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1.
Neuroreport ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38973492

RESUMEN

Sepsis-associated encephalopathy (SAE) is a severe complication of sepsis, however, its exact mechanism remains unknown. This study aimed to evaluate whether clusterin is essential to the development of SAE during the aging process of astrocytes. In the study, septic mice were established with cecal ligation and puncture (CLP) and lipopolysaccharides were applied to astrocytes in vitro. Evan's blue dye was used in vivo to show blood-brain barrier (BBB) permeability. A morris water maze test was conducted to assess cognitive functions of the mice. Clusterin-knockout mice were used to examine the effect of clusterin on sepsis. The astrocytes were transfected with lentivirus expressing clusterin cDNA for clusterin overexpression or pYr-LV-clusterin small hairpin RNA for clusterin knockdown in vitro. The expression of clusterin, p-p53, p21, GDNF, and iNOS was detected. he CLP mice exhibited a higher clusterin expression in hippocampus tissue, aging astrocytes, lower GDNF expression and higher iNOS expression, accompanied with BBB damage and cognitive deficiency. Following clusterin knockout, this pathological process was further enhanced. In vitro, following lipopolysaccharides treatment, astrocytes exhibited increased clusterin, p-p53, p21, iNOS and decreased GDNF. Following clusterin knockdown, the cells exhibited a further increase in p-p53, p21, and iNOS and decrease in GDNF. Clusterin overexpression, however, helped inhibit astrocytes aging and neuroinflammation evidenced by decreased p-p53, p21, iNOS and increased GDNF. The present study has revealed that clusterin may exert its neuroprotective effect by preventing aging in astrocytes, suppressing the secretion of iNOS and promoting GNDF release.

2.
Clin Oral Investig ; 28(7): 368, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38862733

RESUMEN

OBJECTIVES: The aims of this clinical study were to investigate success rate, vital pulp survival rate, tooth survival rate and patient-reported masticatory ability by evaluating the pain symptoms and signs of the cracked teeth as well as Index of Eating Difficulty (IED) and Oral Health Impact Profile-14 (OHIP-14) questionnaire after cracked teeth were restored with occlusal veneers. MATERIALS AND METHODS: 27 cracked teeth of 24 patients with cold and/or biting pains without spontaneous/nocturnal pains were recruited in this study. The cracked teeth were restored with occlusal veneers fabricated by lithium disilicate ceramic. Cold test and biting test were used to evaluate pain signs. IED and OHIP-14 questionnaire were used to evaluate masticatory ability. FDI criteria was used to evaluate restorations. The paired Wilcoxon test was used to analyze significant differences of detection rate of pain signs, OHIP scores and IED grade before and after restorations. Kaplan-Meier survival curve was used to describe the success rate, vital pulp survival rate, and tooth survival rate. RESULTS: 27 cracked teeth were restored with occlusal veneers with average of 22.4-month follow-up. Two cracked teeth had pulpitis and pain signs of the other cracked teeth completely disappeared. OHIP total scores were significantly reduced after treatment. Scores of 'pain', 'occlusal discomfort', 'uncomfortable to eat', 'diet unsatisfactory' and 'interrupted meals' reduced significantly after treatment. After treatment, IED grades of 25 vital teeth were significantly lower than those before treatment. FDI scores of 25 restorations except for 2 teeth with pulpitis were no greater than 2. The 12 months accumulated pulp survival rate of the cracked teeth was 92.6%. The 12 months accumulated tooth survival rate was 100%. The success rate at the latest recall was 92.6%. CONCLUSION: Occlusal veneer restorations with success rate of 92.6% and the same pulp survival rate might be an effective restoration for treating the cracked teeth. CLINICAL RELEVANCE: The occlusal veneer restorations might be an option for treating the cracked teeth when cracks only involve enamel and dentin, not dental pulp.


