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1.
J Environ Manage ; 368: 122137, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39153319

RESUMEN

Global warming is altering the frequency of extreme rainfall events and introducing uncertainties for non-point source pollution (NPSP). This research centers on orchard-influenced planting areas (OIPA) in the Wulong River Watershed of Shandong Province, China, which are known for their heightened nitrogen (N) and phosphorus (P) pollution. Leveraging meteorological data from both historical (1989-2018) and projected future periods (2041-2100), this research identified five extreme rainfall indices (ERI): R10 (moderate rain), R20 (heavy rain), R50 (rainstorm), R95p (Daily rainfall between the 95th and 99th percentile of the rainfall), and R99p (>99th percentile). Utilizing an advanced watershed hydrological model, SWAT-CO2, this study carried out a comparison between ERI and average conditions and evaluated the effects of ERI on the hydrology and nutrient losses in this coastal watershed. The findings revealed that the growth multiples of precipitation in the OIPA for five ERI varied between 16 and 59 times for the historical period and 14 to 65 times for future climate scenarios compared to the average conditions. The most pronounced increases in surface runoff and total phosphorus (TP) loss were observed with R50, R95p, and R99p, showing growth multiples as high as 352 and 330 times, and total nitrogen (TN) growth multiples varied between 4.6 and 30.3 times. The contribution rates of R50 and R99p for surface runoff and TP loss in the OIPA during all periods exceeded 55%, however, TN exhibited the opposite trend, primarily due to the dominated NO3-N leaching in the sandy soil. This research revealed how the OIPA reacts to different ERI and pinpointed essential elements influencing water and nutrient losses.

2.
Int Immunopharmacol ; 140: 112802, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39088924

RESUMEN

BACKGROUND: Formononetin (FNT) is an isoflavone known for its anti-inflammatory properties and has been shown to reduce insulin resistance in Type 2 Diabetes Mellitus (T2DM). However, its effects and the underlying mechanisms in diabetic liver injury remain largely unexplored. METHODS: We established a T2DM-induced liver injury mouse model by feeding high-fat diet, followed by injecting streptozotocin. The mice were then treated with FNT and the liver function in these mice was assessed. Macrophage markers in FNT-treated T2DM mice or human THP-1 cells were evaluated using flow cytometry, RT-qPCR, and Western blotting. The expression of PTP1B and STAT6 in mouse liver tissues and THP-1 cells was analyzed. Molecular docking predicted the interaction between PTP1B and STAT6, which was validated via co-immunoprecipitation (Co-IP) and phos-tag analysis. Microscale thermophoresis (MST) assessed the binding affinity of FNT to PTP1B. RESULTS: FNT treatment significantly ameliorated blood glucose levels, hepatocyte apoptosis, inflammatory response, and liver dysfunction in T2DM mice. Moreover, FNT facilitated M2 macrophage polarization in both T2DM mice and high glucose (HG)-induced THP-1-derived macrophages. The PTP1B/STAT6 axis, deregulated in T2DM mice, was normalized by FNT treatment, which counteracted the T2DM-induced upregulation of PTP1B and downregulation of phosphorylated STAT6. Molecular docking and subsequent analyses revealed that PTP1B binds to and dephosphorylates STAT6 at the S325A site. In contrast, FNT strongly binds to PTP1B and influences its expression at the K116A site, promoting M2 polarization of THP-1 cells via downregulation of PTP1B. CONCLUSION: Formononetin mitigates diabetic hepatic injury by fostering M2 macrophage polarization via the PTP1B/STAT6 axis.

3.
Water Res ; 265: 122279, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39178589

RESUMEN

Rising atmospheric carbon dioxide concentrations ([CO2]) affect crop growth and the associated hydrological cycle through physiological forcing, which is mainly regulated by reducing stomatal conductance (gs) and increasing leaf area index (LAI). However, reduced gs and increased LAI can affect crop water consumption, and the overall effects need to be quantified under elevated [CO2]. Here we develop a SWAT-gs-LAI model by incorporating a nonlinear gs-CO2 equation and a missing LAI-CO2 relationship to investigate the responses of water consumption of grain maize, maize yield, and losses of water and soil to elevated [CO2] in the Upper Mississippi River Basin (UMRB; 492,000 km2). Results exhibited enhanced maize yield with decreased water consumption for increases in [CO2] from 495 ppm to 825 ppm during the historical period (1985-2014). Elevated [CO2] promoted surface runoff but suppressed sediment loss as the predominant impact of LAI-CO2 leading to enhanced surface cover. A comprehensive analysis of future climate change showed increased maize water consumption in comparison to the historical period, driven by the more pronounced effects of overall climate change rather than solely elevated [CO2]. Generally, future climate change promoted maize yield in most regions of the UMRB for three Shared Socioeconomic Pathway (SSP) scenarios. Surface runoff was shown to increase generally in the future with sediment loss increasing by an average of 0.39, 0.42, and 0.66 ton ha-1 for SSP1-2.6, SSP2-4.5, and SSP5-8.5, respectively. This was due to negative climatic change effects largely surpassing the positive effect of elevated [CO2], particularly in zones near the middle and lower stream. Our results underscore the crucial role of employing a physically-based model to represent crop physiological processes under elevated [CO2] conditions, improving the reliability of predictions related to crop growth and the hydrological cycle.

