GLP-2 ameliorates D-galactose induced muscle aging by IGF-1/Pi3k/Akt/FoxO3a signaling pathway in C2C12 cells and mice.

BACKGROUND: The study aimed to investigate the effect of Glucagon-like peptide-2 (GLP-2) on muscle aging in vivo and in vitro. METHODS: Six-week-old C57BL/6J mice were administered with D-galactose (200 mg/kg/day, intraperitoneally) for 8weeks, followed by daily subcutaneous injections of GLP-2 (300 or 600 µg/kg/day) for 4weeks. Skeletal muscle function and mass were evaluated using relative grip strength and muscle weight. The sizes and types of muscle fibers and apoptosis were assessed through histological analysis, immunofluorescence staining, and TUNEL staining, respectively. C2C12 myotubes were treated with D-galactose (40 mg/mL) and GLP-2. Protein expression of differentiation-related myogenic differentiation factor D (MyoD), myogenin (MyoG), and myosin heavy chain (Myhc), degradation-related Muscle RING finger 1 (MuRF-1), and muscle atrophy F-box (MAFbx)/Atrogin-1, and apoptosis-related B-cell leukemia/lymphoma 2 (Bcl-2) and Bax, were assessed using western blots. The Pi3k inhibitor LY294002 was applied to investigate whether GLP-2 regulated myogenesis and myotube aging via IGF-1/Pi3k/Akt/FoxO3a signaling pathway. RESULTS: The results demonstrated that GLP-2 significantly reversed the decline in muscles weight, relative grip strength, diameter, and cross-sectional area of muscle fibers induced by D-galactose in mice. Apart from suppressing the expressions of MuRF-1 and Atrogin-1 in the muscles and C2C12 myotubes, GLP-2 significantly increased the expressions of MyoD, MyoG, and Myhc compared to the D-galactose. GLP-2 significantly suppressed cell apoptosis. Western blot analysis indicated that the regulation of GLP-2 may be attributed to the activation of theIGF-1/Pi3k/Akt/FoxO3a phosphorylation pathway. CONCLUSIONS: This study suggested that GLP-2 ameliorated D-galactose induced muscle aging by IGF-1/Pi3k/Akt/FoxO3a pathway.

Identification of hyperthermophilic D-allulose 3-epimerase from Thermotoga sp. and its application as a high-performance biocatalyst for D-allulose synthesis.

D-Allulose 3-epimerase (DAE) is a vital biocatalyst for the industrial synthesis of D-allulose, an ultra-low calorie rare sugar. However, limited thermostability of DAEs hinders their use at high-temperature production. In this research, hyperthermophilic TI-DAE (Tm = 98.4 ± 0.7 ℃) from Thermotoga sp. was identified via in silico screening. A comparative study of the structure and function of site-directed saturation mutagenesis mutants pinpointed the residue I100 as pivotal in maintaining the high-temperature activity and thermostability of TI-DAE. Employing TI-DAE as a biocatalyst, D-allulose was produced from D-fructose with a conversion rate of 32.5%. Moreover, TI-DAE demonstrated excellent catalytic synergy with glucose isomerase CAGI, enabling the one-step conversion of D-glucose to D-allulose with a conversion rate of 21.6%. This study offers a promising resource for the enzyme engineering of DAEs and a high-performance biocatalyst for industrial D-allulose production.

Transient social-ecological dynamics reveal signals of decoupling in a highly disturbed Anthropocene landscape.

