versus (8.95±3.23) ×10 9/L, P=0.001)] as well as neutrophil counts [(11.34±3.81) versus (7.49±2.83)×10 9/L, P=0.001)] were higher, whereas the counts of other subsets of white blood cells were lower on admission than those after recovery (all P<0.05). Serum levels of alkaline phosphatase (115.8±37.6 versus 85.7±32.4 mmol/L, P=0.020), cholinesterase (7226.2±1631.8 versus 6285.3±1693.3 mmol/L, P=0.040), creatinine (85.2±17.1 versus75.1±12.8 mmol/L, P=0.021), uric acid (401.9±114.2 versus 326.0±154.3 mmol/L, P=0.041), and uric glucose (7.20±1.10 versus 5.51±1.11 mmol/L, P=0.001) were higher, but carbondioxide combining power (CO2CP, 26.7±4.4 versus 28.9±4.5 mmol/L, P=0.042) and serous calcium (2.32±0.13 versus 2.41±0.10 mmol/L, P=0.006) were lower on admission. Arterial blood gas results showed hypoxemia and respiratory alkalosis on admission. Conclusions In the present research, men were more susceptible to HAPE than women, and in the process of HAPE, the lesions of the right lung were more serious than those of the left lung. Some indicators of routine blood test and blood biochemistry of HAPE patients changed.


Asunto(s)
Altitud , Edema Pulmonar/diagnóstico por imagen , Edema Pulmonar/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Edema Pulmonar/sangre , Tibet , Tomografía Computarizada por Rayos X
9.
Artículo en Inglés | MEDLINE | ID: mdl-38986448

RESUMEN

The segmentation of atrial scars in LGE-MRI images has huge potential value for clinical diagnosis and subsequent treatment. In clinical practice, atrial scars are usually manually calibrated by experienced experts, which is time-consuming and prone to errors. However, automatic segmentation also faces difficulties due to myocardial scars' small size and variable shape. The present study introduces a dual branch network, incorporating edge attention, and deep supervision strategy. Edge attention is introduced to fully utilize the spatial relationship between the scar and the atrium. Besides, dense attention is embedded in bottom layer to solve feature disappearance. At the same time, deep supervision accelerates the convergence of the model and improves segmentation accuracy. The experiments were conducted on the 2022 atrial and scar segmentation challenge dataset. The results demonstrate that the proposed method has achieved superior performance.

10.
Chemosphere ; 357: 142048, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38641295

RESUMEN

The wide application of flexible polyurethane foam (FPUF) poses a giant challenge to human society in terms of fire prevention and environmental pollution. To solve this problem, the lignocellulose-based P-N flame retardant (LFPN) has been developed using mechanochemical methods. It was found that FPUF treated using LFPN exhibited good flame retardancy, but suffered from high smoke generation and toxicity. The hollow dodecahedral ZIF-67 has been used for smoke suppression catalysis, but the agglomeration phenomenon makes it inefficient. Hence, in this study, the adhesive properties of polydopamine (PDA) were utilized to assist the in-situ growth of ZIF-67. The results showed that the total smoke release rate of the treated FPUF was reduced by 40.5%. The toxic gases, such as carbon monoxide (CO), hydrogen cyanide, etc., also showed the same decreasing trend. What's more, the catalytic effect of ZIF-67 itself and the synergistic effect with LFPN gave FPUF great flame retardant and smoke inhibition properties. This novel FPUF provides a new reference for achieving smoke suppression and toxicity reduction.