4.
Environ Res ; 259: 119515, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38969318

RESUMEN

China is the largest global orchard distribution area, where high fertilization rates, complex terrain, and uncertainties associated with future climate change present challenges in managing non-point source pollution (NPSP) in orchard-dominant growing areas (ODGA). Given the complex processes of climate, hydrology, and soil nutrient loss, this study utilized an enhanced Soil and Water Assessment Tool model (SWAT-CO2) to investigate the impact of future climate on NPSP in ODGA in a coastal basin of North China. Our investigation focused on climate-induced variations in hydrology, nitrogen (N), and phosphorus (P) losses in soil, considering three Coupled Model Intercomparison Project phase 6 (CMIP6) climate scenarios: SSP1-2.6, SSP2-4.5, and SSP5-8.5. Research results indicated that continuous changes in CO2 levels significantly influenced evapotranspiration (ET) and water yield in ODGA. Influenced by sandy soils, nitrate leaching through percolation was the principal pathway for N loss in the ODGA. Surface runoff was identified as the primary pathway for P loss. Compared to the reference period (1971-2000), under three future climate scenarios, the increase in precipitation of ODGA ranged from 15% to 28%, while the growth rates of P loss and surface runoff were the most significant, both exceeding 120%. Orchards in the northwest basin proved susceptible to nitrate leaching, while others were more sensitive to N and P losses via surface runoff. Implementing targeted strategies, such as augmenting organic fertilizer usage and constructing terraced fields, based on ODGA's response characteristics to future climate, could effectively improve the basin's environment.

5.
J Perinat Med ; 52(1): 108-113, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-37936493

RESUMEN

OBJECTIVES: To investigate the function of circMyt1l/rno-let-7d-5p/BDNF in the white matter damage of premature rats. METHODS: Bioinformatic analysis was used to analyze the differential expression of circMyt1l and its interacting miRNAs and mRNAs in rats with periventricular white matter damage. Rats at postnatal day 3 had their right common carotid artery permanently ligated, and were then exposed for 2 h to 6 % O2, or sham surgery and exposure to normal O2 levels (sham). CircMyt1l and rno-let-7d-5p expression was detected and BDNF protein levels were analyzed at 24, 48, and 72 h post hypoxia-ischemia. RESULTS: Bioinformatic analysis suggested that circMyt1l, rno-let-7d-5p and BDNF interact. CircMyt1l expression decreased significantly relative to the sham-operated rats (p<0.01) in an exposure time-dependent manner. Contrastingly, rno-let-7d-5p increased significantly relative to the sham-operated rats (p<0.01) in an exposure time dependent manner. BDNF protein levels decreased significantly relative to the sham-operated rats (p<0.05) in an exposure time dependent manner. CONCLUSIONS: The expression levels of circMyt1l/rno-let-7d-5p/BDNF are interrelated in periventricular white matter damage. Decreased circMyt1l expression of promoted the effect of rno-let-7d-5p and decreased the level of its target, BDNF.


Asunto(s)
MicroARNs , Sustancia Blanca , Ratas , Animales , Animales Recién Nacidos , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/metabolismo , MicroARNs/metabolismo
6.
Front Public Health ; 11: 1284959, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38074765

RESUMEN

Background: Any form of physical activity is recommended for the older adults to maintain their physical function; however, the effect of daily activities on muscle function still needs to be investigated. Humans always use one dominant hand to perform tasks, providing a natural situation for research on the effect of daily activities on muscle function. Methods: Five hundred and twenty-six healthy adults were recruited from the community in Beijing. Muscle strength was assessed using a handgrip dynamometer, lean mass, fat mass, bone area and bone mineral content of upper limbs were assessed using dual-energy X ray-absorptiometry. The results were compared between the dominant and non-dominant upper limbs. Results: The dominant upper limb had better muscle strength, lean mass, bone area and bone mineral content than the non-dominant side. The difference in muscle strength and lean mass between the two upper limbs decreased with the advanced age. In older age, fat mass of upper limbs increased in men, but not in women. Conclusion: Daily activities can maintain better muscle function in the dominant upper limb than in the non-dominant side; however, the delaying effect on age-related decline in muscle function was limited.