Asunto(s)
Síndrome de Diente Fisurado , Coronas con Frente Estético , Humanos , Femenino , Masculino , Adulto , Estudios de Seguimiento , Síndrome de Diente Fisurado/terapia , Resultado del Tratamiento , Encuestas y Cuestionarios , Persona de Mediana Edad , Dimensión del Dolor , Porcelana Dental , Restauración Dental Permanente/métodos , Masticación/fisiología
3.
J Asian Nat Prod Res ; : 1-8, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38753589

RESUMEN

A pair of atropisomers secofumitremorgins C (1a) and D (1b), together with fifteen known alkaloids (2-16), were isolated from a saltern-derived fungus Aspergillus fumigatus GXIMD00544. The structures of atropisomers 1a and 1b were elucidated by the detailed spectroscopic data, chemical reaction and quantum chemical calculations. Compounds 1 and 8 displayed antifungal spore germination effects against plant pathogenic fungus associated with sugarcane Fusarium sp. with inhibitory rates of 53% and 77% at the concentration of 100 µM, repectively. Atropisomers 1 also exhibited antifouling potential against Balanus amphitrite larval settlement with an inhibitory rate of 96% at the concentration of 100 µM.

4.
PLoS One ; 19(5): e0304518, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38820377

RESUMEN

BACKGROUND: The arterial pressure of oxygen (PaO2)/inspiratory fraction of oxygen (FiO2) is associated with in-hospital mortality in patients with Coronavirus Disease 2019 (COVID-19) pneumonia. ΔPaO2/FiO2 [the difference between PaO2/FiO2 after 24 h of invasive mechanical ventilation (IMV) and PaO2/FiO2 before IMV] is associated with in-hospital mortality. However, the value of PaO2 can be influenced by the end-expiratory pressure (PEEP). To the best of our knowledge, the relationship between the ratio of (ΔPaO2/FiO2)/PEEP and in-hospital mortality remains unclear. This study aimed to evaluate their association. METHODS: The study was conducted in southern Peru from April 2020 to April 2021. A total of 200 patients with COVID-19 pneumonia requiring IMV were included in the present study. We analyzed the association between (ΔPaO2/FiO2)/PEEP and in-hospital mortality by Cox proportional hazards regression models. RESULTS: The median (ΔPaO2/FiO2)/PEEP was 11.78 mmHg/cmH2O [interquartile range (IQR) 8.79-16.08 mmHg/cmH2O], with a range of 1 to 44.36 mmHg/cmH2O. Patients were divided equally into two groups [low group (< 11.80 mmHg/cmH2O), and high group (≥ 11.80 mmHg/cmH2O)] according to the (ΔPaO2/FiO2)/PEEP ratio. In-hospital mortality was lower in the high (ΔPaO2/FiO2)/PEEP group than in the low (ΔPaO2/FiO2)/PEEP group [18 (13%) vs. 38 (38%)]; hazard ratio (HR), 0.33 [95% confidence intervals (CI), 0.17-0.61, P < 0.001], adjusted HR, 0.32 (95% CI, 0.11-0.94, P = 0.038). The finding that the high (ΔPaO2/FiO2)/PEEP group exhibited a lower risk of in-hospital mortality compared to the low (ΔPaO2/FiO2)/PEEP group was consistent with the results from the sensitivity analysis. After adjusting for confounding variables, we found that each unit increase in (ΔPaO2/FiO2)/PEEP was associated with a 12% reduction in the risk of in-hospital mortality (HR, 0.88, 95%CI, 0.80-0.97, P = 0.013). CONCLUSIONS: The (ΔPaO2/FiO2)/PEEP ratio was associated with in-hospital mortality in patients with COVID-19 pneumonia. (ΔPaO2/FiO2)/PEEP might be a marker of disease severity in COVID-19 patients.


