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Lysosomes are degradation centers of cells and intracellular hubs of signal transduction, nutrient sensing, and autophagy regulation. Dysfunction of lysosomes contributes to a variety of diseases, such as lysosomal storage diseases (LSDs) and neurodegeneration, but the mechanisms are not well understood. Altering lysosomal activity and examining its impact on the occurrence and development of disease is an important strategy for studying lysosome-related diseases. However, methods to dynamically regulate lysosomal function in living cells or animals are still lacking. Here, we constructed lysosome-localized optogenetic actuators, named lyso-NpHR3.0, lyso-ArchT, and lyso-ChR2, to achieve optogenetic manipulation of lysosomes. These new actuators enable light-dependent control of lysosomal membrane potential, pH, hydrolase activity, degradation, and Ca2+ dynamics in living cells. Notably, lyso-ChR2 activation induces autophagy through the mTOR pathway, promotes Aß clearance in an autophagy-dependent manner in cellular models, and alleviates Aß-induced paralysis in the Caenorhabditis elegans model of Alzheimer's disease. Our lysosomal optogenetic actuators supplement the optogenetic toolbox and provide a method to dynamically regulate lysosomal physiology and function in living cells and animals.
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Péptidos beta-Amiloides , Autofagia , Caenorhabditis elegans , Lisosomas , Optogenética , Lisosomas/metabolismo , Autofagia/fisiología , Optogenética/métodos , Animales , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiología , Péptidos beta-Amiloides/metabolismo , Humanos , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/genética , Calcio/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Concentración de Iones de Hidrógeno , Células HEK293 , Células HeLaRESUMEN
n-Caproic acid is a widely used biochemical that can be produced from organic waste through chain elongation technology. This study aims to evaluate the environmental impacts of n-caproic acid production through chain elongation by two processes (i.e., shunting and staged technology). The Open-life cycle assessment (LCA) model was used to calculate the environmental impacts of both technologies based on experimental data. Results showed that the shunting technology had higher environmental impacts than the staged technology. Water and electricity made bigger contribution to the environmental impacts of both technologies. Reusing chain elongation effluent substituting for water and using electricity produced by wind power could reduce the environmental impacts of water and electricity effectively. Using ethanol from food waste had higher global warming potential than fossil ethanol, which suggested that a cradle-to-grave LCA is needed to be carried out for specific raw materials and chain elongation products in the future.
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Ambiente , Alimento Perdido y DesperdiciadoRESUMEN
Aiming to address the issues of parameter complexity and high computational load in existing fault detection algorithms for transmission lines, which hinder their deployment on devices like drones, this study proposes a novel lightweight model called Leaner YOLOv7-Tiny. The primary goal is to swiftly and accurately detect typical faults in transmission lines from aerial images. This algorithm inherits the ELAN structure from YOLOv7-Tiny network and replaces its backbone with depthwise separable convolutions to reduce model parameters. By integrating the SP attention mechanism, it fuses multi-scale information, capturing features across various scales to enhance small target recognition. Finally, an improved FCIoU Loss function is introduced to balance the contribution of high-quality and low-quality samples to the loss function, expediting model convergence and boosting detection accuracy. Experimental results demonstrate a 20% reduction in model size compared to the original YOLOv7-Tiny algorithm. Detection accuracy for small targets surpasses that of current mainstream lightweight object detection algorithms. This approach holds practical significance for transmission line fault detection.
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In the face of complex scenarios, the information insufficiency of classification tasks dominated by a single modality has led to a bottleneck in classification performance. The joint application of multimodal remote sensing data for surface observation tasks has garnered widespread attention. However, issues such as sample differences between modalities and the lack of correlation in physical features have limited the performance of classification tasks. Establishing effective interaction between multimodal data has become another significant challenge. To fully integrate heterogeneous information from multiple modalities and enhance classification performance, this paper proposes a dual-branch cross-Transformer feature fusion network aimed at joint land cover classification of hyperspectral imagery (HSI) and Light Detection and Ranging (LiDAR) data. The core idea is to leverage the potential of convolutional operators to represent spatial features, combined with the advantages of the Transformer architecture in learning remote dependencies. The framework employs an improved self-attention mechanism to aggregate features within each modality, highlighting the spectral information of HSI and the spatial (elevation) information of LiDAR. The feature fusion module based on cross-attention integrates deep features from two modalities, achieving complementary information through cross-modal attention. The classification task is performed using jointly obtained spectral and spatial features. Experiments were conducted on three multi-source remote sensing classification datasets, demonstrating the effectiveness of the proposed model compared to existing methods.