Understanding the transient dynamics of interlinked social-ecological systems (SES) is imperative for assessing sustainability in the Anthropocene. However, how to identify critical transitions in real-world SES remains a formidable challenge. In this study, we present an evolutionary framework to characterize these dynamics over an extended historical timeline. Our approach leverages multidecadal rates of change in socioeconomic data, paleoenvironmental, and cutting-edge sedimentary ancient DNA records from China's Yangtze River Delta, one of the most densely populated and intensively modified landscapes on Earth. Our analysis reveals two significant social-ecological transitions characterized by contrasting interactions and feedback spanning several centuries. Initially, the regional SES exhibited a loosely connected and ecologically sustainable regime. Nevertheless, starting in the 1950s, an increasingly interconnected regime emerged, ultimately resulting in the crossing of tipping points and an unprecedented acceleration in soil erosion, water eutrophication, and ecosystem degradation. Remarkably, the second transition occurring around the 2000s, featured a notable decoupling of socioeconomic development from ecoenvironmental degradation. This decoupling phenomenon signifies a more desirable reconfiguration of the regional SES, furnishing essential insights not only for the Yangtze River Basin but also for regions worldwide grappling with similar sustainability challenges. Our extensive multidecadal empirical investigation underscores the value of coevolutionary approaches in understanding and addressing social-ecological system dynamics.

[Accumulation of microbial necromass carbon and their contribution to soil organic carbon in different vegetation types on the Loess Plateau, Northwest China]. / é»„åœŸé«˜åŽŸä¸åŒæ¤è¢«ç±»åž‹åœŸå£¤å¾®ç”Ÿç‰©æ®‹ä½“ç¢³çš„ç§¯ç´¯åŠå ¶å¯¹æœ‰æœºç¢³çš„è´¡çŒ®.

Microbial necromass carbon (MNC) is an important contributor to soil organic carbon (SOC). Soil carbon storage has increased significantly since the return of farmland to forestland (grassland) on the Loess Plateau. However, the contribution of MNC to SOC accumulation in different vegetation types and the influence factors remain unclear. Herein, we used the biomarker (amino sugar) technique to determine the MNC content and analyzed the influencing factors in 0-5 cm and 5-20 cm soil layers of natural grassland, shrubland (Caragana microphylla), and forestland (Quercus liaodongensis) in the Loess Plateau. The results showed that: 1) the soil pH decreased significantly from grassland to shrubland and then to forestland within the same soil layer. However, the SOC, total nitrogen (TN), microbial biomass carbon (MBC), and microbial biomass nitrogen (MBN) contents showed a reverse trend, with forestland displaying the highest values followed by shrubland and then grassland. The 0-5 cm had significantly higher values than the 5-20 cm depth. 2) The MNC contents varied 0.69-16.41 g·kg-1 in the two soil horizons of the three vegetation types. There were significant increases in the contents of bacterial necromass carbon (BNC), fungal necromass carbon (FNC), and MNC in the 0-5 cm soil from grassland, shrubland to forestland. The contents of MBC were 1.9 times higher in forestland than in shrubland, and 3.2 times higher in shrubland than in grassland. In the 5-20 cm soil layer, the contents of FNC and MBC were significantly higher in the forestland than in the shrubland and grassland. The FNC content was significantly higher than that of the BNC, ranging from 1.16 to 9.83 times greater than the BNC. 3) The contribution of MNC to SOC was 0.6 and 0.7 times higher in shrubland and forestland than in grassland, respectively, with FNC accounting for 15.2%-42.7%, and BNC accounting for 1.4%-7.4%. 4) pH, TN, MBC, and MBN were important factors that influenced MNC accumulation. In summary, the variation in vegetation type altered soil nutrients, microbial activity, and soil pH, resulting in forestland and shrubland being more beneficial to the formation and accumulation of MNC, which was dominated by fungi, compared to grassland.

Modification of nitrilase based on computer screening and efficient biosynthesis of 4-cyanobenzoic acid.