Asunto(s)
COVID-19 , Mortalidad Hospitalaria , Respiración con Presión Positiva , Humanos , COVID-19/mortalidad , COVID-19/terapia , Femenino , Masculino , Persona de Mediana Edad , Anciano , Respiración con Presión Positiva/métodos , Oxígeno , SARS-CoV-2/aislamiento & purificación , Perú/epidemiología , Modelos de Riesgos Proporcionales
5.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 42(1): 111-120, 2024 Feb 01.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-38475959

RESUMEN

Noncarious lesions, a multifactorial condition encompassing tooth attrition, abrasion, and erosion, have a surge in prevalence and required increased attention in clinical practice. These nonbacterial-associated tooth defects can compromise aesthetics, phonetics, and masticatory functions. When providing full-arch fixed occlusal rehabilitation for such cases, the treatment strategy should extend beyond by restoring dentition morphology and aesthetics. This report details a complex case of erosive dental wear addressed through a fully digital, full-arch fixed occlusal rehabilitation. A 4D virtual patient was created using multiple digital data sources, including intraoral scanning, 3D facial scanning, digital facebow registration, and mandibular movement tracing. With a comprehensive understanding of the masticatory system, various types of microinvasive prostheses were customized for each tooth, including labial veneers, buccal-occlusal veneers, occlusal veneers, overlays, inlays, and full crowns, were customized for each tooth. The reported digital workflow offered a predictable diagnostic and treatment strategy, which was facilitated by virtual visualization and comprehensive quality control throughout the process.


Asunto(s)
Atrición Dental , Erosión de los Dientes , Humanos , Erosión de los Dientes/patología , Erosión de los Dientes/terapia , Tecnología Digital , Estética Dental , Incrustaciones
6.
Mar Drugs ; 22(2)2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38393034

RESUMEN

Six benzophenone derivatives, carneusones A-F (1-6), along with seven known compounds (7-13) were isolated from a strain of sponge-derived marine fungus Aspergillus carneus GXIMD00543. Their chemical structures were elucidated by detailed spectroscopic data and quantum chemical calculations. Compounds 5, 6, and 8 exhibited moderate anti-inflammatory activity on NO secretion using lipopolysaccharide (LPS)-induced RAW 264.7 cells with EC50 values of 34.6 ± 0.9, 20.2 ± 1.8, and 26.8 ± 1.7 µM, while 11 showed potent effect with an EC50 value of 2.9 ± 0.1 µM.


Asunto(s)
Antiinflamatorios , Aspergillus , Animales , Ratones , Estructura Molecular , Aspergillus/química , Antiinflamatorios/farmacología , Células RAW 264.7
7.
OMICS ; 27(5): 215-226, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37196148

RESUMEN

Glioblastoma multiforme (GBM) is a highly malignant brain tumor where new biomarkers and drug targets are much needed in the oncology clinic. miR-433 was identified as a tumor-suppressing miRNA in several different types of human cancer. However, the integrative biology of miR-433 in GBM is still largely unknown. By analyzing the expression profiles of miR-433 in 198 patients with glioma at The Cancer Genome Atlas, we found that the miR-433 expression was decreased in glioma whereas the low expression of miR-433 was significantly associated with shorter overall survival. We then conducted in vitro studies and demonstrated that increased expression of miR-433 suppressed the proliferation, migration, and invasion of LN229 and T98G cells, two representative glioma cell lines. Further, using in vivo mouse model, we found that upregulation of miR-433 inhibited the tumor growth of glioma cells. To situate the integrative biology understanding of the action of miR-433 in glioma, we identified ERBB4 as a gene targeted directly by miR-433 in LN229 and T98G cells. Overexpressed ERBB4 rescued the phenotype caused by overexpression of miR-433. Finally, we showed that miR-433 suppressed the PI3K/Akt pathway in glioma cells. In conclusion, our study demonstrated that miR-433 could potentially act as a tumor suppressor for GBM and may serve as a potential therapeutic target for GBM. Further integrative biology and clinical translational research are warranted to evaluate miR-433 in GBM.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Glioma , MicroARNs , Humanos , Animales , Ratones , Glioblastoma/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Línea Celular Tumoral , Transducción de Señal/genética , MicroARNs/genética , MicroARNs/metabolismo , Glioma/genética , Neoplasias Encefálicas/metabolismo , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica/genética , Movimiento Celular/genética , Receptor ErbB-4/genética , Receptor ErbB-4/metabolismo
8.
PhytoKeys ; 220: 1-16, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37251610

