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BACKGROUND: The biosynthesis of human milk oligosaccharides (HMOs) using several microbial systems has garnered considerable interest for their value in pharmaceutics and food industries. 2'-Fucosyllactose (2'-FL), the most abundant oligosaccharide in HMOs, is usually produced using chemical synthesis with a complex and toxic process. Recombinant E. coli strains have been constructed by metabolic engineering strategies to produce 2'-FL, but the low stoichiometric yields (2'-FL/glucose or glycerol) are still far from meeting the requirements of industrial production. The sufficient carbon flux for 2'-FL biosynthesis is a major challenge. As such, it is of great significance for the construction of recombinant strains with a high stoichiometric yield. RESULTS: In the present study, we designed a 2'-FL biosynthesis pathway from fructose with a theoretical stoichiometric yield of 0.5 mol 2'-FL/mol fructose. The biosynthesis of 2'-FL involves five key enzymes: phosphomannomutase (ManB), mannose-1-phosphate guanylytransferase (ManC), GDP-D-mannose 4,6-dehydratase (Gmd), and GDP-L-fucose synthase (WcaG), and α-1,2-fucosyltransferase (FucT). Based on starting strain SG104, we constructed a series of metabolically engineered E. coli strains by deleting the key genes pfkA, pfkB and pgi, and replacing the original promoter of lacY. The co-expression systems for ManB, ManC, Gmd, WcaG, and FucT were optimized, and nine FucT enzymes were screened to improve the stoichiometric yields of 2'-FL. Furthermore, the gene gapA was regulated to further enhance 2'-FL production, and the highest stoichiometric yield (0.498 mol 2'-FL/mol fructose) was achieved by using recombinant strain RFL38 (SG104ΔpfkAΔpfkBΔpgi119-lacYΔwcaF::119-gmd-wcaG-manC-manB, 119-AGGAGGAGG-gapA, harboring plasmid P30). In the scaled-up reaction, 41.6 g/L (85.2 mM) 2'-FL was produced by a fed-batch bioconversion, corresponding to a stoichiometric yield of 0.482 mol 2'-FL/mol fructose and 0.986 mol 2'-FL/mol lactose. CONCLUSIONS: The biosynthesis of 2'-FL using recombinant E. coli from fructose was optimized by metabolic engineering strategies. This is the first time to realize the biological production of 2'-FL production from fructose with high stoichiometric yields. This study also provides an important reference to obtain a suitable distribution of carbon flux between 2'-FL synthesis and glycolysis.
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Escherichia coli , Fructosa , Humanos , Escherichia coli/metabolismo , Fructosa/metabolismo , Trisacáridos , Oligosacáridos , Ingeniería Metabólica , Fucosiltransferasas/genéticaRESUMEN
A donor-acceptor Schiff-base fluorescent probe BKS with chelation enhanced fluorescence (CHEF) mechanism was designed and synthesized via benzophenone(Acceptor), salicylaldehyde and carbazole(Donor) for Al3+ detection, which exhibited typical aggregation-induced emission (AIE) characteristic. BKS probe could provide outstanding selectivity to Al3+ with a prominent fluorescence "turn-on" at 545 nm in a wide pH range from 2 to 11. By the Job's plot, the binding stoichiometry ratio of probe BKS to Al3+ was determined 1:1. The proposed strategy offered a very low limit of detection at 1.486 µM in THF/H2O(V/V = 1:4, HEPBS = 10 mM, pH = 7.40), which was significantly lower than the standard of WHO (Huang et al., Microchem J 151:104195, 2019)-(Yongjie Ding et al., Spectrochim Acta Mol Biomol Spectrosc 167:59-65, 2021) guidelines for drinking water. BKS probe could provide a wider linear detection range of 50 to 500 µM. Furthermore, the probe could hardly be interfered by other examined metal ions. The analysis of Al3+ in real water samples with appropriate recovery (100.72 to 102.85) with a relative standard deviation less than 2.82% indicated the accuracy and precision of BKS probe and the great potential in the environmental monitoring of Al3+.