4-cyanobenzoic acid serves as a crucial intermediate for the synthesis of various high-value organic compounds. The enzymatic hydrolysis of terephthalonitrile to produce 4-cyanobenzoic acid using nitrilase offers the advantages of a simple reaction pathway, environmental friendliness, and easy product separation. In order to efficiently develop nitrilases that meet industrial production requirements, the virtual screening method used in the study is established and mature. From a total of 371 amino acids in the nitrilase AfNIT, which exhibits activity in terephthalonitrile hydrolysis, three candidate sites (F168, S192, and T201) were identified, and a "small and accurate" mutant library was constructed. The triple mutant F168V/T201N/S192F was screened from this small mutant library with a specific activity of 227.3 U mg-1 , which was 3.8 times higher than that of the wild-type AfNIT. Using the whole-cell biocatalyst containing the mutant F168V/T201N/S192F, terephthalonitrile was successfully hydrolyzed at a concentration of 150 g L-1 to produce 4-cyanobenzoic acid with a final yield of 170.3 g L-1 and a conversion rate of 98.7%. The obtained nitrilase mutant F168V/T201N/S192F in this study can be effectively applied in the biomanufacturing of 4-cyanobenzoic acid using terephthalonitrile as a substrate. Furthermore, the results also demonstrate the significant improvement in predictive accuracy achieved through the latest AI-assisted computer simulation methods. This approach represents a promising and feasible new technological pathway for assisting enzyme engineering research, laying a theoretical foundation for other related studies.

Analysis of risk factors and interactions for pain in temporomandibular disorder: A cross-sectional study.

BACKGROUND: Risk factors for temporomandibular disorder (TMD) pain remain unclear. OBJECTIVES: This study aimed to identify risk factors for TMD pain using a biopsychosocial model and to investigate interactions between potential risk factors-oral behaviours (OBs), psychological factors and sleep quality-and their direct and indirect effects on TMD pain. METHODS: This was a cross-sectional study of 488 patients with TMDs (422 women; 30.8 ± 9.4 years). Pain was assessed using the Numerical Rating Scale. Demographic, behavioural, psychological and biomedical data were collected through clinical examination, face-to-face interviews and questionnaires. Multiple linear regression analysis was used to identify factors associated with TMD pain. Mediation and moderation analysis were used to evaluate interactions between variables. Significant mediation ('0' not included in the 95% confidence interval (CI)) and moderation (p < .05) effects on TMD pain were identified. RESULTS: Marital status, diagnosis subgroup, previous medication use, depression and sleep quality were significant risk factors for TMD pain (p < .05). Significant mediation effects were observed as follows: depression and sleep quality mediated the association between OBs and pain; sleep quality mediated the association between somatization, depression, anxiety and pain; and depression mediated the association between sleep quality and pain (all 95% CI did not contain '0'). CONCLUSIONS: (1) Marital status, diagnosis subgroup, previous medication use, depression and sleep quality were associated with TMD pain. (2) OBs can exacerbate pain by promoting depression and reducing sleep quality. Psychological factors and sleep quality can interact to exacerbate pain.

Combined associations of cognitive impairment and psychological resilience with all-cause mortality in community-dwelling older adults.

BACKGROUND: Cognitive impairment and psychological resilience are closely related in older adults, but their combined effect on mortality has not been reported. Using a nationally representative sample from the Chinese Longitudinal Healthy Longevity Study, this study examined the interactions between cognitive impairment and psychological resilience and their associations with overall survival. METHODS: A total of 32,349 community-dwelling older adults (86.85 ± 11.16 years, 56.06 % female) were enrolled in 1998, 2000, 2002, 2005, 2008, 2011, and 2014; all participants were followed until 2018. Cognitive function and psychological resilience were assessed using the Mini-Mental State Examination (MMSE) and the 7-item psychological resilience questionnaire (PRQ), respectively. Illiterate subjects with an MMSE score <18, or literate subjects with an MMSE score <24 were defined as having cognitive impairment. Cox proportional risk regressions were used to analyze the association of cognitive impairment and psychological resilience with all-cause mortality. RESULTS: After 146,993.52 person-years of follow-up, 23,349 older adults died. Both MMSE and PRQ scores (as continuous variables) were negatively associated with mortality risk after adjusting for all covariates. The hazard ratio (HR) of all-cause mortality for cognitive impairment was not significantly moderated by levels of psychological resilience (P-interaction = 0.094). In joint analyses, participants with combined cognitive impairment and low resilience (by the median of PRQ: < 25 points) had the highest risk of mortality (adjusted-HR: 1.56, 95%CI: 1.48-1.61), which was higher than that of patients with either condition alone. There was a significant additive interaction effect of cognitive impairment and low resilience on all-cause mortality (relative excess risk due to interaction: 0.11, 95 % CI: 0.09-0.13), and 7 % of the overall mortality risk was attributable to their synergistic effect. CONCLUSIONS: Cognitive impairment and low resilience are synergistically associated with increased risk of all-cause mortality in community-dwelling older adults. The potential mechanisms underlying this combined effect warrant further exploration.

