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Understanding how microbial lipidomes adapt to environmental and nutrient stress is crucial for comprehending microbial survival and functionality. Certain anaerobic bacteria can synthesize glycerolipids with ether/ester bonds, yet the complexities of their lipidome remodeling under varying physicochemical and nutritional conditions remain largely unexplored. In this study, we thoroughly examined the lipidome adaptations of Desulfatibacillum alkenivorans strain PF2803T, a mesophilic anaerobic sulfate-reducing bacterium known for its high proportions of alkylglycerol ether lipids in its membrane, under various cultivation conditions including temperature, pH, salinity, and ammonium and phosphorous concentrations. Employing an extensive analytical and computational lipidomic methodology, we identified an assemblage of nearly 400 distinct lipids, including a range of glycerol ether/ester lipids with various polar head groups. Information theory-based analysis revealed that temperature fluctuations and phosphate scarcity profoundly influenced the lipidome's composition, leading to an enhanced diversity and specificity of novel lipids. Notably, phosphorous limitation led to the biosynthesis of novel glucuronosylglycerols and sulfur-containing aminolipids, termed butyramide cysteine glycerols, featuring various ether/ester bonds. This suggests a novel adaptive strategy for anaerobic heterotrophs to thrive under phosphorus-depleted conditions, characterized by a diverse array of nitrogen- and sulfur-containing polar head groups, moving beyond a reliance on conventional nonphospholipid types.
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Lipidómica , Nitrógeno , Fósforo , Azufre , Fósforo/metabolismo , Azufre/metabolismo , Nitrógeno/metabolismo , Adaptación Fisiológica , Sulfatos/metabolismo , Bacterias Anaerobias/metabolismo , AnaerobiosisRESUMEN
Carbon nanotubes (CNTs) are a promising material for humidity sensors and wearable electronics due to their solution capability, good flexibility, and high conductivity. However, the performance of CNT-based humidity sensors is limited by their low sensitivity and slow response. Herein CNTs and hydrophilic polymers were mixed to form a composite. The hydrophilicity of the polymers and the network structure of the CNTs empowered the humidity sensors with a high response of 171% and a fast response/recovery time of 23 s/10 s. Owing to the sticky and flexible polymers, the humidity sensors showed strong adhesion to the PET substrate and exhibited outstanding bending durability. Furthermore, the flexible humidity sensor was applied to monitor human breathing and detect finger movements and handshaking.
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MicroRNAs (miRNAs) are small non-coding RNAs, and they bind to complementary sequences in the three prime untranslated regions (3' UTRs) of target mRNA transcripts, thereby inhibiting mRNA translation or promoting mRNA degradation. Excessive reactive oxygen species (ROS) can cause cell-damaging effects through oxidative modification of macromolecules leading to their inappropriate functions. Such oxidative modification is related to cancers, aging, and neurodegenerative and cardiovascular diseases. Here we report that miRNAs can be oxidatively modified by ROS. We identified that miR-184 upon oxidative modification associates with the 3' UTRs of Bcl-xL and Bcl-w that are not its native targets. The mismatch of oxidized miR-184 with Bcl-xL and Bcl-w is involved in the initiation of apoptosis in the study with rat heart cell line H9c2 and mouse models. Our results reveal a model of ROS in regulating cellular events by oxidatively modifying miRNA.