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AIM: To describe the lived experiences of family caregivers of individuals with dementia during the coronavirus disease (COVID-19) outbreak in China. DESIGN: This study used a descriptive phenomenological research method. METHODS: Between May and September 2021, semi-structured interviews were conducted with 22 family caregivers of people with dementia. Colaizzi's method was used for manual analysis. RESULTS: Qualitative data revealed an overarching experience of finding 'There is always good fortune in misfortune to encourage us in coping with difficulties'. Three themes emerged: family reactions to the COVID-19 outbreak, feeling supported by multiple resources performing respective functions and resilient adaptation to new situations. CONCLUSION: During the COVID-19 outbreak, family caregivers of people living with dementia in China looked for positive aspects among difficulties and experienced corresponding reactions, social support resources and resilient adapted coping styles. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: Nurses in China and other countries facing similar pandemic characteristics, cultures or economic development levels, can guide family caregivers to look at family hardships from a positive perspective, develop interventions to rapidly respond to families' reactions after a disaster and help them identify social support resources and form adapted coping styles. IMPACT: We identified the resilience and the positive experiences of Chinese family caregivers of individuals with dementia during the COVID-19 outbreak. The results can inform countries with similar cultures and economic levels, offering measures to support their adaptation to pandemics. REPORTING METHOD: This study followed the COREQ guidelines. PATIENT OR PUBLIC CONTRIBUTION: Family caregivers of people with dementia who met the inclusion criteria and who were interested in sharing their understanding of their experiences, participated in the study.
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COVID-19 , Demencia , Humanos , Cuidadores , COVID-19/epidemiología , Investigación Cualitativa , Habilidades de Afrontamiento , China/epidemiología , Brotes de Enfermedades , Demencia/epidemiología , FamiliaRESUMEN
Dextransucrases play a crucial role in the production of dextran from economical sucrose; therefore, there is a pressing demand to explore novel dextransucrases with better performance. This study characterized a dextransucrase enzyme, LmDexA, which was identified from the Leuconostoc mesenteroides NN710. This bacterium was isolated from the soil of growing dragon fruit in Guangxi province, China. We successfully constructed six different N-terminal truncated variants through sequential analysis. Additionally, a truncated variant, ΔN190LmDexA, was constructed by removing the 190 amino acids fragment from the N-terminal. This truncated variant was then successfully expressed heterologously in Escherichia coli and purified. The purified ΔN190LmDexA demonstrated optimal hydrolysis activity at a pH of 5.6 and a temperature of 30 °C. Its maximum specific activity was measured to be 126.13 U/mg, with a Km of 13.7 mM. Results demonstrated a significant improvement in the heterologous expression level and total enzyme activity of ΔN190LmDexA. ΔN190LmDexA exhibited both hydrolytic and transsaccharolytic enzymatic activities. When sucrose was used as the substrate, it primarily produced high-molecular-weight dextran (>400 kDa). However, upon the addition of maltose as a receptor, it resulted in the production of a significant amount of oligosaccharides. Our results can provide valuable information for enhancing the characteristics of recombinant dextransucrase and potentially converting sucrose into high-value-added dextran and oligosaccharides.