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PURPOSE: To evaluate the utility of galactomannan testing of intraocular fluid in the diagnosis of Aspergillus endophthalmitis (AE). METHODS: This retrospective study enrolled three groups of patients, including those with 17 eyes with AE; 20 eyes with intraocular infection of bacteria, viruses, or other fungi; and 19 eyes with cataract. Intraocular fluid from all these patients was collected for galactomannan testing. In addition, the receiver operating characteristic curves and diagnostic significance were analyzed. RESULTS: The mean optical density index (ODI) of galactomannan was 5.77 ± 1.73 in the AE group, which was significantly higher than that in the non- Aspergillus intraocular infection group (0.19 ± 0.11, P < 0.001) and the negative control group (0.29 ± 0.27, P < 0.001). The area under the receiver operating characteristic curve (area under the curve) was 1.00 (95% confidence interval, 1.00-1.00; P < 0.001) in the AE group and the other two groups. At a cutoff optical density index of 1.88, the sensitivity and specificity were 100.0% and 100.0%, respectively, and the Youden index reached its highest value of 1.00. CONCLUSION: Galactomannan testing of intraocular fluid indicated good sensitivity and specificity for the diagnosis of AE, thereby promising a rapid diagnostic modality for AE.
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Aspergilosis , Endoftalmitis , Infecciones Fúngicas del Ojo , Galactosa , Mananos , Curva ROC , Humanos , Mananos/análisis , Endoftalmitis/diagnóstico , Endoftalmitis/microbiología , Galactosa/análogos & derivados , Estudios Retrospectivos , Masculino , Femenino , Infecciones Fúngicas del Ojo/diagnóstico , Infecciones Fúngicas del Ojo/microbiología , Persona de Mediana Edad , Anciano , Aspergilosis/diagnóstico , Aspergilosis/microbiología , Aspergilosis/metabolismo , Adulto , Aspergillus/aislamiento & purificación , Humor Acuoso/metabolismo , Humor Acuoso/microbiología , Anciano de 80 o más Años , Sensibilidad y Especificidad , Cuerpo Vítreo/microbiología , Cuerpo Vítreo/metabolismo , Biomarcadores/metabolismoRESUMEN
PURPOSE: To explore the clinical value of ß-D-glucan (BDG) testing and metagenomic next-generation sequencing (mNGS) for detecting the pathogens of fungal endophthalmitis (FE). METHODS: This study included 32 cases (32 eyes) with FE and 20 cases (20 eyes) with intraocular inflammation caused by other etiologies. All patients underwent extraction of aqueous humor or vitreous fluid samples for BDG testing and mNGS. The diagnostic performance and total clinical concordance rate of BDG testing and mNGS for FE were evaluated and calculated based on the results of the clinical diagnosis. RESULTS: Among the clinically diagnosed FE, the positivity rates of BDG testing and mNGS (90.63%) were both significantly higher ( P < 0.001) than that of microbial cultures (53.13%). There was 100% consistency in pathogen identification using mNGS and culture identification for culture-positive cases. The area under the curve was 0.927 for BDG testing and 0.853 for mNGS. When the two tests were combined, sensitivity (93.75%), specificity (100.00%), and total clinical concordance rate (96.15%) were all improved, compared with the single tests. CONCLUSION: The positive rates of BDG test and mNGS were markedly higher than those of cultures in FE identification. The combination of these two tests showed improved performance when compared with individual tests.