RESUMEN

Over the course of the recent decade, the composition of Alsineae has been drastically changed by means of molecular phylogeny. However, the genus Brachystemma has not been sampled in any of the previous studies, and its phylogenetic position is still pending. In addition, the related species Stellariaovatifolia, which has at times been placed in Brachystemma, Schizotechium, or Stellaria, has also not been sampled. Here, nuclear ribosomal internal transcribed spacer (ITS) and four plastid regions (trnL-F, matK, rbcL, rps16) were used to conduct phylogenetic analyses within Caryophyllaceae and the tribe Alsineae. Ancestral characters (petal margin and number of seeds) were reconstructed in the tribe Alsineae based on the phylogenetic results. Our results indicate that Brachystemma is nested in the tribe Alsineae and forms a monophylum with S.ovatifolia, and apically lobed petals and numerous seeds may be the ancestral characters in the tribe Alsineae. Based on our study, Stellariaovatifolia should be considered within Brachystemma, and Brachystemma is clearly a separate genus and now includes two species.

9.
ACS Appl Mater Interfaces ; 15(17): 20958-20965, 2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37079481

RESUMEN

Low cost is the eternal theme for any commercial production. Numerous efforts have been explored to realize low-cost, high-efficiency perovskite solar cells (PSCs), such as replacing the traditional spin-coating method with an economical printing strategy, simplifying the device structure, reducing the number of functional layers, etc. However, there are few reports on the use of low-cost precursors. Herein, we enable the low-cost fabrication of efficient PSCs based on a very cheaper low-purity PbI2 via powder engineering. The low-purity PbI2 is blended with formamidinium iodide followed by dissolving in a 2-methoxyethanol solvent, and then, the high-quality FAPbI3 powders are formed via an inverse temperature crystallization process and solvent washing after several simple processes to reduce the impurities. As a result, the devices fabricated using the as-synthesized black powders based on the low-purity PbI2 exhibit a champion power conversion efficiency (PCE) of 23.9% and retained ∼95% of the initial PCE after ∼400 h of storage in the conditions of 25 ± 5 °C and 25 ± 5 RH% without encapsulation. In addition, the upscaling fabrication of a 5 cm × 5 cm solar minimodule also demonstrates an impressive efficiency of 19.5%. Our findings demonstrate an economic strategy for the commercialization of PSCs from the perspective of low-cost production.

10.
Plant Divers ; 45(1): 6-19, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36876305

RESUMEN

Fruit colour is essential to seed dispersal, speciation, and biological diversity in global ecosystems. The relationship between fruit-colour variation and species diversification has long been of interest in evolutionary biology, but remains poorly understood at the genus level. Here, we used Callicarpa, a typical representative of pantropical angiosperm, to analyse whether fruit colours are correlated with biogeographic distribution, dispersal events, and diversification rate. We estimated a time-calibrated phylogeny for Callicarpa and reconstructed ancestral fruit colour. Utilizing phylogenetic methods, we estimated the major dispersal events across the phylogenetic tree and the most likely fruit colours related to each dispersal event, and tested whether the dispersal frequencies and distances of the four fruit colours between major biogeographical areas were equal. We then tested whether fruit colours are correlated with latitude, elevation, and diversification rate. Biogeographical reconstructions showed that Callicarpa originated in the East Asia and Southeast Asia during the Eocene (∼35.53 Ma) and diverse species diverged mainly in the Miocene and lasted into the Pleistocene. Large-scale dispersal events were significantly associated with violet-fruited lineages. Furthermore, different fruit colours were markedly correlated with different latitudes and elevations (e.g., violet fruits were correlated with higher latitudes and elevations; red fruits and black fruits with lower latitudes; white fruits with higher elevations). Notably, violet fruits were statistically associated with highest diversification rates, driving fruit colour variation among different regions globally. Our results contribute to further understanding why fruit colour is so variable at the genus level of angiosperms in different areas around the world.