Asunto(s)
Fuerza de la Mano , Músculo Esquelético , Masculino , Humanos , Femenino , Anciano , Músculo Esquelético/fisiología , Extremidad Superior , Densidad Ósea/fisiología , Fuerza Muscular/fisiología
7.
Front Public Health ; 11: 1281291, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38089027

RESUMEN

Background and objectives: Nationwide data were used to explore factors associated with physical function in order to identify interventions that could improve and maintain physical function in the older people. Methods: The physical function was assessed by gait speed (GS). We selected 2,677 male and 2,668 female older adults (aged ≥60) who could perform the GS test as study subjects. GS was measured by having subjects walk across and back a 10-m course. A gait speed less than 20% that of a reference population (<0.7 m/s) was used as the definition of slow gait speed (SGS). Co-morbidity, polypharmacy, medical expenses, need for care, and hospitalization were used to evaluate health status. A stepwise logistic regression model was used to determine factors associated with SGS. Results: SGS was associated with poorer health status, higher medical cost, lower ranking on the Geriatric Depression Scale (GDS) and decreased Mini-mental State Examination (MMSE). Co-morbidity (OR = 1.81, 1.58-2.07), polypharmacy (OR = 1.47, 1.25-1.74), MMSE <24 (OR = 1.85, 1.54-2.22), and GDS ≥ 11 (OR = 1.40, 1.18-1.65) were associated with SGS. In contrast, doing housework (DHW, OR = 0.43, 0.38-0.49), having a regular daily routine (RDR, OR = 0.64, 0.45-0.91), and current alcohol consumption (OR = 0.74, 0.62-0.90) were inversely associated with SGS. DHW plus having RDR could greatly reduce the risk of SGS (OR = 0.29, 0.19-0.43). Conclusion: Poor physical function is associated with poorer health status in Chinese older people. Maintaining a regular daily routine and doing some housework may be important factors that can help older people preserve their physical function.


Asunto(s)
Tareas del Hogar , Velocidad al Caminar , Humanos , Masculino , Femenino , Anciano , Comorbilidad , Estado de Salud , Consumo de Bebidas Alcohólicas
8.
Angew Chem Int Ed Engl ; 62(45): e202306305, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37522821

RESUMEN

Photocatalytic valorization and selective transformation of biomass-derived platform compounds offer great opportunities for efficient utilization of renewable resources under mild conditions. Here, the novel three-dimensional hierarchical flower-like CdS/Ti3 C2 Schottky junction (MCdS) composed of surface-controlled CdS and pretreated Ti3 C2 MXene is created for photocatalytic dehydrogenation-reductive amination of biomass-derived amino acid production under ambient temperature with unprecedented activity and selectivity. Schottky junction efficiently promotes photoexcited charge migration and separation and inhibits photogenerated electron-hole recombination, which results in a super-high activity. Meanwhile, CdS with the reduced surface energy supplies sufficient hydrogen sources for imine reduction and induces the preferential orientation of alanine, thus contributing superior selectivity. Moreover, a wide range of hydroxyl acids are successfully converted into corresponding amino acids and even one-pot conversion of glucose to alanine is easily achieved over MCdS. This work illustrates the mechanism of crystal orientation control and heterojunction construction in controlling catalytic behavior of photocatalytic nanoreactor, providing a paradigm for construction of MXene-based heterostructure.