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Regiones no Traducidas 3'/genética , MicroARNs/metabolismo , Proteínas/genética , Especies Reactivas de Oxígeno/metabolismo , Proteína bcl-X/genética , Animales , Apoptosis/genética , Proteínas Reguladoras de la Apoptosis , Línea Celular , Masculino , Ratones , Ratones Endogámicos C57BL , MicroARNs/genética , Miocardio/citología , Miocardio/metabolismo , Oxidación-Reducción , Interferencia de ARN , ARN Interferente Pequeño , RatasRESUMEN
In this study, a water-soluble polysaccharide from Eucommia folium was extracted by hot water and purified using Sephadex G-200 gel columns. The results showed that the purified fraction (EFP) has a molecular weight of 9.98 × 105 Da and consisted of rhamnose, arabinose, galactose, glucose, mannose, xylose, galacturonic acid, and glucuronic acid (molar ratio: 0.226: 1.739: 2.183: 1: 0.155: 0.321: 0.358: 0.047). The combination of infrared spectroscopy and NMR analysis proved that EFP is an acidic polysaccharide whose main chain consists of α-L-Araf-(1 â , â 3,5)-α-Araf-(1 â , â 3)-ß-Galp-(1 â , â 3,6)-ß-Glcp-(1 â , â 2)-α-D-Manp-(1 â , â 4)-α-GalpA-(1 â , â 2,4)-α-Rhap-(1 â . In addition, the in vivo antitumoral activity of EFP was studied using a H22 tumor-bearing mice model. EFP effectively inhibited tumor growth in mice following intragastric administration. By Combining with the results of the apoptosis assay and JC-1 staining analysis, we confirmed that EFP induces apoptosis through the mitochondrial pathway. Furthermore, cell cycle analysis demonstrated that EFP blocks the cell cycle at S phase.
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Polisacáridos , Agua , Ratones , Animales , Polisacáridos/química , Galactosa , Ramnosa , Peso MolecularRESUMEN
Flexible transparent electrodes for touch panels, solar cells, and wearable electronics are in great demand in recent years, and the silver nanowire (AgNW) flexible transparent electrode (FTE) is among the top candidates due to its excellent light transmittance and flexibility and the highest conductivity of silver among all metals. However, the conductivity of an AgNWs network has long been limited by the large contact resistance. Here we show a room-temperature solution process to tackle the challenge by nanojoining AgNWs with two-dimensional graphene oxide (GO). The conductivity of the AgNWs network is improved 18 times due to the enhanced junctions between AgNWs by the coated GOs, and the AgNW-GO FTE exhibits a low sheet resistance of 23 Ohm sq-1and 88% light transmittance. It is stable under high temperature and current and their flexibility is intact after 1000 cycles of bending. Measurements of a bifunctional electrochromic device shows the high performance of the AgNW-GO FTE as a FTE.
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With astonishing and rapid development in China since the Reform and Opening-up in 1978, serious air pollution has become a great challenge. A better understanding of the response of PM2.5 pollution to socioeconomic development after the Reform and Opening-up policy is benefit for pollution control. However, heterogeneous influences of biophysical and socioeconomic activities on PM2.5 pollution pose great challenges in statistical simulation of PM2.5. Few statistical model regards aerosol species as the explanatory variables for heterogeneous formation mechanism to retrieve PM2.5 concentration. In this research, monthly PM2.5 concentration in China during 1980-2020 was reconstructed by a novel statistical strategy considering aerosol components (AC-RF). Three cross-validation (CV) methods, sample-based CV, spatial-based CV and temporal-based CV results indicated satisfactory performance of AC-RF model with correlation coefficient (R) of 0.92, 0.90, 0.86, respectively. A three-stage concluded on PM2.5 concentration annual variation in China was drawn as followed: Before 2000, PM2.5 level in China represented smooth evolution and mainly influenced by natural events with polluted region locating in Xinjiang province, North China and Central China. Since 2000, PM2.5 concentration increased to high level in the context of rapid socioeconomic development. Severe air pollution covered Jing-Jin-Ji agglomeration, Central China and Sichuan Basin. During 2012-2020, PM2.5 declined and polluted region shrank, which was benefited by the strictest-ever air pollution control measures. Based on aerosol components analysis, sulfate aerosol exhibited the most significant increase trend in recent 40 years and black aerosol variation is the most closely related to PM2.5 pollution. In conclusion, unsustainable development is the culprit for air quality deterioration. Strict and continuous air pollution control strategies are effective for air quality improvement.