Asunto(s)
Retardadores de Llama , Poliuretanos , Humo , Retardadores de Llama/toxicidad , Poliuretanos/química , Indoles/química , Incendios/prevención & control , Polímeros/química , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/química , Monóxido de Carbono/química , Catálisis , Imidazoles , Zeolitas
11.
Chemosphere ; 358: 142151, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38679169

RESUMEN

Herein, MXene-based composite aerogel (MXene-Fe2+ aerogel) are constructed by a one-step freeze-drying method, using Ti3C2Tx MXene layers as substrate material and ferrous ion (Fe2+) as crosslinking agent. With the aid of the Fe2+ induced Fenton reaction, the synthesized aerogels are used as the particle electrodes to remove phenol from wastewater with three-dimensional electrode technology. Combined with the dual roles of Fe2+ and the highly conductive MXene, the obtained particle electrode possesses extremely effective phenol degradation. The effects of experiment parameters such as Fe2+ to MXene ratio, particle electrode dosage, applied voltage, and initial pH of solution on the removal of phenol are discussed. At pH = 2.5, phenol with 50 mg/L of initial concentration can be completely removed within 50 min at 10 V with the particle electrode dosage of 0.56 g/L. Finally, the mechanism of degradation is explored. This work provides an effective way for phenol degradation by MXene-based aerogel, which has great potential for the degradation of other organic pollutants in wastewater.


Asunto(s)
Geles , Fenol , Eliminación de Residuos Líquidos , Aguas Residuales , Contaminantes Químicos del Agua , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Fenol/química , Geles/química , Eliminación de Residuos Líquidos/métodos , Hierro/química , Electrodos , Concentración de Iones de Hidrógeno , Iones/química , Compuestos Ferrosos/química , Titanio/química
12.
Nat Commun ; 15(1): 2330, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38485996

RESUMEN

Miniaturised optical spectrometers are attractive due to their small footprint, low weight, robustness and stability even in harsh environments such as space or industrial facilities. We report on a stationary-wave integrated Fourier-transform spectrometer featuring a measured optical bandwidth of 325 nm and a theoretical spectral resolution of 1.2 nm. We fabricate and test on lithium niobate-on-insulator to take full advantage of the platform, namely electro-optic modulation, broad transparency range and the low optical loss achieved thanks to matured fabrication techniques. We use the electro-optic effect and develop innovative layouts to overcome the undersampling limitations and improve the spectral resolution, thus providing a framework to enhance the performance of all devices sharing the same working principle. With our work, we add another important element to the portfolio of integrated lithium-niobate optical devices as our spectrometer can be combined with multiple other building blocks to realise functional, monolithic and compact photonic integrated circuits.

13.
mSystems ; 9(3): e0125723, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38349131

RESUMEN

Limosilactobacillus reuteri, a probiotic microbe instrumental to human health and sustainable food production, adapts to diverse environmental shifts via dynamic gene expression. We applied the independent component analysis (ICA) to 117 RNA-seq data sets to decode its transcriptional regulatory network (TRN), identifying 35 distinct signals that modulate specific gene sets. Our findings indicate that the ICA provides a qualitative advancement and captures nuanced relationships within gene clusters that other methods may miss. This study uncovers the fundamental properties of L. reuteri's TRN and deepens our understanding of its arginine metabolism and the co-regulation of riboflavin metabolism and fatty acid conversion. It also sheds light on conditions that regulate genes within a specific biosynthetic gene cluster and allows for the speculation of the potential role of isoprenoid biosynthesis in L. reuteri's adaptive response to environmental changes. By integrating transcriptomics and machine learning, we provide a system-level understanding of L. reuteri's response mechanism to environmental fluctuations, thus setting the stage for modeling the probiotic transcriptome for applications in microbial food production. IMPORTANCE: We have studied Limosilactobacillus reuteri, a beneficial probiotic microbe that plays a significant role in our health and production of sustainable foods, a type of foods that are nutritionally dense and healthier and have low-carbon emissions compared to traditional foods. Similar to how humans adapt their lifestyles to different environments, this microbe adjusts its behavior by modulating the expression of genes. We applied machine learning to analyze large-scale data sets on how these genes behave across diverse conditions. From this, we identified 35 unique patterns demonstrating how L. reuteri adjusts its genes based on 50 unique environmental conditions (such as various sugars, salts, microbial cocultures, human milk, and fruit juice). This research helps us understand better how L. reuteri functions, especially in processes like breaking down certain nutrients and adapting to stressful changes. More importantly, with our findings, we become closer to using this knowledge to improve how we produce more sustainable and healthier foods with the help of microbes.