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Humor Acuoso , Endoftalmitis , Infecciones Fúngicas del Ojo , Secuenciación de Nucleótidos de Alto Rendimiento , Metagenómica , Cuerpo Vítreo , beta-Glucanos , Humanos , Infecciones Fúngicas del Ojo/diagnóstico , Infecciones Fúngicas del Ojo/microbiología , Endoftalmitis/diagnóstico , Endoftalmitis/microbiología , Masculino , Persona de Mediana Edad , Femenino , Humor Acuoso/microbiología , beta-Glucanos/análisis , Cuerpo Vítreo/microbiología , Anciano , Metagenómica/métodos , Adulto , Estudios Retrospectivos , Hongos/aislamiento & purificación , Hongos/genética , ADN de Hongos/análisis , Proteoglicanos , Anciano de 80 o más AñosRESUMEN
BACKGROUND: This study assessed the impact of pressure-controlled ventilation (PCV) focusing on end-inspiratory flow rate on the incidence of postoperative pulmonary complications (PPCs) and inflammation levels in patients undergoing spinal surgery in the prone position. METHODS: A total of 187 patients who underwent posterior spinal surgery were enrolled and randomly divided into 3 groups: 61 in the volume-controlled ventilation (VCV) group (group V), 62 in the PCV-volume-guaranteed (VG) group (group P1), and 64 in the PCV-VG end-expiratory zero flow rate group (group P2). Indicators including tidal volume (VT), peak airway pressure (Ppeak), and dynamic lung compliance (Cdyn) were recorded. The Ppeak, Cdyn, PETCO2, and oxygenation index (PaO2/FiO2) after intubation (T0), after prone position (T1), 60 min after prone position (T2), and after supine position at the end of surgery (T3) of the three groups were collected. RESULTS: In the within-group comparison, compared with T0, Ppeak increased at T1 - 2 in groups V and P1 (P < 0.01), whereas it decreased at T1 - 3 in group P2 (P < 0.01). Cdyn decreased at T1 - 2 and PaO2/FiO2 increased at T1 - 3 in all three groups (P < 0.01), and PaO2/FiO2 increased at T1 - 3 (P < 0.01). Compared with group V, Ppeak decreased at T0 - 3 in group P1 (P < 0.01) and at T1 - 3 in group P2 (P < 0.01), while Cdyn increased at T0 - 3 in groups P1 and P2 (P < 0.01). Compared with group P1, Ppeak was elevated at T0 (P < 0.01) and decreased at T1 - 3 (P < 0.05), and Cdyn was elevated at T0 - 3 in group P2 (P < 0.01). The total incidence of PPCs in group P2 was lower than that in group V (P < 0.01). Compared with the preoperative period, serum interleukin 6 (IL-6) and C-reactive protein (CRP) levels were increased at 24 and 72 h after surgery in group V (P < 0.01), whereas that was increased at 24 h after surgery in group P1 and group P2 (P < 0.01). Compared with group V, serum IL-6 and CRP levels were reduced at 24 h after surgery in groups P1 and P2 (P < 0.01 or < 0.05). CONCLUSION: In patients undergoing spinal surgery in the prone position, PCV-VG targeting an end-inspiratory zero flow rate lowers the incidence of PPCs and inflammation levels.
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Interleucina-6 , Síndrome de Dificultad Respiratoria , Humanos , Posición Prona , Respiración Artificial , Volumen de Ventilación PulmonarRESUMEN
BACKGROUND: The microbial community plays a crucial role in Chinese strong-flavor baijiu (SFB) fermentation. However, the seasonal dynamics of the microbial community in the SFB fermentation system and its contribution to the unique flavor of SFB have not been fully elucidated. In this study, we investigated the seasonal dynamics of the microbial community through 16S rRNA and ITS gene sequencing. RESULTS: The results revealed significant temporal dynamics of microbial communities and environmental variables throughout the four seasons. The influence of seasons on fungal communities was found to be more significant than on bacterial communities. The diversity of bacteria was higher during the winter and summer, whereas fungal diversity was more prominent in summer and autumn. Stochastic processes maintained their dominance in microbial assembly throughout all four seasons but the significance of heterogeneous selection increased during summer for both bacteria and fungi, whereas homogeneous selection became more pronounced during winter for fungi. The pH and environmental temperature were important drivers of microbial community assembly across different seasons, primarily impacting the core genera responsible for the production of major volatile flavor compounds (VFCs), especially ethyl caproate. CONCLUSION: These findings provide new insights into the impact of seasons on microbial communities and hold promise for improving the quality-control measures for SFB brewed in different seasons. © 2024 Society of Chemical Industry.
