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Purpose: Although pediatric epidural analgesia is a well-established technique used perioperatively. It is unclear whether a lumbar or caudal epidural is suitable for osteogenesis imperfecta (OI) patients, which may be associated with brittle bones and spine deformity. We conducted a retrospective study to investigate and compare the efficacy of the two continuous epidural techniques in pediatric patients undergoing lower extremity osteotomy surgery using a propensity score-matched analysis (PSMA). Patients and Methods: A total of 274 patients were included. Patients' age, weight, and height were adjusted using PSMA. 90 patients were matched for further analysis, with 45 patients in the lumbar epidural group (Group L) and 45 patients in the caudal epidural group (Group C). Pain scores were categorized into three grades: mild (0-3), moderate (4-6), and severe (7-10), and compared between the two groups. Additionally, operation time, operation site, blood loss, scoliosis, oral analgesic medications, and catheter or nerve-related complications were compared. Results: There were no significant differences in operation time, operation site, scoliosis, and blood loss between the two groups. The percentage of moderate to severe pain during movement was significantly higher in Group L than in Group C, with 37.5% versus 17.5% on the second-day post-operation (P=0.039). However, no statistically significant difference was observed on other days. Additionally, there was no significant difference in oral medication consumption and complications between the two groups. Conclusion: Both lumbar and caudal epidural analgesia can be effectively used postoperatively, and a caudal epidural should be considered where performing a lumbar epidural is challenging in OI pediatric patients.
Osteogenesis imperfecta (OI) is a rare genetic disorder that affects the body's connective tissues, particularly the bones and ligaments. It is caused by abnormalities in type I collagen, which leads to skeletal fragility known as "brittle bones". This fragility can cause various issues, including an increased risk of fractures from minor trauma, limb deformities, and unusual fractures such as vertebral compressions. OI patients may also experience spinal manifestations such as scoliosis and kyphosis. Lumbar epidural analgesia has been found to be effective in providing pain relief for surgeries that involve the lower extremities. Additionally, caudal epidural analgesia has also demonstrated its effectiveness in providing postoperative analgesia for surgeries that affect the lower limbs. However, there is still debate about the safety of epidural analgesia in patients with skeletal dysplasias, especially those with OI. Despite this uncertainty, our center, which was supported by the Rare Diseases Public Welfare Organization, has successfully used epidural analgesia since 2015 in the southern part of China for OI surgeries. We conducted a retrospective study to share our experiences of nine years of practice and compare lumbar epidural with caudal epidural using a propensity score matching to balance basic demographics. We also compared the presence of scoliosis. Our findings suggest that both lumbar and caudal epidural analgesia can be safely used in OI patients. In cases where lumbar punctures may pose challenges due to potential spine deformities, the caudal route can be an alternative.
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Conflicts in urban subsystems have severely hindered the realization of sustainable development, among which the most serious is the conflict between the environmental subsystem and urban development. Differing from studies considering individual environmental elements, this paper innovatively investigates the quantitative relationship between overall environmental performance and other development dimensions to understand the quantitative role of the environmental subsystem in sustainable urban development. Taking the nine megacities in China as an example, this paper first develops the performance variables of four urban subsystems, including the environment, by entropy method and analyzes the conflict or coordination level between the environment and other subsystems through the coupling coordination degree model (CCDM). Then, the interaction mechanism is further analyzed by the fully modified ordinary least square (FMOLS) and vector error correction model (VECM). This paper tries to provide a new reference for management and decision-making by focusing on the whole environmental subsystem rather than separate elements, which is of theoretical and practical significance. The main conclusions are as follows: (1) The coordination level between the environment and other urban subsystems is low; (2) 1 % rise in the economic and resource performance can respectively lead to 0.2014 % and 0.1388 % declines in the environmental performance; (3) 1 % increase in social performance can bring a 0.3738 % rise in environmental performance; (4) Improving environmental and resource subsystems' performance is the priority; (5) Coordinating urban subsystems is the key to long-run sustainable development. Despite the case studies on megacities in China, we hope to provide a new reference for cities worldwide with concentrated populations, rapid growth, and complex development contradictions.
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Pyrethroid insecticides are among urban parks' most widely used and harmful insecticides. The advanced prediction method is the key to studying the pollution and diffusion risk of plant conservation insecticides in parks. A two-dimensional advection-dispersion model was established for the North Lake of Cloud Mountain Park in the subhumid area of Hebei Province. The temporal and spatial distribution of lambda-cyhalothrin pollution required by plant growth in artificial lakes under different rainfall intensities and the time of water renewal after rainfall was simulated and predicted. According to the model efficiency (E: 0.98), mean absolute error (MAE: 0.016-0.064 cm), and root mean square error (RMSE: 0.014-0.041 cm), the prediction results showed that the model fits well. The results showed that the concentration of lambda-cyhalothrin in the artificial lake was positively correlated with the increase in rainfall intensity. Under the three scenarios of moderate rain, heavy rain, and rainstorm, the variation of total pollutants into the lake over time conformed to the first-order dynamic equation (R2ï¼0.97), and the cumulative rates were 0.013 min-1, 0.019 min-1 and 0.022 min-1, respectively. Under light rain, the accumulation rate of lambda-cyhalothrin showed a double-linear relationship, which was in accordance with the second-order kinetic equation (R2ï¼0.97). The rapid accumulation rate of early-stage rainfall was 0.0024 min-1, and the slow accumulation rate of late-stage rainfall was 0.0019 min-1. The human health risk assessment predicted by the simulation was lower than the hazard value (Rtgn(a-1): 9.65 E-11-1.12 E-10 a-1). However, the potential risk value to aquatic species was higher (RQ: 0.33-23.05). In addition, the increase in rainfall intensity has no significant effect on the acceleration of water renewal time. The two-dimensional dispersion model of pollutants driven by water dynamics provided relevant examples for evaluating the impact of runoff on pesticide scour in parks and supplied scientific support for improving the management of artificial lakes in urban parks.