Atomic Engineering of Single-Atom Nanozymes for Biomedical Applications.

Single-atom nanozymes (SAzymes) showcase not only uniformly dispersed active sites but also meticulously engineered coordination structures. These intricate architectures bestow upon them an exceptional catalytic prowess, thereby captivating numerous minds and heralding a new era of possibilities in the biomedical landscape. Tuning the microstructure of SAzymes on the atomic scale is a key factor in designing targeted SAzymes with desirable functions. This review first discusses and summarizes three strategies for designing SAzymes and their impact on reactivity in biocatalysis. The effects of choices of carrier, different synthesis methods, coordination modulation of first/second shell, and the type and number of metal active centers on the enzyme-like catalytic activity are unraveled. Next, a first attempt is made to summarize the biological applications of SAzymes in tumor therapy, biosensing, antimicrobial, anti-inflammatory, and other biological applications from different mechanisms. Finally, how SAzymes are designed and regulated for further realization of diverse biological applications is reviewed and prospected. It is envisaged that the comprehensive review presented within this exegesis will furnish novel perspectives and profound revelations regarding the biomedical applications of SAzymes.

Construction of an instrument to enable the assessment of the risk of falls in older outpatients: A quantitative methodological study.

OBJECTIVES: To develop an instrument to facilitate the risk assessment of falls in older outpatients. DESIGN: A quantitative methodological study using the cross-sectional data. METHODS: This study enrolled 1988 older participants who underwent comprehensive geriatric assessment (CGA) in an outpatient clinic from May 2020 to November 2022. The history of any falls (≥1 falls in a year) and recurrent falls (≥2 falls in a year) were investigated. Potential risk factors of falls were selected by stepwise logistic regression, and a screening tool was constructed based on nomogram. The tool performance was compared with two reference tools (Fried Frailty Phenotype; CGA with 10 items, CGA-10) by using receiver operating curves, sensitivity (Sen), specificity (Spe), and area under the curve (AUC). RESULTS: Age, unintentional weight loss, depression measured by the Patient Health Questionnaire-2, muscle strength measured by the five times sit-to-stand test, and stand balance measured by semi- and full-tandem standing were the most important risk factors for falls. A fall risk screening tool was constructed with the six measurements (FRST-6). FRST-6 showed the best AUC (Sen, Spe) of 0.75 (Sen = 0.72, Spe = 0.69) for recurrent falls and 0.65 (Sen = 0.74, Spe = 0.48) for any falls. FRST-6 was comparable to CGA-10 and outperformed FFP in performance. CONCLUSIONS: Age, depression, weight loss, gait, and balance were important risk factors of falls. The FRST-6 tool based on these factors showed acceptable performance in risk stratification. IMPACT: Performing a multifactorial assessment in primary care clinics is urgent for falls prevention. The FRST-6 provides a simple and practical way for falls risk screening. With this tool, healthcare professionals can efficiently identify patients at risk of falling and make appropriate recommendations in resource-limited settings. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution was received, due to our study design.

Combined effects of vitamin D deficiency and systemic inflammation on all-cause mortality and cause-specific mortality in older adults.