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Contaminantes Atmosféricos , Material Particulado , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , China , Monitoreo del Ambiente/métodos , Material Particulado/análisis , Sulfatos/análisisRESUMEN
PURPOSE: A Killian-Jamieson diverticulum (KJD) may be mistaken for a thyroid nodule on ultrasound (US). The purpose of this retrospective study was to search for specific US features that would help differentiate between KJD and thyroid nodules. METHODS: A total of 12 patients with KJD who had undergone an US examination of the neck were identified. The size, shape, boundary, echopattern, location, color flow signals on color Doppler US of KJD and the relationship between the lesion and esophageal wall were analyzed. The change of size, shape and internal echotexture were also observed when the lesion was compressed with the probe and when the patient was asked to drink water. RESULTS: All KJD were confirmed by barium esophagography. All KJD were posterior to the left thyroid lobe on US, and were associated with a semicircular hypoechoic anterior wall. The internal echotexture was heterogeneous. In eight cases, the connection to the esophageal wall was seen. When compressing with the US probe or when the patients swallowed water, the size, shape or internal echotexture of the lesion changed. CONCLUSION: The specific criteria for US diagnosis of KJD included the connection to the esophageal wall and the fact that the internal echotexture, shape and size of KJD changed in real-time when the patient swallowed water or when the lesion was compressed with the transducer.
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Divertículo de Zenker/diagnóstico por imagen , Adulto , Diagnóstico Diferencial , Esófago/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Nódulo Tiroideo/diagnóstico por imagen , UltrasonografíaRESUMEN
Severe tropospheric O3 pollution has swept across China in recent years. Consequently, investigation of tropospheric O3 concentration influencing mechanism is of significance for O3 pollution control in China. Previous studies have rarely detected combined impacts of natural factors and anthropogenic activities behind tropospheric O3 concentration in China at a national scale. Moreover, there is significant spatiotemporal heterogeneity of O3 pollution distribution in China due to the temporal and regional differences of socioeconomic and natural environmental condition in the vast territory. The targeted O3 control recommendations for different regions and seasons should be put forward in terms of the spatiotemporal heterogeneity of O3 concentration determinants. In this context, a three-level regression model integrating multi-scale biophysical and socioeconomic variables was proposed to explore the determinants of O3 pollution in China. The results showed that the tropospheric O3 concentration in the eastern and southeastern regions of China was strongly affected by meteorological conditions. In contrast, tropospheric O3 pollution concentrated in inland areas mainly depended on the emission intensity from anthropogenic sources.
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Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , China , Monitoreo del Ambiente , Análisis Multinivel , Estaciones del Año , Factores SocioeconómicosRESUMEN
Smoking is associated with an increased risk of respiratory diseases, including lung cancer and asthma. However, the mechanisms or diagnostic markers for smoking-related diseases remain largely unknown. Here we investigated the role of cigarette smoke condensate (CSC) in the regulation of human bronchial epithelial cell (BEAS-2B) behavior. We found that exposure to CSC significantly inhibited BEAS-2B cell viability, impaired cell morphology, induced cell apoptosis, triggered oxidative damage, and promoted inflammatory response, which suggests a deleterious effect of CSC on bronchial epithelial cells. In addition, CSC markedly altered the expression of apoptosis-associated protein factors, including p21, soluble tumor necrosis factor receptor 1, and Fas ligand. In sum, our study identified a panel of novel protein factors that may mediate the actions of CSC on bronchial epithelial cells and have a predictive value for the development and progression of smoking-related diseases, thus providing insights into the development of potential diagnostic and therapeutic strategies against these diseases.