11.
J Nat Med ; 77(3): 496-507, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37002508

RESUMEN

Five new phenylethanoid glycosides integerrima A-E (1-5) were isolated from the stem of Callicarpa integerrima for the first time. Their structures were elucidated by extensive spectroscopic analyses. In addition, cytotoxicity, anti-adipogenic and antioxidant activities were evaluated. All the phenylethanoid glycosides would be nontoxic to the normal human hepatocytes LO-2 and pre-adipocytes 3T3-L1 cell lines, significantly promote the proliferation of normal hepatocytes, thus displaying the potential for hepatoprotective. Integerrima A (1), C (3) and D (4) exhibited selectively moderate cytotoxic activity against the hepatoma cell lines Bel-7402, with the IC50 value at 72.66, 80.43 and 84.88 µmol/L, respectively. Moreover, integerrima D (4) had significant activities on reducing lipid droplet formation, with the inhibition rate of 48.02% on the concentration of 200 µg/mL. Finally, the result of FRAP assays exhibited remarkable antioxidant activity in integerrima E (5), which was close to the positive control ascorbic acid with the concentration of 100 µg/mL.


Asunto(s)
Antineoplásicos , Callicarpa , Humanos , Glicósidos/farmacología , Glicósidos/química , Callicarpa/química , Estructura Molecular
12.
Ecol Evol ; 13(3): e9913, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36969937

RESUMEN

Callicarpa stoloniformis sp. nov. (Lamiaceae) is described as a new species from Fujian Province of China on the basis of both morphological and molecular data. The new species is morphologically most close to C. hainanensis. However, it can be distinguished from the latter by its unique procumbent life form, adventitious roots at nodes, papery leaves, cup-shaped or campanulate calyx, truncate or shallow fissure calyx lobes, and smaller fruits. In addition, the new species is also similar with C. basitruncata, a species only known from the original description and the photograph of holotype, but it can differ from the latter by its procumbent shrub, purple terete branchlets with apparent linear lenticels, adventitious roots at nodes, and papery larger leaves with prominently cordate leaf base. Original photographs, illustration, distribution map, and a comparative morphological table, as well as an identification key of the related taxa are provided.

13.
J Funct Biomater ; 14(2)2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36826888

RESUMEN

To evaluate the effects of airborne particle abrasion (APA) combined with MDP-containing resin cement, a glass-ceramic spray deposition (GCSD) method on the shear bond strengths (SBSs) and durability of 3 mol% yttrium oxide-stabilized zirconia ceramic (3Y-TZP) compared with lithium disilicate glass ceramics (LDGC). 3Y-TZP disks were randomly treated as follows: for Group APA+MDP, 3Y-TZP was abrased using 50 µm Al2O3 particles under 0.1 Mpa and bonded with MDP-containing resin cement; for Group GCSD, 3Y-TZP was treated with the GCSD method, etched by 5% HF for 90 s, silanized and bonded with resin cement without MDP. Group LDGC was bonded as the Group GCSD. X-ray diffraction (XRD), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and energy dispersive X-ray detector (EDX) were used to analyze the surface chemical and micro-morphological changes of the ceramics before bonding. The bonded ceramic specimens were randomly divided into subgroups, and the SBSs were determined before and after 10,000 thermocycling. The SBSs were analyzed with a one-way ANOVA analysis. Failure modes were determined with optical microscopy and SEM. The XRD, ATR-FTIR and XPS results identified the formation of lithium disilicate and zirconium silicate on 3Y-TZP after GCSD. The SEM micrographs revealed that 3Y-TZP surfaces were roughened by APA, while 3Y-TZP with GCSD and LDGC surfaces could be etched by HF to be porous. The APA treatment combined with MDP-containing resin cement produced the high immediate zirconia shear bond strengths (SBSs: 37.41 ± 13.51 Mpa) that was similar to the SBSs of the LDGC (34.87 ± 11.02 Mpa, p > 0.05), but, after thermocycling, the former dramatically decreased (24.00 ± 6.86 Mpa, maximum reduction by 35.85%) and the latter exhibited the highest SBSs (30.72 ± 7.97 Mpa, minimum reduction by 11.9%). The 3Y-TZP with GCSD treatment displayed the lower zirconia SBSs before thermocycling (27.03 ± 9.76 Mpa, p < 0.05), but it was similar to the 3Y-TZP treated with APA and MDP containing resin cement after thermocycling (21.84 ± 7.03 vs. 24.00 ± 6.86 Mpa, p > 0.05). The APA combined with MDP-containing resin cement could achieve the high immediate zirconia SBSs of those of the LDGC, but it decreased significantly after thermocycling. The GCSD technique could yield the immediate zirconia SBSs similar to those of LDGC before thermocycling, and long-term zirconia SBSs were similar to those of 3Y-TZP treated with APA followed by MDP-containing resin cement after thermocycling. Hence, the GCSD technique could enrich zirconia surface treatments and is an alternative to zirconia surface pretreatment for 3Y-TZP bond durability.