BACKGROUND: Vitamin D deficiency and systemic inflammation share common pathological mechanisms in muscle loss, cardio-pulmonary function decline, and abnormal metabolism, which are linked to chronic conditions, senescence, and early mortality. However, their combined effect on mortality in older adults has not been well established. This study longitudinal aimed to explore the independent and combined associations of serum 25-hydroxyvitamin D [25(OH)D] and high sensitivity C-reactive protein (hs-CRP) with mortality risk in Chinese community-based older people. METHODS: 3072 older adults (86.07 ± 11.87 years, 54.52% female) from the Chinese Longitudinal Healthy Longevity Survey (2012-2018) were enrolled. Baseline 25(OH)D and hs-CRP levels were collected, and survival information was recorded in the 2014 and 2018 follow-up waves. Cox proportional hazard regressions were conducted to explore the associations between 25(OH)D, hs-CRP, and mortality. Demographic characteristics, health behaviors, and chronic disease biomarkers were adjusted. RESULTS: During 10,622.3 person-years of follow-up (median: 3.51 years), 1321 older adults died, including 448 deaths due to cardiovascular disease (CVD). Increased mortality risk was associated with lower 25(OH)D and higher hs-CRP quantiles, even after adjusting for each other and multiple covariates (all P-trend < 0.05). In combined analyses, the highest all-cause mortality (HR: 2.18, 95% CI: 1.73 ~ 2.56), CVD mortality (HR: 2.30, 95% CI: 1.64 ~ 3.21), and non-CVD mortality (HR: 2.19, 95% CI: 1.79 ~ 2.49) were obtained in participants with both 25(OH)D deficiency (< 50 nmol/L) and high hs-CRP (≥ 3.0 mg/L), respectively. We observed significant additive interactions of 25(OH)D and hs-CRP on all-cause mortality and non-CVD mortality (RERIS>0). CONCLUSIONS: Low 25(OH)D and high hs-CRP, both independently and jointly, increase mortality risk in Chinese community-dwelling older adults. Thus, priority should be given to early detection and appropriate intervention in older individuals with combined vitamin D deficiency and systemic inflammation. Molecular mechanisms of related adverse health effect are worthy of further investigation.

Sahara's surface transformation forced an abrupt hydroclimate decline and Neolithic culture transition in northern China.

The remote forcing from land surface changes in the Sahara is hypothesized to play a pivotal role in modulating the intensity of the East Asian summer monsoon (EASM) through ocean-atmospheric teleconnections. This modulation has far-reaching consequences, particularly in facilitating societal shifts documented in northern China. Here, we present a well-dated lake-level record from the Daihai Lake Basin in northern China, providing quantitative assessments of Holocene monsoonal precipitation and the consequent migrations of the northern boundary of the EASM. Our reconstruction, informed by a water-and-energy balance model, indicates that annual precipitation reached ∼700 mm during 8-5 ka, followed by a rapid decline to ∼550 mm between 5 and 4 ka. This shift coherently aligns with a significant ∼300 km northwestward movement of the EASM northern boundary during the Middle Holocene (MH), in contrast to its current position. Our findings underscore that these changes cannot be entirely attributed to orbital forcing, as corroborated by simulation tests. Climate model simulations deployed in our study suggest that the presence of the Green Sahara during the MH significantly strengthened the EASM and led to a northward shift of the monsoon rainfall belt. Conversely, the Sahara's reversion to a desert landscape in the late Holocene was accompanied by a corresponding southward retraction of monsoon influence. These dramatic hydroclimate changes during ∼5-4 ka likely triggered or at least contributed to a shift in Neolithic cultures and societal transformation in northern China. With decreasing agricultural productivity, communities transitioned from millet farming to a mixed rainfed agriculture and animal husbandry system. Thus, our findings elucidate not only the variability of the EASM but also the profound implications of a remote forcing, such as surface transformations of the Sahara, on climatic changes and cultural evolution in northern China.

Household polluting cooking fuels and intrinsic capacity among older population: A harmonized nationwide analysis in India and China.