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Proteínas Reguladoras de la Apoptosis/biosíntesis , Bronquios/metabolismo , Fumar Cigarrillos/metabolismo , Células Epiteliales/metabolismo , Regulación de la Expresión Génica , Estrés Oxidativo , Bronquios/patología , Línea Celular , Fumar Cigarrillos/patología , Células Epiteliales/patología , HumanosRESUMEN
A novel high-throughput method was established for rapid screening of a large numbers of Aspergillus fumigatus (A. fumigatus) mutants with high chitosanase production under acidic culture condition by exploiting the fact that iodine can be used as the indicator to stain chitosan but is ineffective for chitooligosaccharides. The mutant population was generated by irradiating A. fumigatus CICC 2434 with Co(60)-γ rays. Mutants were cultured on acidic plates containing colloidal chitosan and preliminary screened according to diameter of haloes formed around colonies. Then, chitosanase production of the isolates were verified by dinitrosalicylic acid assay. Lastly, molecular masses on enzymolysis products of isolated mutants were rapidly compared by aniline blue plate assay. Using this method, the mutant strain Co-8 was selected, which had chitosanase activity of 24.87 U/mL (increased by 369.2 % as compared to that of its parental strain).Taking together, the method is easy, efficient and particularly suited to rapid screen acidophilic fungal strains with high chitosanase-production.
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Ácidos/química , Aspergillus fumigatus/enzimología , Aspergillus fumigatus/aislamiento & purificación , Glicósido Hidrolasas/metabolismo , Ensayos Analíticos de Alto Rendimiento/métodos , Aspergillus fumigatus/genética , Aspergillus fumigatus/efectos de la radiación , Medios de Cultivo/química , Glicósido Hidrolasas/genética , Yodo/química , Peso Molecular , MutaciónRESUMEN
A problem frequently occurring in making some kinds of wines, particularly Vitis quinquangularis Rehd wine, is the presence of malic acid at high concentrations, which is detrimental to the quality of wines. Thus, there is a need of the ways for effectively reducing the malic acid levels in wine. This study aimed to generate shuffled fusants of Schizosaccharomyces pombe with enhanced deacidification activity for reducing the excessive malic acid content in wine. Sz. pombe CGMCC 2.1628 was used as the original strain. The starting mutant population was generated by UV treatment. The mutants with higher deacidification activity were selected and subjected to recursive protoplast fusion. The resulting fusants were screened by using the indicator of malic acid concentration of fermentation supernatants on 96-well microtitre plates, measured with bromocresol green. After three rounds of genome shuffling, the best-performing fusant, named GS3-1, was obtained. Its deacidification activity (consumed 4.78 g/l malic acid within 10 days) was increased by 225.2% as compared to that of original strain. In the Vitis quinquangularis Rehd wine fermentation test, GS3-1 consumed 4.0 g/l malic acid during the whole cycle of fermentation, providing up to 185.7% improvement in malic acid consumption compared with that of the original strain. This study shows that GS3-1 has great potential for improving the quality of Vitis quinquangularis Rehd wine.
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Genoma Fúngico , Malatos/metabolismo , Schizosaccharomyces/genética , Vino , Fermentación , Recombinación Genética , Schizosaccharomyces/metabolismo , Vitis/químicaRESUMEN
Copper nanowire transparent electrodes have received increasing interest due to the low price and nearly equal electrical conductivity compared with other TEs based on silver nanowires and indium tin oxide (ITO). However, a post-treatment at high temperature in an inert atmosphere or a vacuum environment was necessary to improve the conductivity of Cu NW TEs due to the easy oxidation of copper in air atmosphere, which greatly cancelled out the low price advantage of Cu NWs. Here, a high intensity pulsed light technique was introduced to sinter and simultaneously deoxygenate these Cu NWs into a highly conductive network at room temperature in air. The strong light absorption capacity of Cu NWs enabled the welding of the nanowires at contact spots, as well as the removal of the thin layer of residual organic compounds, oxides and hydroxide of copper even in air. The Cu NW TE with a sheet resistance of 22.9 Ohm sq(-1) and a transparency of 81.8% at 550 nm has been successfully fabricated within only 6 milliseconds exposure treatment, which is superior to other films treated at high temperature in a hydrogen atmosphere. The HIPL process was simple, convenient and fast to fabricate easily oxidized Cu NW TEs in large scale in an air atmosphere, which will largely extend the application of cheap Cu NW TEs.