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Clonación Molecular , Glucosiltransferasas , Leuconostoc mesenteroides , Glucosiltransferasas/genética , Glucosiltransferasas/metabolismo , Glucosiltransferasas/química , Leuconostoc mesenteroides/enzimología , Leuconostoc mesenteroides/genética , Dextranos/química , Dextranos/biosíntesis , Dextranos/metabolismo , Hidrólisis , Concentración de Iones de Hidrógeno , Escherichia coli/genética , Mutación , Especificidad por Sustrato , Sacarosa/metabolismo , Cinética , TemperaturaRESUMEN
BACKGROUND: Late embryogenesis abundant (LEA) proteins play an important role in dehydration process of seed maturation. The seeds of Panax notoginseng (Burkill) F. H. Chen are typically characterized with the recalcitrance and are highly sensitive to dehydration. However, it is not very well known about the role of LEA proteins in response to dehydration stress in P. notoginseng seeds. We will perform a genome-wide analysis of the LEA gene family and their transcriptional responses to dehydration stress in recalcitrant P. notoginseng seeds. RESULTS: In this study, 61 LEA genes were identified from the P. notoginseng genome, and they were renamed as PnoLEA. The PnoLEA genes were classified into seven subfamilies based on the phylogenetic relationships, gene structure and conserved domains. The PnoLEA genes family showed relatively few introns and was highly conserved. Unexpectedly, the LEA_6 subfamily was not found, and the LEA_2 subfamily contained 46 (75.4%) members. Within 19 pairs of fragment duplication events, among them 17 pairs were LEA_2 subfamily. In addition, the expression of the PnoLEA genes was obviously induced under dehydration stress, but the germination rate of P. notoginseng seeds decreased as the dehydration time prolonged. CONCLUSIONS: We found that the lack of the LEA_6 subfamily, the expansion of the LEA_2 subfamily and low transcriptional levels of most PnoLEA genes might be implicated in the recalcitrant formation of P. notoginseng seeds. LEA proteins are essential in the response to dehydration stress in recalcitrant seeds, but the protective effect of LEA protein is not efficient. These results could improve our understanding of the function of LEA proteins in the response of dehydration stress and their contributions to the formation of seed recalcitrance.
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Panax notoginseng , Panax notoginseng/genética , Panax notoginseng/metabolismo , Deshidratación/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Filogenia , Semillas/metabolismo , Desarrollo Embrionario , Regulación de la Expresión Génica de las PlantasRESUMEN
BACKGROUND: Panax notoginseng (Burk) F.H. Chen is an essential plant in the family of Araliaceae. Its seeds are classified as a type of morphophysiological dormancy (MPD), and are characterized by recalcitrance during the after-ripening process. However, it is not clear about the molecular mechanism on the after-ripening in recalcitrant seeds. RESULTS: In this study, exogenous supply of gibberellic acid (GA3) with different concentrations shortened after-ripening process and promoted the germination of P. notoginseng seeds. Among the identified plant hormone metabolites, exogenous GA3 results in an increased level of endogenous hormone GA3 through permeation. A total of 2971 and 9827 differentially expressed genes (DEGs) were identified in response to 50 mg L-1 GA3 (LG) and 500 mg L-1 GA3 (HG) treatment, respectively, and the plant hormone signal and related metabolic pathways regulated by GA3 was significantly enriched. Weighted gene co-expression network analysis (WGCNA) revealed that GA3 treatment enhances GA biosynthesis and accumulation, while inhibiting the gene expression related to ABA signal transduction. This effect was associated with higher expression of crucial seed embryo development and cell wall loosening genes, Leafy Contyledon1 (LEC1), Late Embryogenesis Abundant (LEA), expansins (EXP) and Pectinesterase (PME). CONCLUSIONS: Exogenous GA3 application promotes germination and shorts the after-ripening process of P. notoginseng seeds by increasing GA3 contents through permeation. Furthermore, the altered ratio of GA and ABA contributes to the development of the embryo, breaks the mechanical constraints of the seed coat and promotes the protrusion of the radicle in recalcitrant P. notoginseng seeds. These findings improve our knowledge of the contribution of GA to regulating the dormancy of MPD seeds during the after-ripening process, and provide new theoretical guidance for the application of recalcitrant seeds in agricultural production and storage.