BACKGROUNDS: Household polluting cooking fuels, as an important changeable behavior, are related to various detrimental health effects among the elderly. There is limited research on the association between polluting cooking fuel use and intrinsic capacity (IC) as an indicator of healthy aging. This study aimed to evaluate the above-mentioned association in India and China, where polluting cooking fuel use is common. METHODS: We enrolled 33,803 participants aged ≥60 years from two nationally representative studies: the Longitudinal Aging Study in India and the China Health and Retirement Longitudinal Study. Polluting cooking fuel use was defined as a self-report of using wood, coal, kerosene, crop residue, or dung. IC was measured by five aspects, including locomotion, cognition, vitality, sensory, and psychological capacity. The random-effects mixed linear regression and logistic regression with population weighting were performed. Multivariable-adjusted model and propensity score were used to adjust for potential confounders. RESULTS: A total of 47.54 % and 59.32 % of elderly adults reported primary cooking using polluting fuels in India and China, respectively. Using polluting cooking fuels was consistently associated with IC decline; particularly, cognitive capacity was the most susceptible domain. In India, participants using polluting fuels had a 1.062 (95 % confidence interval [CI]: 1.047-1.078) times risk for IC deficits, whereas more prominent results were observed in China (odds ratio [OR]: 2.040, 95 % CI: 1.642-2.533). Such harmful effects might be alleviated by transferring from polluting to clean fuels. Additionally, the duration of polluting fuel use was also positively associated with IC deficits. CONCLUSION: This study provided substantial public implications on healthy aging for the elderly population at a global scale, strengthening the importance of health education and policy efforts to accelerate the transition from polluting to clean fuels.

Highly efficient production of rhamnolipid in P. putida using a novel sacB-based system and mixed carbon source.

Pseudomonas putida KT2440, a GRAS strain, has been used for synthesizing bulk and fine chemicals. However, the gene editing tool to metabolically engineer KT2440 showed low efficiency. In this study, a novel sacB-based system pK51mobsacB was established to improve the efficiency for marker-free gene disruption. Then the rhamnolipid synthetic pathway was introduced in KT2440 and genes of the competitive pathways were deleted to lower the metabolic burden based on pK51mobsacB. A series of endogenous and synthetic promoters were used for fine tuning rhlAB expression. The limited supply of dTDP-L-rhamnose was enhanced by heterologous rmlBDAC expression. Cell growth and rhamnolipid production were well balanced by using glucose/glycerol as mixed carbon sources. The final strain produced 3.64 g/L at shake-flask and 19.77 g/L rhamnolipid in a 5 L fermenter, the highest obtained among metabolically engineered KT2440, which implied the potential of KT2440 as a promising microbial cell factory for industrial rhamnolipid production.

Self-Trapped, Thermally Equilibrated Delayed Fluorescence Enables Low-Reabsorption Luminescent Solar Concentrators Based on Gold-Doped Silver Nanoclusters.

Reabsorption-free luminescent solar concentrators (LSCs) are crucial ingredients for photovoltaic windows. Atomically precise metal nanoclusters (NCs) with large Stokes-shifted photoluminescence (PL) hold great promise for applications in LSCs. However, a fundamental understanding of the PL mechanism, particularly on the excited-state interaction and exciton kinetics, is still lacking. Herein, we studied the exciton-phonon coupling and singlet/triplet exciton dynamics for gold-doped silver NCs in a solid matrix. Following photoexcitation, the excitons can be self-trapped via strong exciton-phonon coupling. Subsequently, rapid thermal equilibration between the singlet and triplet states occurs due to the coexistence of small energy splitting and spin-orbit coupling. Finally, broadband delayed fluorescence with a large Stokes shift can be generated, namely, self-trapped, thermally equilibrated delayed fluorescence (ST-TEDF). Benefiting from superior ST-TEDF, we demonstrated efficient LSCs with minimized reabsorption.

RNF13 protects against pathological cardiac hypertrophy through p62-NRF2 pathway.