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Bacterias , Fermentación , Aromatizantes , Hongos , Microbiota , Estaciones del Año , Bacterias/genética , Bacterias/clasificación , Bacterias/metabolismo , Bacterias/aislamiento & purificación , Hongos/genética , Hongos/clasificación , Hongos/metabolismo , Hongos/aislamiento & purificación , Aromatizantes/metabolismo , Aromatizantes/química , Compuestos Orgánicos Volátiles/metabolismo , Compuestos Orgánicos Volátiles/análisis , Gusto , China , ARN Ribosómico 16S/genética , Vino/análisis , Vino/microbiologíaRESUMEN
BACKGROUND: Cat-scratch disease (CSD) is caused by Bartonella henselae infection. In atypical cases of CSD, pathogen determination is challenging. We report a case of Bartonella neuroretinitis with neither a clear history of scratches nor typical general symptoms. The diagnosis was made using metagenomic next-generation sequencing (mNGS), a high-throughput sequencing technology. CASE PRESENTATION: A female patient presented to the ophthalmologist with complaint of blurred vision in her right eye. Although with history of raising a cat, she reported no clear history of scratches or typical general symptoms, except a fever of unknown origin which resolved spontaneously. The best corrected visual acuity (BCVA) of the right eye was count fingers. Fundus examination showed optic disc oedema, macular exudates and inferior exudative retinal detachment. Laboratory examination results showed increased value of serum C-reactive protein and erythrocyte sedimentation rate. Ocular involvement of toxoplasmosis, syphilis and tuberculosis were excluded. To identify the possible causative pathogen of the disease, mNGS of aqueous humour sample was performed and 521 reads of B. henselae were identified. Serological test results further showed a positive immunoglobulin G (IgG) titre of 1:64. Taking the contact history, clinical manifestations, mNGS and serological results into consideration, the diagnosis of Bartonella neuroretinitis (ocular CSD) was made. After appropriate treatment, the BCVA of the right eye improved to 20/25 in the last follow-up. Fundus examination showed a normal optic disc and macula, and the exudates had reduced. CONCLUSION: mNGS, a fast and unbiased method, can be used to detect B. henselae (if present) in intraocular fluid samples.; however, the results should be interpreted together with the clinical symptoms and other auxiliary test results.
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Key Clinical Message: Traditional treatment options are often insufficient in treating severe dry eyes caused by systemic diseases. This case demonstrates that ocular immersion hydrotherapy significantly alleviated symptoms and ocular surface inflammation in ocular graft-versus-host disease. Based on these findings, we propose it as a promising option for managing severe dry eye disease. Abstract: This case report investigates the efficacy of ocular immersion hydrotherapy (OIH) in treating severe dry eye secondary to ocular graft-versus-host disease (oGVHD). A 35-year-old female with a history of acute myeloid leukemia-M2 and subsequent hematopoietic stem cell transplantation (HSCT) developed high-intensity oGVHD unresponsive to conventional treatments, including topical corticosteroids and lubricants. We introduced OIH, utilizing sterilized swimming goggles filled with intraocular irrigating solutions, providing a moist microenvironment for the ocular surface. Symptoms were significantly relieved after treatment. Corneal filaments and epithelial defects were significantly reduced, and in vivo confocal microscopy (IVCM) demonstrated resolution of inflammation and reappearance of corneal nerves. This case indicates that OIH could be a promising therapeutic approach for severe dry eye conditions arising from oGVHD, particularly for patients refractory to traditional treatments. Further studies are warranted to elucidate the long-term benefits and mechanisms of OIH in oGVHD management.
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In this study, the graded hierarchical hexagonal honeycomb (GHHH) integrating gradient design and hierarchical design was fabricated using the 3D-printing technique, and its in-plane elastic properties were investigated theoretically, experimentally, and numerically. Theoretical solutions were developed based on the Euler beam theory to predict the effective elastic modulus and Poisson's ratio of GHHH, and theoretical values were in good agreement with the experimental and numerical results. The effect of gradient design and hierarchical design on the in-plane elastic properties of GHHH was also analyzed and compared. Results showed that the hierarchical design has a more significant effect on Poisson's ratio and adjusting the internal forces of GHHH compared with the gradient design. In addition, it was found that GHHH exhibited higher stiffness compared with regular hexagonal honeycomb (RHH), graded hexagonal honeycomb (GHH), and vertex-based hierarchical hexagonal honeycomb (VHHH) under the constraint of the same relative density, respectively. Specifically, the effective elastic modulus of GHHH can be enhanced by 119.82% compared to that of RHH. This research will help to reveal the effect of integrating hierarchical design and gradient design on the in-plane elastic properties of honeycombs.