14.
Sheng Wu Gong Cheng Xue Bao ; 39(2): 755-768, 2023 Feb 25.
Artículo en Chino | MEDLINE | ID: mdl-36847103

RESUMEN

Production internship is an important teaching tache for undergraduate students to carry out engineering training by using professional skills, and it is a key starting point for fostering application-oriented talents in biotechnology. The Course Group of 'production internship of biotechnology majors' of Binzhou University is investigating application-oriented transformation for local regular colleges and universities, as well as fostering high-level application-oriented talents. By taking green fluorescent protein (GFP) polyclonal antibody as an example, the reform and practice on teaching content, teaching mode, assessment method, continuous improvement of curriculum were carried out. Moreover, the characteristics of the Yellow River Delta-Binzhou Biotechnology & Pharmaceutical Industrial Cluster were taken into account to intensify academic-enterprise cooperation. On one hand, this Course Group designed and rearranged the course contents, carried out essential training through online resources and platforms such as virtual simulation, and recorded, tracked and monitored the progress of production internship through practical testing and software platforms like 'Alumni State'. On the other hand, this Course Group established a practice-and application-oriented assessment method in the process of production internship and a dual evaluation model for continuous improvement. These reform and practices have promoted the training of application-oriented talents in biotechnology, and may serve as a reference for similar courses.


Asunto(s)
Internado y Residencia , Humanos , Curriculum , Estudiantes , Biotecnología
15.
J Agric Food Chem ; 71(1): 347-357, 2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36541437

RESUMEN

So far, the potential role of vitamin D in ß-cell function remains a matter of debate. Therefore, a randomized, placebo-controlled trial (RCT) was conducted to evaluate the effect of a vitamin D supplement with or without calcium on ß-cell function in a Chinese population with prediabetes. Two hundred and forty-three subjects were randomly assigned in a 2-by-2 factorial-design RCT to receive either 1600 IU/day vitamin D3 with/or 500 mg/day calcium for 24 weeks. The results showed that oral administration of vitamin D and calcium could increase the secretion of insulin. Vitamin D-insufficient individuals displayed an increment in the disposition index (adjusted change = 0.31, 95%CI: 0.07, 0.56) after treatment by vitamin D + calcium. It illustrated that supplementation with vitamin D and calcium might improve the function of pancreatic ß-cell in prediabetes with low serum 25(OH)D levels. However, further studies are needed to confirm the findings. Given the low vitamin D content in natural foods, it is necessary to fortify processed foods with vitamin D.


Asunto(s)
Resistencia a la Insulina , Células Secretoras de Insulina , Estado Prediabético , Humanos , Calcio , Calcio de la Dieta , Colecalciferol , Suplementos Dietéticos , Método Doble Ciego , Estado Prediabético/tratamiento farmacológico , Vitamina D , Vitaminas
16.
Appl Microbiol Biotechnol ; 107(2-3): 881-896, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36585512