Heart failure (HF) severely impairs human health because of its high incidence and mortality. Cardiac hypertrophy is the main cause of HF, while its underlying mechanism is not fully clear. As an E3 ubiquitin ligase, Ring finger protein 13 (RNF13) plays a crucial role in many disorders, such as liver immune, neurological disease and tumorigenesis, whereas the function of RNF13 in cardiac hypertrophy remains largely unknown. In the present study, we found that the protein expression of RNF13 is up-regulated in the transverse aortic constriction (TAC)-induced murine hypertrophic hearts and phenylephrine (PE)-induced cardiomyocyte hypertrophy. Functional investigations indicated that RNF13 global knockout mice accelerates the degree of TAC-induced cardiac hypertrophy, including cardiomyocyte enlargement, cardiac fibrosis and heart dysfunction. On the contrary, adeno-associated virus 9 (AAV9) mediated-RNF13 overexpression mice alleviated cardiac hypertrophy. Furthermore, we demonstrated that adenoviral RNF13 attenuates the PE-induced cardiomyocyte hypertrophy and down-regulates the expression of cardiac hypertrophic markers, while the opposite results were observed in the RNF13 knockdown group. The RNA-sequence of RNF13 knockout and wild type mice showed that RNF13 deficiency activates oxidative stress after TAC surgery. In terms of the mechanism, we found that RNF13 directly interacted with p62 and promoted the activation of downstream NRF2/HO-1 signaling. Finally, we proved that p62 knockdown can reverse the effect of RNF13 in cardiac hypertrophy. In conclusion, RNF13 protects against the cardiac hypertrophy via p62-NRF2 axis.

Mixed Plastics Wastes Upcycling with High-Stability Single-Atom Ru Catalyst.

Mixed plastic waste treatment has long been a significant challenge due to complex composition and sorting costs. In this study, we have achieved a breakthrough in converting mixed plastic wastes into a single chemical product using our innovative single-atom catalysts for the first time. The single-atom Ru catalyst can convert ∼90% of real mixed plastic wastes into methane products (selectivity >99%). The unique electronic structure of Ru sites regulates the adsorption energy of mixed plastic intermediates, leading to rapid decomposition of mixed plastics and superior cycle stability compared to traditional nanocatalysts. The global warming potential of the entire process was evaluated. Our proposed carbon-reducing process utilizing single-atom catalysts launches a new era of mixed plastic waste valorization.

Platelet-rich plasma therapy for temporomandibular joint osteoarthritis: A randomized controlled trial.

The study aimed to compare the efficacy of platelet-rich plasma (PRP) injections for the treatment of temporomandibular joint osteoarthritis (TMJ-OA) with hyaluronic acid (HA) therapy. This randomized controlled trial included 70 patients with TMJ-OA, randomly divided into either a PRP or HA group. The pain intensity, maximum mouth opening (MMO), TMJ sound score, and proportion of crepitus were recorded and compared at baseline and at 1, 3, and 6 months. Both groups showed statistically significant improvements in pain intensity, MMO, TMJ sound, and scale scores during the 6-month follow-up period. The improvements in pain intensity during mouth opening at 1 month, MMO at 1, 3, and 6 months, TMJ sound score at 1 and 3 months, and GAD-7 score at 6 months in the PRP group were greater than in the HA group (p < 0.05). Compared with the HA group, imaging improvement in the PRP group was also higher (p < 0.05). Within the limitations of the study it seems that the application of PRP therapy in TMJ-OA is should be considered whenever possible.

Anthropogenic activities altering the ecosystem in Lake Yamzhog Yumco, southern Qinghai-Tibetan Plateau.