Asunto(s)
Limosilactobacillus reuteri , Probióticos , Humanos , Limosilactobacillus reuteri/genética , Perfilación de la Expresión Génica , Transcriptoma/genética , Aprendizaje Automático
14.
Adv Sci (Weinh) ; 11(15): e2306229, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38342602

RESUMEN

Splicing factor polyglutamine binding protein-1 (PQBP1) is abundantly expressed in the central nervous system during development, and mutations in the gene cause intellectual disability. However, the roles of PQBP1 in cancer progression remain largely unknown. Here, it is shown that PQBP1 overexpression promotes tumor progression and indicates worse prognosis in ovarian cancer. Integrative analysis of spyCLIP-seq and RNA-seq data reveals that PQBP1 preferentially binds to exon regions and modulates exon skipping. Mechanistically, it is shown that PQBP1 regulates the splicing of genes related to the apoptotic signaling pathway, including BAX. PQBP1 promotes BAX exon 2 skipping to generate a truncated isoform that undergoes degradation by nonsense-mediated mRNA decay, thus making cancer cells resistant to apoptosis. In contrast, PQBP1 depletion or splice-switching antisense oligonucleotides promote exon 2 inclusion and thus increase BAX expression, leading to inhibition of tumor growth. Together, the results demonstrate an oncogenic role of PQBP1 in ovarian cancer and suggest that targeting the aberrant splicing mediated by PQBP1 has therapeutic potential in cancer treatment.


Asunto(s)
Discapacidad Intelectual , Neoplasias Ováricas , Femenino , Humanos , Proteína X Asociada a bcl-2/genética , Proteínas de Unión al ADN/genética , Discapacidad Intelectual/genética , Discapacidad Intelectual/patología , Neoplasias Ováricas/genética , Empalme del ARN/genética , Factores de Empalme de ARN/genética
15.
Cancer Res ; 83(21): 3650-3666, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37669142

RESUMEN

Alternative polyadenylation (APA) is emerging as a major mechanism of posttranscriptional regulation. APA can impact the development and progression of cancer, suggesting that the genetic determinants of APA might play an important role in regulating cancer risk. Here, we depicted a pan-cancer atlas of human APA quantitative trait loci (apaQTL), containing approximately 0.7 million apaQTLs across 32 cancer types. Systematic multiomics analyses indicated that cancer apaQTLs could contribute to APA regulation by altering poly(A) motifs, RNA-binding proteins (RBP), and chromatin regulatory elements and were preferentially enriched in genome-wide association studies (GWAS)-identified cancer susceptibility loci. Moreover, apaQTL-related genes (aGene) were broadly related to cancer signaling pathways, high mutational burden, immune infiltration, and drug response, implicating their potential as therapeutic targets. Furthermore, apaQTLs were mapped in Chinese colorectal cancer tumor tissues and then screened for functional apaQTLs associated with colorectal cancer risk in 17,789 cases and 19,951 controls using GWAS-ChIP data, with independent validation in a large-scale population consisting of 6,024 cases and 10,022 controls. A multi-ancestry-associated apaQTL variant rs1020670 with a C>G change in DNM1L was identified, and the G allele contributed to an increased risk of colorectal cancer. Mechanistically, the risk variant promoted aberrant APA and facilitated higher usage of DNM1L proximal poly(A) sites mediated by the RBP CSTF2T, which led to higher expression of DNM1L with a short 3'UTR. This stabilized DNM1L to upregulate its expression, provoking colorectal cancer cell proliferation. Collectively, these findings generate a resource for understanding APA regulation and the genetic basis of human cancers, providing insights into cancer etiology. SIGNIFICANCE: Cancer risk is mediated by alternative polyadenylation quantitative trait loci, including the rs1020670-G variant that promotes alternative polyadenylation of DNM1L and increases colorectal cancer risk.