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MicroRNAs (miRNAs) are small, single-stranded, noncoding RNAs that function as negative regulators of gene expression. They are transcribed from endogenous DNA and form hairpin structures (termed as pre-miRNAs) that are processed to form mature miRNAs. It remains largely unknown as to the molecular consequences of the natural genetic variation in pre-miRNAs. Here, we report that an AâG polymorphism (rs71428439) is located in Homo sapiens miR-149 stem-loop region. This polymorphism results in a change in the structure of the miR-149 precursor. Our results showed that the genotype distribution of this polymorphism in myocardial infarction cases was significantly different from that in the control subjects. We examined the biological significance of this polymorphism on the production of mature miR-149, and we observed that the G-allelic miR-149 precursor displayed a lower production of mature miR-149 compared with the A-allelic one. Further investigations disclosed that miR-149 could withstand mitochondrial fission and apoptosis through targeting the pro-apoptotic factor p53-up-regulated modulator of apoptosis (Puma). Enforced expression of miR-149 promoted cell survival, whereas knockdown of miR-149 rendered cells to be sensitive to apoptotic stimulation. Intriguingly, the A to G variation led pre-miR-149 to elicit an attenuated effect on the inhibition of mitochondrial fission and apoptosis. Finally, this polymorphism exerts its influence on cardiac function in the mouse model of myocardial infarction. These data suggest that this polymorphism in the miR-149 precursor may result in important phenotypic traits of myocardial infarction. Our findings warrant further investigations on the relationship between miR-149 polymorphism and myocardial infarction.
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Proteínas Reguladoras de la Apoptosis/metabolismo , Apoptosis , MicroARNs/genética , Infarto del Miocardio/genética , Polimorfismo de Nucleótido Simple , Proteínas Proto-Oncogénicas/metabolismo , Adulto , Anciano , Animales , Enfermedades Cardiovasculares/metabolismo , Caspasa 3/metabolismo , Células Cultivadas , Femenino , Regulación de la Expresión Génica , Predisposición Genética a la Enfermedad , Vectores Genéticos , Genotipo , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Miocitos Cardíacos/citología , Fenotipo , Interferencia de ARNRESUMEN
Polycyclic aromatic hydrocarbons (PAHs) were analyzed for surface sediments and a sediment core from the Yellow River-dominated margin. The concentration of 16 USEPA priority PAHs in surface sediments ranged from 5.6 to 175.4 ng g(-1) dry weight sediment (dws) with a mean of 49.1 ng g(-1) dws. From 1930 to 2011, the distribution of PAHs (37.2 to 210.6 ng g(-1) dws) was consistent with the socioeconomic development of China. The PAHs' concentration peaked in 1964 and 1986, corresponding to the rapid economic growth in China (1958-1965) and the initiation of the "Reform and Open" policy in 1978, respectively. The applications of molecular diagnostic ratios and principal component analysis suggest that PAHs are predominantly produced by the coal and biomass combustion, whereas the contribution of petroleum combustions slightly increased after the 1970s, synchronous with an increasing usage of oil and gas in China.
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Monitoreo del Ambiente , Sedimentos Geológicos/química , Hidrocarburos Policíclicos Aromáticos/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , China , Humanos , Petróleo/toxicidad , Hidrocarburos Policíclicos Aromáticos/química , Análisis de Componente Principal , Ríos/química , Contaminantes Químicos del Agua/químicaRESUMEN
OBJECTIVE: To investigate the prevalence, clinical characteristics, treatment, and prognosis of neonatal respiratory failure (NRF) in Huai'an, Jiangsu Province, China, in 2010. METHODS: The clinical data of all NRF cases in the hospitals of Huai'an in 2010 were prospectively collected and analyzed using descriptive epidemiological methods. RESULTS: Among 60,986 live births in Huai'an in 2010, there were 556 (0.91%) cases of NRF. The average birth weight of newborns with NRF was 2,433±789 g, with 53.8% determined as low birth weight and 64.1% as preterm. The major causes of NRF were respiratory distress syndrome, pneumonia, asphyxia, sepsis, and pulmonary hemorrhage. Among the newborns with NRF, 23.7% were accompanied by certain birth defects. Fourteen percent of newborns with NRF received pulmonary surfactant (PS) therapy, and the median time of the first dose of PS was 5 hours (range: 0-51 hours). Nasal continuous positive airway pressure treatment, conventional mechanical ventilation, and high-frequency ventilation were used in 67.9%, 33.3%, and 13.7% of patients, respectively. The cure and improvement rate of NRF patients was 73.9% (411/556), and the mortality rate was 22.5% (125/556). The average hospitalization expenses were 9,270 (range: 196-38182) Yuan. CONCLUSIONS: High morbidity, high mortality and high medical costs make NRF a serious challenge in Huai'an. It is essential to improve the quality of perinatal care and develop new techniques and new models in neonatal respiratory therapy in order to reduce the morbidity and mortality of NRF.