9.
Front Oncol ; 11: 704001, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34381726

RESUMEN

Chemoresistance is the primary reason for the poor prognosis of patients with ovarian cancer, and the search for a novel drug treatment or adjuvant chemotherapy drug is an urgent need. The tumor microenvironment plays key role in the incidence and development of tumors. As one of the most important components of the tumor microenvironment, M2 tumor-associated macrophages are closely related to tumor migration, invasion, immunosuppressive phenotype and drug resistance. Many studies have confirmed that triptolide (TPL), one of the principal components of Tripterygium wilfordii, possesses broad-spectrum anti-tumor activity. The aims of this study were to determine whether TPL could inhibit the migration and invasion of A2780/DDP cells in vitro and in vivo by inhibiting the polarization of M2 tumor-associated macrophages (TAMs); to explore the mechanism(s) underlying TPL effects; and to investigate the influence of TPL on murine intestinal symbiotic microbiota. In vitro results showed that M2 macrophage supernatant slightly promoted the proliferation, invasion, and migration of A2780/DDP cells, which was reversed by TPL in a dose-dependent manner. Animal experiments showed that TPL, particularly TPL + cisplatin (DDP), significantly reduced the tumor burden, prolonged the life span of mice by inhibiting M2 macrophage polarization, and downregulated the levels of CD31 and CD206 (CD31 is the vascular marker and CD206 is the macrophage marker), the mechanism of which may be related to the inhibition of the PI3K/Akt/NF-κB signaling pathway. High-throughput sequencing results of the intestinal microbiota in nude mice illustrated that Akkermansia and Clostridium were upregulated by DDP and TPL respective. We also found that Lactobacillus and Akkermansia were downregulated by DDP combined with TPL. Our results highlight the importance of M2 TAMs in Epithelial Ovarian Cancer (EOC) migration ability, invasiveness, and resistance to DDP. We also preliminarily explored the mechanism governing the reversal of the polarization of M2 macrophages by TPL.

10.
Front Microbiol ; 12: 643422, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34220737

RESUMEN

Vaginal microbiota dysbiosis, characterized by the loss of Lactobacillus dominance and increase of microbial diversity, is closely related to gynecological diseases; thus, intervention on microbiota composition is significant and promising in the treatment of gynecological diseases. Currently, antibiotics and/or probiotics are the mainstay of treatment, which show favorable therapeutic effects but also bring problems such as drug resistance and high recurrence. In this review, we discuss the role of vaginal microbiota dysbiosis in various gynecological infectious and non-infectious diseases, as well as the current and potential interventions.

11.
Artículo en Inglés | MEDLINE | ID: mdl-34068331

RESUMEN

Particulate pollution caused by urban traffic emissions has become a significant public hazard. Many urban roads of under-viaduct spaces (UVSs) have become concentrated areas of particulate pollution. This study aims to explore the effects of landscape parameters on particulate matter in UVSs in Wuhan, China. We selected 14 types of UVS sections and nine potential environmental parameters to monitor four types of particulate matter (PM1.0, PM2.5, PM10, and TSP). Finally, linear regression analysis was employed to quantify the relative contributions of environmental parameters to the reduction in the concentration of the four types of particulate matter in the summer and winter. The results showed that particulate matter concentrations exhibit spatial and seasonal differences in UVSs. A single landscape parameter was correlated with particulate matter concentration, while compound environmental parameters had significant effects on the particulate matter concentration in UVSs. Meteorological factors and greening structures had a dominant impact on the particulate matter concentrations in summer and winter, respectively. Therefore, adjusting and optimizing the environmental parameters could reduce particulate pollution in UVSs and could have practical significance for the planning and design of UVSs.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , China , Monitoreo del Ambiente , Material Particulado/análisis , Estaciones del Año
12.
BMC Genomics ; 22(1): 196, 2021 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-33740891

RESUMEN

BACKGROUND: MicroRNAs play an important role in many fundamental biological and pathological processes. Defining the microRNAs profile underlying the processes by beneficial and detrimental lifestyles, including caloric restriction (CR), exercise and high-fat diet (HF), is necessary for understanding both normal physiology and the pathogenesis of metabolic disease. We used the microarray to detect microRNAs expression in livers from CR, EX and HF mice models. After predicted potential target genes of differentially expressed microRNAs with four algorithms, we applied GO and KEGG to analyze the function of predicted microRNA targets. RESULTS: We describe the overall microRNAs expression pattern, and identified 84 differentially expressed microRNAs changed by one or two or even all the three lifestyle modifications. The common and different enriched categories of gene function and main biochemical and signal transduction pathways were presented. CONCLUSIONS: We provided for the first time a comprehensive and thorough comparison of microRNAs expression profiles in liver among these lifestyle modifications. With this knowledge, our findings provide us with an overall vision of microRNAs in the molecular impact of lifestyle on health as well as useful clues for future and thorough research of the role of microRNAs.