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The production of caproic acid (CA) and hydrogen gas (H2) from organic wastewater is economically attractive. The Ruminococcaceae bacterium CPB6 has demonstrated potential for CA production from lactate-containing wastewater. However, our understanding of the effects of Fe2+ and Mg2+ on the growth and metabolism of strain CPB6 remains limited. Therefore, this study aims to investigate the impact of Fe2+ and Mg2+ on CA and H2 production, as well as on the expression of key genes involved in CA and H2 biosynthesis pathway. The results indicate that Fe2+ positively affects cell proliferation and H2 production while minimally impacting CA production. The highest levels of H2 production were achieved with the addition of 200 mg/L Fe2+. Conversely, Mg2+ significantly enhances CA and H2 production, with the optimal yield observed in a medium enriched with 300 mg/L Mg2+. Reverse transcription quantitative PCR (RT-qPCR) analysis reveals that Fe2+ promotes the expression of the hydrogenase gene, whereas Mg2+ has a negligible effect on hydrogenase expression. Notably, Fe2+ and Mg2+ inhibit the expression of key genes involved in CA synthesis. These findings suggest that Fe2+ enhances H2 production by boosting cell biomass and the expression of the hydrogenase gene, whereas Mg2+ improves CA and H2 production primarily by increasing cell biomass rather than influencing the expression of functional genes involved in CA biosynthesis.
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Propionic acid as an important C3 platform chemical has been widely used in food, pharmaceutical, and chemical fields. The chemical synthesis of propionic acid from petroleum and other chemical products has serious environmental pollution and is not sustainable. In recent years, the production of propionic acid by microbial transformation of renewable resources has received extensive attention. Focusing on the biomanufacturing of propionic acid, this paper firstly reviews the studies about the metabolic engineering of Propionibacterium and the pathway reconstruction in heterogeneous hosts such as Escherichia coli and Saccharomyces cerevisiae. Secondly, this paper reviews the recent progress in the synthesis of high-purity propionic acid from L-threonine or bio-based 1, 2-propanediol by the design and modification of the pathway of Pseudomonas putida KT2440 based on synthetic biology.
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Escherichia coli , Ingeniería Metabólica , Propionatos , Propionibacterium , Pseudomonas putida , Saccharomyces cerevisiae , Propionatos/metabolismo , Saccharomyces cerevisiae/metabolismo , Propionibacterium/metabolismo , Escherichia coli/metabolismo , Pseudomonas putida/metabolismo , Biología SintéticaRESUMEN
Compatible solutes are highly water-soluble organic osmolytes produced by microorganisms to adapt to extreme environments, such as high salinity and osmotic pressure. Among these, ectoine plays a crucial role in repairing and protecting nucleic acids, protein, biofilms, and cells. As a result, it has found widespread applications in cosmetics, biological agents, the enzyme industry, medicine, and other fields. Currently, the market value of ectoine is around US$ 1 000/kg, with a global demand reaching 15 000 tons per year. Although halophilic bacteria serve as the natural source of ectoine synthesis, its production in high-salinity media presents challenges such as equipment corrosion and high cost for industrial production. Advancements in functional genomics, systems biology, and synthetic biology have paved the way for the development of high-yielding cell factories through metabolic engineering, leading to significant progress. For example, engineered Escherichia coli achieved a maximum ectoine titer of 131.8 g/L, with a productivity of 1.37 g/(L·h). This review aims to explore the biosynthetic pathway, biochemical characteristics of key enzymes, and the biosynthesis of ectoine, shedding light on current research status and offering insights for industrial-scale ectoine production.