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Panax notoginseng , Plantas Medicinales , Reguladores del Crecimiento de las Plantas , Germinación , SemillasRESUMEN
PURPOSE: The Radiofrequency (RF)-induced heating for an active implantable medical device (AIMD) with dual parallel leads is evaluated in this paper. The coupling effects between dual parallel leads are studied via simulations and experiments methods. The global transfer function technique is used to assess the RF-induced heating for dual-lead AIMDs inside four human body models. METHODS: RF-induced heating for spinal cord stimulator systems with 60 and 90 cm length leads are studied at three parallel dual-lead configurations (closely spaced, 8 mm spaced, and 40 mm spaced) and a single-lead configuration. The global transfer function method is used to develop the AIMD models of different configurations and is used for lead-tip heating assessments inside human body models. RESULTS: In simulation studies, the peak 1g specific absorption rate/temperatrue rises of dual parallel leads systems is lower than those from the single-lead system. In experimental American Society for Testing and Materials phantom studies, the temperature rises for the single-lead AIMD system can be 2.4 times higher than that from dual-lead AIMD systems. For the spinal cord stimulator systems used in the study, the statistical analysis shows the RF-induced heating of dual-lead configurations are also lower than those from the single-lead configuration inside all four human body models. CONCLUSION: For the AIMD system in this study, it shows that the coupling effects between the dual parallel leads of AIMD systems can reduce RF-induced heating. The global transfer function for different spatial distance dual-lead configurations can potentially provide a method for the RF-induced heating evaluation for dual-lead AIMD systems.
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Calefacción , Prótesis e Implantes , Humanos , Simulación por Computador , Temperatura , Fantasmas de Imagen , Imagen por Resonancia Magnética/métodos , Ondas de Radio , CalorRESUMEN
BACKGROUND: Resveratrol is a commercially available stilbenoid widely used as dietary supplements, functional food ingredients, and cosmetic ingredients due to its diverse physiological activities. The production of resveratrol in microorganisms provides an ideal source that reduces the cost of resveratrol, but the titer in Saccharomyces cerevisiae was still much lower than that in other hosts. RESULTS: To achieve enhanced production of resveratrol in S. cerevisiae, we constructed a biosynthetic pathway via combining phenylalanine and tyrosine pathways by introducing a bi-functional phenylalanine/tyrosine ammonia lyase from Rhodotorula toruloides. The combination of phenylalanine pathway with tyrosine pathway led to a 462% improvement of resveratrol production in yeast extract peptone dextrose (YPD) medium with 4% glucose, suggesting an alternative strategy for producing p-coumaric acid-derived compounds. Then the strains were further modified by integrating multi-copy biosynthetic pathway genes, improving metabolic flux to aromatic amino acids and malonyl-CoA, and deleting by-pathway genes, which resulted in 1155.0 mg/L resveratrol in shake flasks when cultured in YPD medium. Finally, a non-auxotrophic strain was tailored for resveratrol production in minimal medium without exogenous amino acid addition, and the highest resveratrol titer (4.1 g/L) ever reported was achieved in S. cerevisiae to our knowledge. CONCLUSIONS: This study demonstrates the advantage of employing a bi-functional phenylalanine/tyrosine ammonia lyase in the biosynthetic pathway of resveratrol, suggesting an effective alternative in the production of p-coumaric acid-derived compounds. Moreover, the enhanced production of resveratrol in S. cerevisiae lays a foundation for constructing cell factories for various stilbenoids.
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Saccharomyces cerevisiae , Tirosina , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Resveratrol/metabolismo , Tirosina/metabolismo , Fenilalanina/metabolismo , Fenilanina Amoníaco-Liasa/genética , Fenilanina Amoníaco-Liasa/metabolismo , Ingeniería Metabólica/métodosRESUMEN
The overexpression of polysialic acid (polySia) on neural cell adhesion molecules (NCAM) promotes hypersialylation, and thus benefits cancer cell migration and invasion. It has been proposed that the binding between the polysialyltransferase domain (PSTD) and CMP-Sia needs to be inhibited in order to block the effects of hypersialylation. In this study, CMP was confirmed to be a competitive inhibitor of polysialyltransferases (polySTs) in the presence of CMP-Sia and triSia (oligosialic acid trimer) based on the interactional features between molecules. The further NMR analysis suggested that polysialylation could be partially inhibited when CMP-Sia and polySia co-exist in solution. In addition, an unexpecting finding is that CMP-Sia plays a role in reducing the gathering extent of polySia chains on the PSTD, and may benefit for the inhibition of polysialylation. The findings in this study may provide new insight into the optimal design of the drug and inhibitor for cancer treatment.