Asunto(s)
Neoplasias Colorrectales , Estudio de Asociación del Genoma Completo , Humanos , Poliadenilación/genética , Regulación de la Expresión Génica , Sitios de Carácter Cuantitativo , Neoplasias Colorrectales/genética , Regiones no Traducidas 3'/genética
16.
Nat Commun ; 14(1): 7900, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38036550

RESUMEN

Left ventricular regional wall thickness (LVRWT) is an independent predictor of morbidity and mortality in cardiovascular diseases (CVDs). To identify specific genetic influences on individual LVRWT, we established a novel deep learning algorithm to calculate 12 LVRWTs accurately in 42,194 individuals from the UK Biobank with cardiac magnetic resonance (CMR) imaging. Genome-wide association studies of CMR-derived 12 LVRWTs identified 72 significant genetic loci associated with at least one LVRWT phenotype (P < 5 × 10-8), which were revealed to actively participate in heart development and contraction pathways. Significant causal relationships were observed between the LVRWT traits and hypertrophic cardiomyopathy (HCM) using genetic correlation and Mendelian randomization analyses (P < 0.01). The polygenic risk score of inferoseptal LVRWT at end systole exhibited a notable association with incident HCM, facilitating the identification of high-risk individuals. The findings yield insights into the genetic determinants of LVRWT phenotypes and shed light on the biological basis for HCM etiology.


Asunto(s)
Cardiomiopatía Hipertrófica , Estudio de Asociación del Genoma Completo , Humanos , Cardiomiopatía Hipertrófica/diagnóstico por imagen , Cardiomiopatía Hipertrófica/genética , Corazón , Ventrículos Cardíacos/patología , Fenotipo
17.
Chemosphere ; 290: 133265, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34914951

RESUMEN

Improper disposal of chlorinated solvents such as trichloroethylene (TCE) and its stabilizer 1,4-dioxane has resulted in extensive contamination in soils and groundwater. Oxidative degradation of these contaminants by strong oxidants has been proposed recently as a remediation strategy, but specific mechanisms and degradation efficiencies are still poorly understood, especially in commingled systems. In this study, a reduced iron-bearing clay (RIC), nontronite (rNAu-2), was oxygenated to produce hydroxyl radicals (•OH) for degradation of TCE and 1,4-dioxane under circumneutral and dark conditions. Results showed that TCE and 1,4-dioxane could be effectively degraded during oxygenation of rNAu-2 in both single and commingled systems. Compared with the single compound system, the degradation rates and efficiencies of TCE and 1,4-dioxane decreased in the commingled system. The negative effect was more significant for TCE than 1,4-dioxane. The commingled TCE and 1,4-dioxane impacted the degradation pattern of each other, due to their difference in •OH scavenging efficiency, surface affinity to rNAu-2 and solubility. Moreover, solution pH, buffer type, rNAu-2 dosage, and dissolved organic matter all affected •OH production and contaminant degradation efficiency. Our findings provide new insights for investigating the natural attenuation of commingled chlorinated solvents and 1,4-dioxane by RIC in redox-fluctuating environments and offer guidance for developing possible in-situ remediation strategies.