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Aminoácidos Diaminos , Ingeniería Metabólica , Aminoácidos Diaminos/biosíntesis , Aminoácidos Diaminos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Vías Biosintéticas , HidroliasasRESUMEN
Cytidine-5'-diphosphate choline (CDP-choline) plays a crucial role in the formation of the phospholipid bilamolecular layer in cell membranes and the stabilization of the neurotransmitter system, acting as a precursor to phosphatidylcholine and acetylcholine. CDP-choline has been found effective in treating functional and consciousness disorders resulting from brain injury, Parkinson's disease, depression and glaucoma, and other conditions. As such, CDP-choline is widely utilized in clinical medicine and health care products. The conventional chemical synthesis process of CDP-choline is gradually being replaced by biosynthesis due to the expensive and toxic reagents involved, the production of various by-products, and the high cost of industrial production. Biosynthesis of CDP-choline offers two strategies: microbial fermentation and biocatalysis. Microbial fermentation utilizes inexpensive raw materials but results in a relatively low conversion rate and requires a complex separation and purification process. Biocatalysis, on the other hand, involves two stages: the growth of a living "catalyst" and the conversion of the substrate. Although the synthetic process in biocatalysis is more complex, it offers a higher conversion ratio, and the downstream processing technique for extraction is relatively less costly. Consequently, biocatalysis is currently the primary strategy for the industrial production of CDP-choline. This review aims to summarize the progress made in both chemical synthesis and biosynthesis of CDP-choline, with particular focus on the metabolic pathway and the synthetic processes involved in biocatalysis, in order to provide insights for the industrial production of CDP-choline.
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Citidina Difosfato Colina , Citidina Difosfato Colina/biosíntesis , Citidina Difosfato Colina/metabolismo , Biocatálisis , Fermentación , HumanosRESUMEN
Superhydrophobic surfaces applying on concrete can greatly improve the durability of concrete by preventing the damage from water. However, traditional design of superhydrophobic concrete surfaces by external coating encounters to problems of flaking and poor surface robustness, while that by adding hydrophobic agents or particles faces the challenges of strength damage of concrete. Drawing inspiration from the carbonation phenomenon of concrete, here a new design of in situ growing superhydrophobic structures on concrete is proposed: The concrete sample is impregnated into Mg2+-containing silane-water system with continuous CO2 injection. The contact angle of the concrete surface achieves 171.9° without obvious strength decrease after 120 min, which are mainly attributed to the formation of CaxMg1-xCO3 crystals with micro-nano-structures and the reduction of carbonates surface energy by silane. This superhydrophobic concrete structure can be divided into a superhydrophobic-hydrophobic-hydrophilic three layers structure, providing the stable water-proof protection under mechanical fatigue, capillary water absorption, UV aging, sulfate attack, and impurity water impact tests due to the in situ growing robust superhydrophobic structures. Furthermore, it captures 29.80 g m-2 CO2 during the reaction process, providing new insights for the design and preparation of eco-friendly superhydrophobic concrete.
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The main chemical compositions of 201 surface sediments and 53 deep sediment samples from Chaohu Lake, China, were analysed. Since the surface sediments (0-2 cm depth) in Chaohu Lake are modern sediments, this paper mainly focuses on the deep sediments (50-100 cm depth) in Chaohu Lake. Particle size analysis and magnetization determination of the CH3 and CH4 column sediment samples were carried out. The age determination data of the CH-1 column sediment samples are reported. A systematic study of the rocks and their chemical compositional characteristics in the Chaohu Lake Basin was also carried out. The results of this study show that four positive chemical weathering indicators and one negative chemical weathering indicator are applicable to the study of Chaohu Lake. The mean CIA of the Chaohu Lake sediments was less than 65, indicating that the Chaohu Lake Basin experienced weak chemical weathering and that the palaeoclimate was cold and dry. Vertical variations in the mean grain size and magnetization in the CH3 and CH4 columnar sediments reflect changes in the depositional environment and climate during deposition of the Chaohu Lake sediments. The age data from the CH-1 column sediment samples directly indicate deposition of the deep sediments in Chaohu Lake during the Little Ice Age in eastern China (AD 1380-1880). The Th/U, Sc/Th, Rb/Sr, Na2O/K2O, CaO/MgO and OC/N ratios of the Chaohu sediments reflect palaeoclimate characteristics and the chemical compositions of the source rocks in the Chaohu Lake basin. The correlations of the CIA, CIW, PIA, and CIX with the chemical compositional ratios provide information on the palaeoclimate and the distribution of the chemical compositions. The CIA, CIW, PIA, and CIX were not correlated with Cd, Pb, As, Hg, or P. In contrast, the CIA, CIW, PIA, and CIX were significantly positively correlated with Cr and N. The WIP was inconsistently correlated with the selected chemical components. Therefore, the study of the correlations of chemical weathering indicators with four heavy metals and two eutrophication-related elements is of little significance. The study of the chemical weathering characteristics of deep sediments of inland lakes should be combined with assessment of the geological characteristics of the lake basins, particularly the analysis of the chemical composition of the rocks in the lake basins.