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Movimiento CelularRESUMEN
Baiyangdian wetland is the biggest plant-dominated shallow freshwater wetland in Huabei Plain, providing a wide range of ecosystem services. In the past few decades, the water scarcity and eco-environmental problems resulted from climate changes and human activities have become more and more serious. To relieve the pressure of water scarcity and ecological degradation, the government has implemented ecological water diversion projects (EWDPs) since 1992. In this study, land use and land cover change (LUCC) caused by EWDPs over three decades was analyzed to quantitatively assess the impact of EWDPs on ecosystem services. Coefficients of ecosystem service value (ESV) calculation were improved for regional ESV evaluation. The results showed that the area of construction, farmland and water increased by 6171, 2827, 1393 ha, respectively, and the total ESV increased by 8.04 × 108 CNY primarily due to the increase of regulating service with water area expansion. Redundancy analysis and socio-economic comprehensive analysis showed that EWDPs impacted water area and ESV with threshold and time effect. When the water diversion exceeded the threshold, the EWDPs affected the ESV through influencing LUCC; otherwise, the EWDPs affected the ESV through influencing net primary productivity or social-economic benefits. However, the impact of EWDPs on ESV gradually weakened as time passed, which could not keep sustainability. With the establishment of Xiong'an New Area in China and implementation of carbon neutrality policy, rational EWDPs will become crucial to achieve goals of ecological restoration.
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Ecosistema , Humedales , Humanos , Agua , Conservación de los Recursos Naturales , ChinaRESUMEN
PURPOSE: The paper presents a novel method to reduce the RF-induced heating of active implantable medical devices during MRI. METHODS: With the addition of an energy decoying and dissipating structure, RF energy can be redirected toward the dissipating rings through the decoying conductor. Three lead groups (45 cm-50 cm) and 4 (50 cm-100 cm) were studied in 1.5 Tesla MR systems by simulation and measurement, respectively. In vivo modeling was performed using human models to estimate the RF-induced heating of an active implantable medical device for spinal cord treatment. RESULT: In the simulation study, it was shown that the peak 1g-averaged specific absorption rate near the lead-tips can be reduced by 70% to 80% compared to those from the control leads. In the experimental measurements during a 2-min exposure test in a 1.5 Telsa MR system, the temperature rises dropped from the original 18.3â, 25.8â, 8.1â, and 16.1â (control leads 1-4) to 5.4â, 6.9â, 1.6â, and 3.3â (leads 1-4 with the energy decoying and dissipation structure). The in vivo calculation results show that the maximum induced temperature rise among all cases can be substantially reduced (up to 80%) when the energy decoying and dissipating structures were used. CONCLUSION: Our studies confirm the effectiveness of the novel technique for a variety of scanning scenarios. The results also indicate that the decoying conductor length, number of rings, and ring area must be carefully chosen and validated.
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Calefacción , Ondas de Radio , Simulación por Computador , Calor , Humanos , Imagen por Resonancia Magnética , Fantasmas de Imagen , Prótesis e ImplantesRESUMEN
PURPOSE: During MR scans, abandoned leads from active implantable medical devices (AIMDs) can experience excessive heating at the lead tip, depending on the type of termination applied to the proximal contacts (proximal end treatment). The influence of different proximal end treatments (ie, [1] freely exposed in the tissue, [2] terminated with metal in contact with the tissue, or [3] capped with plastic, and thereby fully insulated, on the RF-induced lead-tip heating) are studied. A technique to ensure that MR Conditional AIMD leads remain MR Conditional even when abandoned is recommended. METHODS: Abandoned leads from three MR Conditional AIMDs ([1] a sacral neuromodulation system, [2] a cardiac rhythm management pacemaker system, and [3] a deep brain stimulator system) were investigated in this study. The computational lead models (ie, the transfer functions) for different proximal end treatments were measured and used to assess the in vivo lead-tip heating for four virtual human models (FATS, Duke, Ella, and Billie) and compared with the lead-tip heating of the complete MR Conditional AIMD system. RESULT: The average and maximum lead-tip heating for abandoned leads proximally capped with metal is always lower than that from the complete AIMD system. Abandoned leads proximally insulated could lead to an average in vivo temperature rise up to 3.5 times higher than that from the complete AIMD system. CONCLUSION: For the three investigated AIMDs under 1.5T MR scanning, our results indicate that RF-induced lead-tip heating of abandoned leads strongly depends on the proximal lead termination. A metallic cap applied to the proximal termination of the tested leads could significantly reduce the RF-induced lead-tip heating.