Asunto(s)
Agua Subterránea , Tricloroetileno , Contaminantes Químicos del Agua , Arcilla , Dioxanos , Materia Orgánica Disuelta , Radical Hidroxilo , Minerales , Oxidación-Reducción , Estrés Oxidativo , Tricloroetileno/análisis , Contaminantes Químicos del Agua/análisis
18.
Artículo en Inglés | MEDLINE | ID: mdl-36142106

RESUMEN

The microbial remediation technology had great potential and attracted attention to total petroleum hydrocarbon pollution (TPH) remediation, but its efficiency is limited by its application in the field. In this study, a new TPH-degrading strain, TDYN1, was isolated from contaminated oil soil in Dagang Oilfield in Tianjin, China, and identified as Falsochrobactrum sp. by 16S rRNA sequence analysis. The physiological characterization of the isolate was observed. The orthogonal experiment was carried out for the optimum degradation conditions to improve its biodegradation efficiency. The strain was the gram-stain-negative, short rod-shaped, non-spore-forming, designated Falsochrobactrum tianjinense sp. nov (strain TDYN1); it had 3.51 Mb, and the DNA G + C content of the strain was 56.0%. The degradation rate of TDYN1 was 69.95% after 7 days of culture in optimal degradation conditions (temperature = 30 °C, pH = 8, salinity = 10 g L-1, petroleum concentration = 1 g L-1, and the inoculation dose of strain TDYN1 = 6%) and also reached more than 30% under other relatively extreme conditions. It suggested that the TDYN1 has great potential for TPH remediation in the soils of North China.


Asunto(s)
Petróleo , Contaminantes del Suelo , Bacterias/genética , Biodegradación Ambiental , Hidrocarburos/metabolismo , Petróleo/análisis , Filogenia , ARN Ribosómico 16S/genética , Suelo/química , Microbiología del Suelo , Contaminantes del Suelo/análisis
19.
Front Microbiol ; 13: 844663, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35651488

RESUMEN

Nitrous oxide (N2O) is a powerful greenhouse gas and the predominant stratospheric ozone-depleting substance. Soil is a major source of N2O but remains largely uncertain due to the complicated processes of nitrification and denitrification performed by various groups of microbes such as bacteria, fungi, and archaea. We used incubation experiments to measure the total fungal, archaeal, and bacterial N2O production potential and the microbial functional genes in soils along 3,000 km Chinese grassland transect, including meadow steppe, typical steppe, desert steppe, alpine meadow, and alpine steppe. The results indicated that fungi, archaea, and bacteria contributed 25, 34, and 19% to nitrification and 46, 29, and 15% to denitrification, respectively. The AOA and AOB genes were notably correlated with the total nitrification enzyme activity (TNEA), whereas both narG and nirK genes were significantly correlated with total denitrification enzyme activity (TDEA) at p < 0.01. The correlations between AOA and ANEA (archaeal nitrification enzyme activity), AOB and BNEA (bacterial nitrification enzyme activity), and narG, nirK, and BDEA (bacterial denitrification enzyme activity) showed higher coefficients than those between the functional genes and TNEA/TDEA. The structural equation modeling (SEM) results showed that fungi are dominant in N2O production processes, followed by archaea in the northern Chinese grasslands. Our findings indicate that the microbial functional genes are powerful predictors of the N2O production potential, after distinguishing bacterial, fungal, and archaeal processes. The key variables of N2O production and the nitrogen (N) cycle depend on the dominant microbial functional groups in the N-cycle in soils.

20.
Natl Sci Rev ; 9(10): nwac128, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36196117

RESUMEN

Mineral-microbe interactions play important roles in environmental change, biogeochemical cycling of elements and formation of ore deposits. Minerals provide both beneficial (physical and chemical protection, nutrients, and energy) and detrimental (toxic substances and oxidative pressure) effects to microbes, resulting in mineral-specific microbial colonization. Microbes impact dissolution, transformation and precipitation of minerals through their activity, resulting in either genetically controlled or metabolism-induced biomineralization. Through these interactions, minerals and microbes co-evolve through Earth history. Mineral-microbe interactions typically occur at microscopic scale but the effect is often manifested at global scale. Despite advances achieved through decades of research, major questions remain. Four areas are identified for future research: integrating mineral and microbial ecology, establishing mineral biosignatures, linking laboratory mechanistic investigation to field observation, and manipulating mineral-microbe interactions for the benefit of humankind.

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