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Tricarboxylic acid cycle (TCA cycle) plays an important role for aerobic growth of heterotrophic bacteria. Theoretically, eliminating TCA cycle would decrease carbon dissipation and facilitate chemicals biosynthesis. Here, we construct an E. coli strain without a functional TCA cycle that can serve as a versatile chassis for chemicals biosynthesis. We first use adaptive laboratory evolution to recover aerobic growth in minimal medium of TCA cycle-deficient E. coli. Inactivation of succinate dehydrogenase is a key event in the evolutionary trajectory. Supply of succinyl-CoA is identified as the growth limiting factor. By replacing endogenous succinyl-CoA dependent enzymes, we obtain an optimized TCA cycle-deficient E. coli strain. As a proof of concept, the strain is engineered for high-yield production of four separate products. This work enhances our understanding of the role of the TCA cycle in E. coli metabolism and demonstrates the advantages of using TCA cycle-deficient E. coli strain for biotechnological applications.
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Ciclo del Ácido Cítrico , Escherichia coli , Ciclo del Ácido Cítrico/genética , Escherichia coli/metabolismo , Fermentación , Biotecnología , BacteriasRESUMEN
There are no Food and Drug Administration-approved drugs for treating noise-induced hearing loss (NIHL), reflecting the absence of clear specific therapeutic targets and effective delivery strategies. Noise trauma is demonstrated results in nicotinamide adenine dinucleotide (NAD+) downregulation and mitochondrial dysfunction in cochlear hair cells (HCs) and spiral ganglion neurons (SGNs) in mice, and NAD+ boosted by nicotinamide (NAM) supplementation maintains cochlear mitochondrial homeostasis and prevents neuroexcitatory toxic injury in vitro and ex vivo, also significantly ameliorated NIHL in vivo. To tackle the limited drug delivery efficiency due to sophisticated anatomical barriers and unique clearance pathway in ear, personalized NAM-encapsulated porous gelatin methacryloyl (PGMA@NAM) are developed based on anatomy topography of murine temporal bone by micro-computed tomography and reconstruction of round window (RW) niche, realizing hydrogel in situ implantation completely, NAM sustained-release and long-term auditory preservation in mice. This study strongly supports personalized PGMA@NAM as NIHL protection drug with effective inner ear delivery, providing new inspiration for drug-based treatment of NIHL.