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Imagen por Resonancia Magnética , Prótesis e Implantes , Calefacción , Humanos , Espectroscopía de Resonancia Magnética , Fantasmas de Imagen , Prótesis e Implantes/efectos adversos , Ondas de RadioRESUMEN
OBJECTIVE: This study aimed to investigate the associations between loneliness and its components and cognitive function among older Chinese adults living in nursing homes and to test whether depressive symptoms, anxiety symptoms, and sleep disturbances mediate these associations. METHODS: The sample comprised 228 Chinese individuals aged ≥ 65 years living in nursing homes who were free of dementia and psychiatric or serious somatic diseases. Loneliness was evaluated using the UCLA Loneliness Scale. Global cognitive function was assessed using the Beijing version of the Montreal Cognitive Assessment. Multivariable linear regression analyses were performed to examine the associations between loneliness and its components and global cognitive function. A mediation analysis was used to test the potential mediating effects of depressive symptoms, anxiety symptoms, and sleep disturbances. RESULTS: The mean (SD) age of the participants was 80.8 (6.3) years, and 58.3% were women. Compared with the lowest quartile of loneliness degree, the multivariable-adjusted beta coefficient (95% confidence interval [95% CI]) for the highest quartile was -1.32 (-2.61 to -0.02) (P for trend = 0.03). Loneliness components, personal feelings of isolation and the lack of relational connectedness but not the lack of collective connectedness, were also inversely associated with cognitive function. Significant indirect effects on cognitive function were observed for loneliness and its two components (personal feelings of isolation and the lack of relational connectedness) in mediating pathways via depressive symptoms, anxiety symptoms, and sleep disturbances (all p < 0.05). CONCLUSIONS: A higher degree of loneliness and its two components, personal feelings of isolation and the lack of relational connectedness, are associated with worse cognitive function among Chinese residents in nursing homes. Depressive symptoms, anxiety symptoms, and sleep disturbances may at least partially mediate these associations.
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Soledad , Trastornos del Sueño-Vigilia , Femenino , Humanos , Persona de Mediana Edad , Anciano , Masculino , Soledad/psicología , Depresión/diagnóstico , Depresión/epidemiología , Depresión/psicología , Pueblos del Este de Asia , Casas de Salud , Ansiedad/diagnóstico , Ansiedad/epidemiología , Trastornos del Sueño-Vigilia/diagnóstico , Trastornos del Sueño-Vigilia/epidemiología , Cognición , SueñoRESUMEN
BACKGROUND: Little is known about family members' and patients' expression of negative emotions among high-risk preoperative conversations. OBJECTIVES: This study aimed to identify the occurrence and patterns of the negative emotions of family members and patients in preoperative conversations, to investigate the conversation themes and to explore the correlation between the negative emotions and the conversation themes. METHODS: A retrospective study was conducted using the Chinese version of Verona Coding Definitions of Emotional Sequences (VR-CoDES-C) to code 297 conversations on high-risk procedures. Inductive content analysis was used to analyse the topics in which negative emotions nested. The χ2 Test was used to test the association between the cues and the conversation themes. RESULTS: The occurrence rate of family members' and patients' negative emotions was very high (85.9%), much higher when compared to most conversations under other medical settings. The negative emotions were mainly expressed by cues (96.4%), and cue-b (67.4%) was the most frequent category. Cues and concerns were mostly elicited by family members and patients (71.6%). Negative emotions were observed among seven themes, in which 'Psychological stress relating to illness severity, family's care and financial burden' (30.3%) ranked the top. Cue-b, cue-c and cue-d had a significant correlation (p < .001) with certain themes. CONCLUSIONS: Family members and patients conveyed significantly more negative emotions in the high-risk preoperative conversations than in other medical communications. Certain categories of cues were induced by specific emotional conversation contents. PATIENT CONTRIBUTION: Family members and patients contributed to data.