RESUMEN

INTRODUCTION: Epsilon-poly-L-lysine (ε-PL) is produced by Streptomyces species in acidic and aerobic conditions, which inevitably induces rapid generation of reactive oxygen species (ROS). The devastating effects of ROS on biomolecules and cell vitality have been well-studied, while the positive effects of ROS are rarely reported. RESULTS: In this study, we found that a proper dose of intracellular ROS (about 3.3 µmol H2O2 /g DCW) could induce a physiological modification to promote the ε-PL production (from 1.2 to 1.5 g/L). It resulted in larger sizes of colony and mycelial pellets as well as vibrant, aggregated, and more robust mycelia, which were of high capability of ROS detoxication. Physiological studies showed that appropriate doses of ROS activated the metabolism of the pentose phosphate pathway at both transcriptional and enzymatic levels, which was beneficial for biomass accumulation. The biosynthesis of lysine was also promoted in terms of transcriptional regulatory overexpression, increased transcription and enzymatic activity of key genes, larger pools of metabolites in the TCA cycle, replenishment pathway, and diaminoheptanedioic acid pathway. In addition, energy provision was ensured by activated metabolism of the TCA cycle, a larger pool of NADH, and higher activity of the electron transport system. Increased transcription of HrdD and pls further accelerated the ε-PL biosynthesis. SIGNIFICANCE: These results indicated that ROS at proper intracellular dose could act as an inducing signal to activate the ε-PL biosynthesis, which laid a foundation for further process regulation to maintain optimal ROS dose in industrial ε-PL production and was of theoretical and practical significance. KEY POINTS: • A proper dose of intracellular ROS positively influences the ε-PL production. • Proper dose of ROS enhanced the mycelial activity and antioxidative capability. • ROS increased lysine synthesis metabolism, energy provision and pls expression.


Asunto(s)
Polilisina , Streptomyces , Especies Reactivas de Oxígeno/metabolismo , Peróxido de Hidrógeno/metabolismo , Streptomyces/genética , Ciclo del Ácido Cítrico
17.
Appl Environ Microbiol ; 88(20): e0095222, 2022 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-36190251

RESUMEN

ε-Poly-l-lysine (ε-PL) is a wide-spectrum antimicrobial agent, while its biosynthesis-inducing signals are rarely reported. This study found that Botrytis cinerea extracts could act as a microbial call to induce a physiological modification of Streptomyces albulus for ε-PL efficient biosynthesis and thereby resulted in ε-PL production (34.2 g/liter) 1.34-fold higher than control. The elicitors could be primary isolated by ethanol and butanol extraction, which resulted in more vibrant, aggregate and stronger mycelia. The elicitor-derived physiological changes focused on three aspects: ε-PL synthase, energy metabolism, and lysine biosynthesis. After elicitor addition, upregulated sigma factor hrdD and improved transcription and expression of pls directly contributed to the high ε-PL productivity; upregulated genes in tricarboxylic acid (TCA) cycle and energy metabolism promoted activities of citrate synthase and the electron transport system; in addition, pool enlargements of ATP, ADP, and NADH guaranteed the ATP provision for ε-PL assembly. Lysine biosynthesis was also increased based on enhancements of gene transcription, key enzyme activities, and intracellular metabolite pools related to carbon source utilization, the Embden-Meyerhof pathway (EMP), the diaminopimelic acid pathway (DAP), and the replenishment pathway. Interestingly, the elicitors stimulated the gene transcription for the quorum-sensing system and resulted in upregulation of genes for other antibiotic production. These results indicated that the Botrytis cinerea could produce inducing signals to change the Streptomyces mycelial physiology and accelerate the ε-PL biosynthesis. IMPORTANCE This work identified the role of microbial elicitors on ε-PL production and disclosed the underlying mechanism through analysis of gene transcription, key enzyme activities, and intracellular metabolite pools, including transcriptome and metabolome analysis. It was the first report for the inducing effects of the "microbial call" to Streptomyces albulus and ε-PL biosynthesis, and these elicitors could be potentially obtained from decayed fruits infected by Botrytis cinerea; hence, this may be a way of turning a biohazard into bioproduct wealth. This study provided a reference for application of microbial signals in secondary metabolite production, which is of theoretical and practical significance in industrial antibiotic production.