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Gelatina , Pérdida Auditiva Provocada por Ruido , Metacrilatos , Ratones , Animales , Pérdida Auditiva Provocada por Ruido/tratamiento farmacológico , Pérdida Auditiva Provocada por Ruido/prevención & control , Niacinamida/uso terapéutico , NAD , Preparaciones de Acción Retardada/uso terapéutico , Porosidad , Microtomografía por Rayos XRESUMEN
BACKGROUND: Postoperative pulmonary complications (PPCs) after one-lung ventilation (OLV) significantly impact patient prognosis and quality of life. OBJECTIVE: To study the impact of an optimal inspiratory flow rate on PPCs in thoracic surgery patients. METHODS: One hundred eight elective thoracic surgery patients were randomly assigned to 2 groups in this consort study (control group: n = 53 with a fixed inspiratory expiratory ratio of 1:2; and experimental group [flow rate optimization group]: n = 55). Measurements of Ppeak, Pplat, PETCO2, lung dynamic compliance (Cdyn), respiratory rate, and oxygen concentration were obtained at the following specific time points: immediately after intubation (T0); immediately after starting OLV (T1); 30 min after OLV (T2); and 10 min after 2-lung ventilation (T4). The PaO2:FiO2 ratio was measured using blood gas analysis 30 min after initiating one-lung breathing (T2) and immediately when OLV ended (T3). The lung ultrasound score (LUS) was assessed following anesthesia and resuscitation (T5). The occurrence of atelectasis was documented immediately after the surgery. PPCs occurrences were noted 3 days after surgery. RESULTS: The treatment group had a significantly lower total prevalence of PPCs compared to the control group (3.64% vs. 16.98%; P = 0.022). There were no notable variations in peak airway pressure, airway plateau pressure, dynamic lung compliance, PETCO2, respiratory rate, and oxygen concentration between the two groups during intubation (T0). Dynamic lung compliance and the oxygenation index were significantly increased at T1, T2, and T4 (P < 0.05), whereas the CRP level and number of inflammatory cells decreased dramatically (P < 0.05). CONCLUSION: Optimizing inspiratory flow rate and utilizing pressure control ventilation -volume guaranteed (PCV-VG) mode can decrease PPCs and enhance lung dynamic compliance in OLV patients.
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Ventilación Unipulmonar , Complicaciones Posoperatorias , Humanos , Masculino , Femenino , Persona de Mediana Edad , Complicaciones Posoperatorias/prevención & control , Ventilación Unipulmonar/métodos , Anciano , Procedimientos Quirúrgicos Torácicos/efectos adversos , Procedimientos Quirúrgicos Torácicos/métodos , Enfermedades Pulmonares/prevención & control , Enfermedades Pulmonares/etiología , Enfermedades Pulmonares/fisiopatología , Pulmón/fisiopatología , Estudios ProspectivosRESUMEN
Background: This study presents real-world evidence on the clinical outcomes of the Alberta Complementary Health Integration Project (ABCHIP), which utilized acupuncture to address pain and mental health issues in two vulnerable populations in Alberta: youth (aged 24 and below) and elderly (aged 55 and above). Methods: Over 282 days, a total of 606 patients received 5,424 acupuncture treatments. Tailored to each patients' specific pain and mental health concerns, an individualized treatment plan was selected, following a standard treatment protocol lasting 1 to 3 months. Patients were evaluated at least twice: initially and upon completing therapy. Primary treatment outcomes were assessed using various measures, including the Brief Pain Inventory (BPI), Pittsburgh Sleep Quality Index (PSQI), Patient Health Questionnaire 9 (PHQ9), PROMIS Anxiety 8a and its pediatric form PROMIS Anxiety-Pediatric, PROMIS Short Form v1.0 Fatigue 8a and its pediatric counterpart PROMIS Pediatric Short Form v2.0 Fatigue 10a, PROMIS Short Form v1.1 Anger 5a and its version PROMIS SF v2.0 5a, and EQ-5D-5L. These measures gauged pain reduction, improved sleep quality, reduced depression, anxiety, fatigue, anger, and quality of life, respectively. Results: Analysis of data from 500 patients who received at least 6 acupuncture sessions through ABCHIP showed statistically significant improvements in clinical outcomes. Among this group, the subgroup of 235 patients who received at least 12 sessions demonstrated the most favorable treatment outcomes, including an 75.5% reduction in pain severity, a 53.1% improvement in sleep quality, a 78.4% drop in depression, a 41.1% decline in anxiety, a 43.7% decrease in fatigue, a 38.2% decrease in anger, and a 42.6% improvement in overall quality of life. Conclusion: Integrating acupuncture with usual care demonstrates promise in enhancing mental health, alleviating chronic and general pain, and improving overall quality of life. The findings suggest that integrative programs, such as ABCHIP, present an effective approach to addressing pain and mental health concerns in vulnerable populations, providing valuable insights for future healthcare interventions.