Asunto(s)
Hígado , MicroARNs , Animales , Dieta Alta en Grasa/efectos adversos , Perfilación de la Expresión Génica , Estilo de Vida , Ratones , MicroARNs/genética , Transducción de Señal
13.
Crit Rev Biotechnol ; 41(4): 580-593, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33550854

RESUMEN

Ergothioneine is a sulfur-containing histidine derivative, that possessesexcellent antioxidant activity and has been used in the food and cosmetics industries. It plays a significant role in anti-aging and the prevention of various diseases. This review will briefly introduce the functions and applications of ergothioneine, elaborate the biosynthetic pathways of ergothioneine and describe several strategies to increase the production of ergothioneine. Then the efficient extraction and detection methods of ergothioneine will be presented. Finally, several proposals are put forward to increase the yield of ergothioneine, and the development prospects of ergothioneine will be discussed.


Asunto(s)
Ergotioneína , Antioxidantes , Vías Biosintéticas , Biotecnología , Ergotioneína/metabolismo , Histidina/metabolismo
14.
Int J Antimicrob Agents ; 57(3): 106277, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33434677

RESUMEN

Vaginal dysbiosis is characterised by a disturbed vaginal microbiota and is associated with various gynaecological diseases. Owing to its high recurrence rate, there is an urgent need for the development of effective therapeutic agents. In the present study, a vaginal dysbiosis model was developed to study the effect of vaginal microbiota transplantation (VMT) or probiotic combination (containing Lactobacillus helveticus, Lactobacillus crispatus, Lactobacillus acidophilus, Lactobacillus gasseri and Lactobacillus salivarius) on vaginal dysbiosis. Our results indicated that VMT or probiotic combination significantly reduced bacterial-induced inflammation (infiltration of neutrophils, lymphocytes and monocytes) in the uterine wall and the enrichment of pro-inflammatory cytokines [interleukin-1ß (IL-1ß) and tumour necrosis factor-alpha (TNFα)] in vaginal tissue, and restored the disturbed vaginal microbiota to normal levels (increased numbers of Lactobacillus and decreased numbers of Enterobacter and Enterococcus), thus it should be beneficial for avoiding the recurrence of vaginal dysbiosis. Therefore, VMT or probiotic combination might be an effective agent for the treatment of bacterial-induced vaginosis.


Asunto(s)
Disbiosis/terapia , Microbiota , Probióticos/uso terapéutico , Vagina/microbiología , Vaginosis Bacteriana/microbiología , Vaginosis Bacteriana/terapia , Adulto , Animales , Biodiversidad , Citocinas/metabolismo , ADN Bacteriano/genética , Modelos Animales de Enfermedad , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , ARN Ribosómico 16S/genética , Ratas , Ratas Sprague-Dawley , Vagina/patología
15.
Phys Rev Lett ; 127(27): 270602, 2021 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-35061422

RESUMEN

Non-Bloch topological invariants preserve the bulk-boundary correspondence in non-Hermitian topological systems, and are a key concept in the contemporary study of non-Hermitian topology. Here we report the dynamic detection of non-Bloch topological invariants in single-photon quantum walks, revealed through the biorthogonal chiral displacement, and crosschecked with the dynamic spin textures in the generalized quasimomentum-time domain following a quantum quench. Both detection schemes are robust against symmetry-preserving disorders, and yield consistent results with theoretical predictions. Our experiments are performed far away from any boundaries, and therefore underline non-Bloch topological invariants as intrinsic properties of the system that persist in the thermodynamic limit. Our work sheds new light on the experimental investigation of non-Hermitian topology.

16.
AMB Express ; 10(1): 80, 2020 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-32333225

RESUMEN

Alzheimer's disease (AD) and Parkinson's disease (PD) are neurodegenerative diseases (NDD) characterized by progressive degeneration of the central nervous system, and few medications are available to halt the progression of AD and PD. In the present study, an engineered strain MG136-pMG36e-GLP-1 was used to evaluate its neuroprotective effect on AD and PD mice, via the probiotics effects of Lactococcus lactis MG1363 and the constantly produced Glucagon-like peptide-1 (GLP-1) by the engineered strain. Our results indicated that oral administration of MG136-pMG36e-GLP-1 significantly reduced lipopolysaccharide (LPS)-induced memory impairment and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced motor dysfunction through the toll-like receptor4 (TLR4)/nuclear factor-kappa B (NFκB) and protein kinase B (AKT)/Glycogen synthase kinase-3ß (GSK3ß) signaling pathway. High-throughput sequencing results showed that MG1363-pMG36e-GLP-1 reduced the abundance of the pathogens Enterococcus, Proteus, and increased the abundance of the probiotics Akkermansia muciniphila. These results suggest that the engineered strain may be a new intervention for treating AD and PD by reducing the occurrence of neuroinflammation.