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Insuficiencia Respiratoria/epidemiología , China/epidemiología , Femenino , Humanos , Recién Nacido , Masculino , Surfactantes Pulmonares/uso terapéutico , Respiración Artificial , Insuficiencia Respiratoria/mortalidad , Insuficiencia Respiratoria/terapia , Factores de Tiempo , Insuficiencia del TratamientoRESUMEN
Using KOH-modified wheat straw as the precursor, wheat straw biochar was produced through carbonization at 500 °C. Subsequently, a synthetic material containing nano-zero-valent iron (nZVI) was prepared via liquid phase reduction (nZVI-WSPC). To enhance its properties, chitosan (CTS) was used by crosslinking to form the new adsorbent named CTS@nZVI-WSPC. The impact of CTS on parameters such as mass ratio, initial pH value, and adsorbent dosage on the adsorption efficiency of Cr(VI) in solution was investigated through one-factor experiments. Isotherm adsorption and thermodynamic analysis demonstrated that the adsorption of Cr(VI) by CTS@nZVI-WSPC conforms to the Langmuir model, with a maximum adsorption capacity of 147.93 mg/g, and the adsorption process is endothermic. Kinetic analysis revealed that the adsorption process follows a pseudo-second-order kinetic model. The adsorption mechanism, as elucidated by SEM, FTIR, XPS, and XRD, suggests that the process may involve multiple mechanisms, including pore adsorption, electrostatic adsorption, chemical reduction, and surface chelation. The adsorption capacity of Cr(VI) by CTS@nZVI-WSPC remains high after five cycles. The adsorbent is simple to operate, economical, efficient, and reusable, making it a promising candidate for the treatment of Cr(VI) in water.
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Microbial lipids, used as taxonomic markers and physiological indicators, have mainly been studied through cultivation. However, this approach is limited due to the scarcity of cultures of environmental microbes, thereby restricting insights into the diversity of lipids and their ecological roles. Addressing this limitation, here we apply metalipidomics combined with metagenomics in the Black Sea, classifying and tentatively identifying 1623 lipid-like species across 18 lipid classes. We discovered over 200 novel, abundant, and structurally diverse sphingolipids in euxinic waters, including unique 1-deoxysphingolipids with long-chain fatty acids and sulfur-containing groups. Sphingolipids were thought to be rare in bacteria and their molecular and ecological functions in bacterial membranes remain elusive. However, genomic analysis focused on sphingolipid biosynthesis genes revealed that members of 38 bacterial phyla in the Black Sea can synthesize sphingolipids, representing a fourfold increase from previously known capabilities and accounting for up to 25% of the microbial community. These sphingolipids appear to be involved in oxidative stress response, cell wall remodeling and are associated with the metabolism of nitrogen-containing molecules. Our findings underscore the effectiveness of multi-omics approaches in exploring microbial chemical ecology.