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Codificación Clínica , Comunicación , Familia , Pacientes , Relaciones Médico-Paciente , Procedimientos Quirúrgicos Operativos , China , Emociones , Familia/psicología , Humanos , Pacientes/psicología , Derivación y Consulta , Estudios Retrospectivos , Riesgo , Procedimientos Quirúrgicos Operativos/psicología , Encuestas y CuestionariosRESUMEN
In order to discover a broad-specificity and high stability chitinase, a marine fungus, Aspergillus fumigatus df347, was identified in the sediments of mangrove wetlands in Qinzhou Bay, China. The chitinase gene (AfChi28) from A. fumigatus df347 was cloned and heterologously expressed in Escherichia coli, and the recombinant enzyme AfChi28 was purified and characterized. AfChi28 is an acido-halotolerant- and temperature-resistant bifunctional enzyme with both endo- and exo-cleavage functions. Its enzymatic products are mainly GlcNAc, (GlcNAc)2, (GlcNAc)3 and (GlcNAc)4. Na+, Mg2+, K+, Ca2+ and Tris at a concentration of 50 mM had a strong stimulatory effect on AfChi28. The crude enzyme and pure enzyme exhibited the highest specific activity of 0.737 mU/mg and 52.414 mU/mg towards colloidal chitin. The DxDxE motif at the end of strand ß5 and with Glu154 as the catalytic residue was verified by the AlphaFold2 prediction and sequence alignment of homologous proteins. Moreover, the results of molecular docking showed that molecular modeling of chitohexaose was shown to bind to AfChi28 in subsites -4 to +2 in the deep groove substrate-binding pocket. This study demonstrates that AfChi28 is a promising chitinase for the preparation of desirable chitin oligosaccharides, and provides a foundation for elucidating the catalytic mechanism of chitinases from marine fungi.
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Quitinasas , Aspergillus fumigatus/genética , Quitina/química , Quitinasas/metabolismo , Escherichia coli/metabolismo , Hongos/metabolismo , Hidrólisis , Simulación del Acoplamiento Molecular , Especificidad por SustratoRESUMEN
Caring for people with dementia causes heavy care burdens to their families. Family coping is important in decreasing burdens and promoting family adaptation. To comprehensively assess and understand these issues, we validated the Chinese version of the Family Crisis Oriented Personal Evaluation Scales (F-COPES) which is widely used to evaluate family coping. Data for psychometric property evaluation were obtained from 215 family members of patients with dementia. The instrument showed satisfactory content validity (scale content validity index 0.98), convergent validity (r = 0.50, P < 0.01), and internal consistency (Cronbach's alpha 0.86). The confirmatory factor analysis identified six factors, namely, acquiring relatives' support, acquiring friends' support, acquiring neighbors' or others' support, seeking spiritual support, reframing, and passive appraisal (χ2/df 1.86, CFI 0.88, TLI 0.87, PGFI 0.68, RMSEA 0.06). This instrument may serve as a useful scale for assessing the coping behaviors of families of patients with dementia in mainland China.