Lakes on the Qinghai-Tibet Plateau (QTP) have been subject to multiple environmental pressures from rapid climate change and intensified human activity in recent decades. However, their ecological effects on the lake ecosystem remain largely unclear due to the lack of long-term monitoring data. This study presented the environmental and ecological changes of the lake Yamzhog Yumco (Southern QTP) over the past three decades based on multi-proxy analysis (geochemistry and sedaDNA) on a high-time resolution sediment core. The result showed that the lake exhibited a continuous eutrophication process from 2004 CE, which has accelerated since 2014 CE. The nutrient enrichment was mainly attributed to anthropogenic emissions from the catchment. The sedimentary ancient DNA (sedaDNA) metabarcoding data registered a sensitive response of aquatic communities to the additional nutrient supply. Eukaryotic algae and aquatic invertebrate communities exhibited similar temporal dynamics, characterized by the increase in eutrophic taxa and the decrease in oligotrophic taxa. Change points analysis suggested that lake ecosystems underwent a slight ecological shift in 2003 CE and an abrupt shift in 2012 CE driven by nutrient enrichment. Quantitative analysis revealed that nutrients and human activity accounted for 27.9 % and 21.7 % of the temporal variation in aquatic communities, whereas climate change only explained 6.9 % of the total variation. From a paleolimnological view, our study supported that regional human activity could distinctly alter the nutrient level and aquatic community structure of lake ecosystems in the QTP. Considering that anthropogenic disturbance will continuously increase, it is crucial to strengthen the field monitoring of the lakes on the plateau and make effective management measures to avoid irreversible ecological consequences.

Secretory production of 7-dehydrocholesterol by engineered Saccharomyces cerevisiae.

BACKGROUND: 7-Dehydrocholesterol (7-DHC) can be directly converted to vitamin D3 by UV irradiation and de novo synthesis of 7-DHC in engineered Saccharomyces cerevisiae has been recognized as an attractive substitution to traditional chemical synthesis. Introduction of sterol extracellular transport pathway for the secretory production of 7-DHC is a promising approach to achieve higher titer and simplify the downstream purification processing. METHODS AND RESULTS: A series of genes involved in ergosterol pathway were combined reinforced and reengineered in S. cerevisiae. A biphasic fermentation system was introduced and 7-DHC was found to be enriched in oil-phase with an increased titer by 1.5-folds. Quantitative PCR revealed that say1, atf2, pdr5, pry1-3 involved in sterol storage and transport were all significantly induced in sterol overproduced strain. To enhance the secretion capacity, lipid transporters of pathogen-related yeast proteins (Pry), Niemann-Pick disease type C2 (NPC2), ATP-binding cassette (ABC)-family, and their homologues were screened. Both individual and synergetic overexpression of Plant pathogenesis Related protein-1 (Pr-1) and Sterol transport1 (St1) largely increased the de novo biosynthesis and secretory productivity of 7-DHC, and the final titer reached 28.2 mg g-1 with a secretion ratio of 41.4%, which was 26.5-folds higher than the original strain. In addition, the cooperation between Pr-1 and St1 in sterol transport was further confirmed by confocal microscopy, molecular docking, and directed site-mutation. CONCLUSION: Selective secretion of different sterol intermediates was characterized in sterol over-produced strain and the extracellular export of 7-DHC developed in present study significantly improved the cell biosynthetic capacity, which offered a novel modification idea for 7-DHC de novo biosynthesis by S. cerevisiae cell factory.

Controllable and complete conversion of agarose into oligosaccharides and monosaccharides by microwave-assisted hydrothermal and enzymatic hydrolysis and antibacterial activity of agaro-oligosaccharides.

Hydrolysis of agar or agarose can yield two types of oligosaccharides: agaro-oligosaccharides (AOS) and neoagaro-oligosaccharides (NAOS). These oligosaccharides have various biological activities and promising applications in the future food industry and pharmaceuticals. In this study, we prepared AOS from agarose by microwave-assisted hydrothermal hydrolysis and then used a commercial ß-galactosidase to treat AOS for producing NAOS. A complete conversion from agarose to AOS or NAOS can be achieved by microwave hydrothermal treatment and one-step enzyme reaction, and the production process was completely green. In addition, we combined ß-galactosidase and α-neoagarobiose hydrolase from Saccharophagus degradans 2-40 (SdNABH) to treat AOS, and AOS was completely converted into monosaccharides. Then the results of the inhibitory activity of AOS on the growth of Streptococcus mutans showed that AOS might be a good potential sugar substitute for dental caries prevention. This study provides an efficient approach for the production of multiple mixed degrees of polymerization (DP) of pure AOS and NAOS without requiring acid catalyst and agarases while simplifying the production processes and reducing costs.