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The symbiont Ca. Nanohaloarchaeum antarcticus is obligately dependent on its host Halorubrum lacusprofundi for lipids and other metabolites due to its lack of certain biosynthetic genes. However, it remains unclear which specific lipids or metabolites are acquired from its host, and how the host responds to infection. Here, we explored the lipidome dynamics of the Ca. Nha. antarcticus - Hrr. lacusprofundi symbiotic relationship during co-cultivation. By using a comprehensive untargeted lipidomic methodology, our study reveals that Ca. Nha. antarcticus selectively recruits 110 lipid species from its host, i.e., nearly two-thirds of the total number of host lipids. Lipid profiles of co-cultures displayed shifts in abundances of bacterioruberins and menaquinones and changes in degree of bilayer-forming glycerolipid unsaturation. This likely results in increased membrane fluidity and improved resistance to membrane disruptions, consistent with compensation for higher metabolic load and mechanical stress on host membranes when in contact with Ca. Nha. antarcticus cells. Notably, our findings differ from previous observations of other DPANN symbiont-host systems, where no differences in lipidome composition were reported. Altogether, our work emphasizes the strength of employing untargeted lipidomics approaches to provide details into the dynamics underlying a DPANN symbiont-host system.
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Lipidómica , Simbiosis , Halorubrum/metabolismo , Metabolismo de los Lípidos , Nanoarchaeota/metabolismo , Lípidos/químicaRESUMEN
Fossil epifoliar fungi are valuable indicators of paleoenvironment and paleoecology. The Meliolaceae, members of which typically inhabit the surface of living plants as biotrophs or pathogens, is one of the largest groups of epifoliar fungi. In this study, we report a novel fossil species of Meliolinites Selkirk (fossil Meliolaceae), Meliolinites tengchongensis, on the lower epidermis of compressed fossil Rhodoleia (Hamamelidaceae) leaves from the Upper Pliocene Mangbang Formation of Tengchong, Yunnan, southwestern China. Meliolinites tengchongensis is characterized by web-like, superficial, brown to dark brown, septate, and branching mycelia bearing 2-celled appressoria and unicellular phialides. The fungal colonies also include ellipsoidal, 5-celled, 4-septate ascospores and dark brown perithecia with suborbicular outline and verrucose surface. The well-preserved vegetative and reproductive organs help us to explore the potential disease process of the new fossil species. Besides, the presence of fungal remains indicates that the fungal taxon might have maintained its host preference since at least the Late Pliocene. Furthermore, the occurrence of both fossil fungi and their host plants in Tengchong indicate a subtropical-tropical, warm, and humid climate during the Late Pliocene, whereas the distribution pattern of the fungi on the host leaves suggests that Rhodoleia may have been a part of the middle-upper canopies in the Tengchong Late Pliocene multilayered forest.
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Fósiles , Hojas de la Planta , Hojas de la Planta/microbiología , China , Ascomicetos/clasificación , Ascomicetos/aislamiento & purificación , Esporas FúngicasRESUMEN
BACKGROUND: Within the normal range, elevated alanine aminotransferase (ALT) levels are associated with an increased risk of metabolic dysfunction-associated fatty liver disease (MAFLD). AIM: To investigate the associations between repeated high-normal ALT measurements and the risk of new-onset MAFLD prospectively. METHODS: A cohort of 3553 participants followed for four consecutive health examinations over 4 years was selected. The incidence rate, cumulative times, and equally and unequally weighted cumulative effects of excess high-normal ALT levels (ehALT) were measured. Cox proportional hazards regression was used to analyse the association between the cumulative effects of ehALT and the risk of new-onset MAFLD. RESULTS: A total of 83.13% of participants with MAFLD had normal ALT levels. The incidence rate of MAFLD showed a linear increasing trend in the cumulative ehALT group. Compared with those in the low-normal ALT group, the multivariate adjusted hazard ratios of the equally and unequally weighted cumulative effects of ehALT were 1.651 [95% confidence interval (CI): 1.199-2.273] and 1.535 (95%CI: 1.119-2.106) in the third quartile and 1.616 (95%CI: 1.162-2.246) and 1.580 (95%CI: 1.155-2.162) in the fourth quartile, respectively. CONCLUSION: Most participants with MAFLD had normal ALT levels. Long-term high-normal ALT levels were associated with a cumulative increased risk of new-onset MAFLD.