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Adaptación Psicológica , Demencia , China , Humanos , Psicometría , Reproducibilidad de los Resultados , Espiritualidad , Encuestas y CuestionariosRESUMEN
Sepsis-induced acute kidney injury (AKI) continues to be associated with poor outcomes in critical care patients. Previous research has revealed that tetrahydrocurcumin (THC) exerts renoprotective effects in multiple nephritic disorders by modulating inflammation and oxidative stress. However, the effects of THC on sepsis-induced AKI and the underlying mechanisms remain unclear. In this study, a mouse model of sepsis-induced AKI, generated by cecal ligation and puncture operation, was used to investigate the protective effects of THC and the role of SIRT1. Histological manifestation and TUNEL analysis were observed to determine the severity of kidney damage. Levels of BUN, SCr, KIM-1, and UAlb/Cr were calculated to assess the renal function. Expressions of IL-1ß, IL-6, and TNF-α were measured to evaluate the inflammatory response. MDA content, SOD, GSH, CAT, and GPx activities and DHE staining were analyzed to estimate the degree of oxidative stress. Protein expressions of SIRT1, Ac-p65, and Ac-foxo1 were detected to explore the underlying mechanisms. We observed that THC not only increased the survival rate, improved the kidney function and ameliorated the renal histological damage of septic mice, but also inhibited inflammatory response, prohibited oxidative stress, and prevented cell apoptosis in renal tissues in septic mice. Mechanistically, THC remarkably increased the expression of SIRT1, accompanied by decreased expressions of downstream molecules Ac-p65 and Ac-foxo1. Meanwhile, the beneficial effects of THC were clearly abolished by the SIRT1-specific inhibitor EX527. These results delineate that THC prevents sepsis-induced AKI by suppressing inflammation and oxidative stress through activating the SIRT1 signaling.Abbreviation: Ac-p65: acetylated p65; Ac-foxo 1: acetylated forkhead box O1; AKI: acute kidney injury; BUN: blood urea nitrogen; CAT: catalase; DHE: dihydroethidium; GPx: glutathione peroxidase; GSH: reduced glutathione; IL-1ß: Interleukin-1 beta; IL-6: Interleukin-6; KIM-1: kidney injury molecule 1; MDA: malondialdehyde; SCr: serum creatinine; SIRT1: silent information regulator 1; SOD: superoxide dismutase; THC: tetrahydrocurcumin; TNF-α: tumor necrosis factor-alpha; TUNEL: TdT-mediated dUTP Nick-End Labeling; UAlb/Cr: urine micro albumin/creatinine.
Asunto(s)
Lesión Renal Aguda/prevención & control , Curcumina/análogos & derivados , Sustancias Protectoras/farmacología , Sepsis/metabolismo , Sirtuina 1/metabolismo , Lesión Renal Aguda/patología , Animales , Apoptosis/efectos de los fármacos , Nitrógeno de la Urea Sanguínea , Curcumina/farmacología , Citocinas/metabolismo , Inflamación/metabolismo , Riñón/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Estrés Oxidativo/efectos de los fármacos , Sepsis/patología , Transducción de Señal/efectos de los fármacosRESUMEN
For facing of the problems caused by the YOLOv4 algorithm's insensitivity to small objects and low detection precision in traffic light detection and recognition, the Improved YOLOv4 algorithm is investigated in the paper using the shallow feature enhancement mechanism and the bounding box uncertainty prediction mechanism. The shallow feature enhancement mechanism is used to extract features from the network and improve the network's ability to locate small objects and color resolution by merging two shallow features at different stages with the high-level semantic features obtained after two rounds of upsampling. Uncertainty is introduced in the bounding box prediction mechanism to improve the reliability of the prediction of the bounding box by modeling the output coordinates of the prediction bounding box and adding the Gaussian model to calculate the uncertainty of the coordinate information. The LISA traffic light data set is used to perform detection and recognition experiments separately. The Improved YOLOv4 algorithm is shown to have a high effectiveness in enhancing the detection and recognition precision of traffic lights. In the detection experiment, the area under the PR curve value of the Improved YOLOv4 algorithm is found to be 97.58%, which represents an increase of 7.09% in comparison to the 90.49% score gained in the Vision for Intelligent Vehicles and Applications Challenge Competition. In the recognition experiment, the mean average precision of the Improved YOLOv4 algorithm is 82.15%, which is 2.86% higher than that of the original YOLOv4 algorithm. The Improved YOLOv4 algorithm shows remarkable advantages as a robust and practical method for use in the real-time detection and recognition of traffic signal lights.