17.
Front Med (Lausanne) ; 7: 73, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32181256

RESUMEN

Background: Bowel preparation is necessary for successful colonoscopy, while it can seriously affect intestinal microbial composition and damage the intestinal mucosal barriers in humans. Methods: To figure out whether probiotics can sustain intestinal homeostasis and guard people's health, the probiotic drug of Bifidobacterium Tetragenous viable Bacteria Tablets (P group, n = 16) or placebo (C group, n = 16) was used for volunteers receiving bowel preparation, and high-throughput sequencing method was applied to monitor their intestinal microbial changes. Results: The present results suggested that bowel preparation obviously reduced the intestinal microbial diversity, while taking probiotics significantly restored it to normal level. In addition, probiotics sharply reduced the abundance of pathogenic Proteobacteria, and obviously lowered the ratio of Firmicutes/Bacteroidetes compared with control group at phylum level (P < 0.05). And probiotics markedly decreased the abundance of pathogenic Acinetobacter and Streptococcus, while greatly enriched the relative abundance of beneficial bacteria Bacteroides, Roseburia, Faecalibacterium, and Parabacteroides at genus level (P < 0.05). Conclusion: Probiotic drugs, e.g., Bifidobacterium Tetragenous viable Bacteria Tablets, can be used to restore intestinal dysbacteriosis caused by bowel preparation, and reduce side effects during colonoscopy.

18.
Biotechnol Adv ; 39: 107453, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31629792

RESUMEN

Vitamin K2, also called menaquinone, is an essential lipid-soluble vitamin that plays a critical role in blood clotting and prevention of osteoporosis. It has become a focus of research in recent years and has been widely used in the food and pharmaceutical industries. This review will briefly introduce the functions and applications of vitamin K2 first, after which the biosynthesis pathways and enzymes will be analyzed in-depth to highlight the bottlenecks facing the microbial vitamin K2 production on the industrial scale. Then, various strategies, including strain mutagenesis and genetic modification, different cultivation modes, fermentation and separation processes, will be summarized and discussed. The future prospects and perspectives of microbial menaquinone production will also be discussed finally.


Asunto(s)
Vitamina K 2/metabolismo , Vías Biosintéticas , Industria Farmacéutica , Fermentación
19.
Aging Med (Milton) ; 2(4): 190-197, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34553106

RESUMEN

BACKGROUND: Decline in cognition and in locomotion is associated with aging. However, the relationship between them and the current occurrence of them in Chinese elderly people was weak. METHODS: To investigate the details of these two functions in Chinese elderly people and to try to find some early recognition and intervention clues, data of MMSE test and usual gait speed from 4487 elderly people from seven provinces in China were analysed. RESULTS: The prevalence of mild cognitive impairment (MCI) and dementia in persons aged 60 and over was 17.83% and 4.08%, respectively. Among 11 items of MMSE, calculation, three-word recall, drawing two pentagons, and temporal orientation were the most commonly impaired items in persons with MCI or dementia. The gait speed of old persons with dementia was significantly slower than that of persons with MCI or NCI. Meanwhile, old persons with gait speed >1.39 m/s fast gait speed also had high MMSE scores and no dementia was detected by MMSE. CONCLUSION: The prevalence of dementia observed in this population was similar to that reported 20 years ago. Loss of temporal orientation and drawing two pentagons may supply more information for early recognition of cognitive impairment. Maintaining locomotion in a proper way may help old persons to prevent cognitive function decline.

20.
Sci Total Environ ; 633: 426-432, 2018 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-29579653

RESUMEN

Conversion of levulinic acid (LA) to γ-valerolactone (GVL) over a ruthenium-carbon (Ru/C) catalyst using formic acid (FA) as the sole hydrogen source in cellulose hydrolysis process was investigated. The reaction was accelerated using Ru(5wt%)/C as the catalyst and by adding triethylamine. The highest LA conversion (87.26%) and GVL yield (80.75%) were obtained using 10g/mol (LA) catalyst and 150mL/mol (LA) triethylamine at 160°C for 180min. In this reaction, the hydrogenation process can only be accomplished in the presence of FA, which is the byproduct of LA production from cellulose hydrolysis. The application of this new route not only improves the economy of the process, but also avoids the energy-costly separation of LA from the LA and FA aqueous mixture. A new reaction pathway for the conversion of LA and FA into GVL over Ru/C with triethylamine was proposed.

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