Asunto(s)
Polilisina , Transcriptoma , Adenosina Difosfato/metabolismo , Adenosina Trifosfato/metabolismo , Antibacterianos , Butanoles , Carbono , Citrato (si)-Sintasa/metabolismo , Ácido Diaminopimélico/metabolismo , Etanol , Fermentación , Sustancias Peligrosas , Metaboloma , NAD/metabolismo , Polilisina/metabolismo , Factor sigma/metabolismo , Ácidos Tricarboxílicos
18.
RSC Adv ; 12(28): 18181-18196, 2022 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-35800317

RESUMEN

The impacts of adding diluent gases (nitrogen, carbon dioxide, and helium) either to the fuel side or the oxidizer side on the sooting transition process in ethylene counterflow diffusion flames are investigated experimentally and numerically. A series of ethylene flames ranging from non-sooting to heavy-sooting are studied by gradually increasing the oxygen concentration on the oxidizer side. The optical method is used to analyze flame images, determining the sooting transition process. It is found that whether CO2 is added to the fuel side or the oxidizer side, the sooting transition process is delayed significantly. This process is slightly delayed when He is added to the fuel side, however, it is promoted when He is introduced to the oxidizer side. The numerical results show that in CO2-diluted flames, the mole fraction of the main soot precursors C2H2, C3H3, and C6H6 are reduced, which leads to the delay of soot formation. In addition, the H radical decreases while the OH radical increases, both of them are important for soot formation. In He-diluted flames, the concentration of C2H2, C3H3, and C6H6 decreased, as well as H and OH radicals. Moreover, adding He obviously changes the distribution area of products.

19.
Food Sci Biotechnol ; 31(7): 893-904, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35720462

RESUMEN

Foodborne pathogens causing food poisoning and infections are detrimental to human health, and the abuse of antibiotics induced severe antibiotic resistance in past decades. Thus, it is urgent to develop new antimicrobial agents. In the current study, human ß-defensin 130 (hBD130), which is an antimicrobial peptide identified in human macrophages in 2017, was initially produced in Pichia pastoris. The purified hBD130 demonstrated broad bactericidal spectrum against foodborne pathogens through a membrane disruption, with concentrations ranging from 10 to 45 µg/mL. Moreover, hBD130 showed a low hemolytic effect and nearly no cytotoxicity to mammalian cells with a dosage of 400 µg/mL. In addition, the secretion amounts and mRNA levels of NO, IL-6, IL-1ß, and TNF-α in LPS-induced mouse macrophage were significantly decreased with 1 mg/mL of hBD130. Taken together, these results showed that hBD130 is a promising antimicrobial agent to treat foodborne bacterial infections and inflammation. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-022-01087-y.

20.
Sheng Wu Gong Cheng Xue Bao ; 38(4): 1671-1684, 2022 Apr 25.
Artículo en Chino | MEDLINE | ID: mdl-35470637

RESUMEN

Bioengineering majors require students to acquire excellent abilities of thinking and analyzing complex problems and have high requirements for students' comprehensive practical skills. Because of the professional characteristics, it is necessary to develop students' abilities to solve complex problems via the teaching of a series of experiments. Therefore, it is particularly important to reform the traditional experiment teaching for students majoring in bioengineering to improve the teaching quality, which have great significance for the cultivation of comprehensive talents. In this study, with the advantages of geographical location and resources to cultivate application-oriented innovative talents, the course group of Comprehensive Experiment of Bioengineering has designed the course based on virtual simulation technology in Binzhou University. Taking the experiment of extraction and bioactivity analysis of Suaeda salsa (growing in the Yellow River Delta) polysaccharide in fermentation as a case, we studied the course design idea, experimental process, teaching method and result analysis, and have improved the teaching performance. This case analysis provides new ideas and content reference for the teaching reform of similar courses.


Asunto(s)
Ingeniería Biomédica , Estudiantes , Bioingeniería/educación , Ingeniería Biomédica/educación , Humanos , Tecnología , Universidades
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