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Contaminantes Ambientales , Insecticidas , Piretrinas , Contaminantes Químicos del Agua , Humanos , Insecticidas/análisis , Lagos , Monitoreo del Ambiente/métodos , Agua , Lluvia , China , Movimientos del Agua , Contaminantes Químicos del Agua/análisisRESUMEN
Rapid urbanization has triggered more serious urban flood risks. Many studies have focused on intra-urban flooding, but less attention has been paid to rainfall and flood risks at the urban fringe. Nowadays, China is vigorously promoting the construction of sponge cities in the whole area. It is important to study the construction of sponge cities in shallow mountainous areas, which are an important barrier between cities and mountains. The purpose of this paper is to investigate the performance of Low-Impact Development (LID) facilities under different rainfall scenarios in developed shallow mountainous areas. The second garden and flower exposition ("the Expo Park") in Hebei Province is used as an example. The SWMM and MIKE21 models were used to simulate the hydrological processes before and after the construction of "the Expo Park", and the models were calibrated with the measured data. Peak flow rate, outflow volume, rainfall-outflow ratio, runoff velocity, and water feature area of the water system were used as indicators to evaluate their effectiveness. The results showed that the placement of LID facilities had a positive impact on the construction of the shallow mountain area. Specifically, (1) LID facilities can reduce the peak flow rate, delayed peak flow time, outflow volume, and rainfall outflow ratio of stormwater runoff in mountainous areas; and (2) they can effectively collect rainwater and become a supplement to the landscape water system of the site. These findings provide a scientific basis for the construction of LID facilities in shallow mountainous areas, which is important for the development and flood management of shallow mountainous areas.
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Lluvia , Movimientos del Agua , Agua , Hidrología , Ciudades , ChinaRESUMEN
[This corrects the article DOI: 10.3389/fimmu.2020.585168.].
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BACKGROUND: Rheumatoid arthritis (RA) is an inflammatory disease that manifests as a preclinical stage of systemic autoimmunity followed by chronic progressive synovitis. Disease-associated genetic SNP variants predominantly map to non-coding, regulatory regions of functional importance in CD4 T cells, implicating these cells as key regulators. A better understanding of the epigenome of CD4 T cells holds the promise of providing information on the interaction between genetic susceptibility and exogenous factors. METHODS: We mapped regions of chromatin accessibility using ATAC-seq in peripheral CD4 T cell subsets of patients with RA (n=18) and compared them to T cells from patients with psoriatic arthritis (n=11) and age-matched healthy controls (n=10). Transcripts of selected genes were quantified using qPCR. FINDINGS: RA-associated epigenetic signatures were identified that in part overlapped between central and effector memory CD4 T cells and that were to a lesser extent already present in naïve cells. Sites more accessible in RA were highly enriched for the motif of the transcription factor (TF) CTCF suggesting differences in the three-dimensional chromatin structure. Unexpectedly, sites with reduced chromatin accessibility were enriched for motifs of TFs pertinent for T cell function. Most strikingly, super-enhancers encompassing RA-associated SNPs were less accessible. Analysis of selected transcripts and published DNA methylation patterns were consistent with this finding. The preferential loss in accessibility at these super-enhancers was seen in patients with high and low disease activity and on a variety of immunosuppressive treatment modalities. INTERPRETATION: Disease-associated genes are epigenetically less poised to respond in CD4 T cells from patients with established RA. FUNDING: This work was supported by I01 BX001669 from the Veterans Administration.
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Artritis Reumatoide , Linfocitos T CD4-Positivos , Artritis Reumatoide/genética , Cromatina/genética , Metilación de ADN , Humanos , Secuencias Reguladoras de Ácidos NucleicosRESUMEN
The Spt/Ada-Gcn5 Acetyltransferase (SAGA) coactivator complex has multiple modules with different enzymatic and non-enzymatic functions. How each module contributes to gene expression is not well understood. During Drosophila oogenesis, the enzymatic functions are not equally required, which may indicate that different genes require different enzymatic functions. An analogy for this phenomenon is the handyman principle: while a handyman has many tools, which tool he uses depends on what requires maintenance. Here we analyzed the role of the non-enzymatic core module during Drosophila oogenesis, which interacts with TBP. We show that depletion of SAGA-specific core subunits blocked egg chamber development at earlier stages than depletion of enzymatic subunits. These results, as well as additional genetic analyses, point to an interaction with TBP and suggest a differential role of SAGA modules at different promoter types. However, SAGA subunits co-occupied all promoter types of active genes in ChIP-seq and ChIP-nexus experiments, and the complex was not specifically associated with distinct promoter types in the ovary. The high-resolution genomic binding profiles were congruent with SAGA recruitment by activators upstream of the start site, and retention on chromatin by interactions with modified histones downstream of the start site. Our data illustrate that a distinct genetic requirement for specific components may conceal the fact that the entire complex is physically present and suggests that the biological context defines which module functions are critical.
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Proteínas de Drosophila/metabolismo , Drosophila melanogaster/fisiología , Histona Acetiltransferasas/metabolismo , Oogénesis/fisiología , Regiones Promotoras Genéticas , Animales , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Histona Acetiltransferasas/genética , Oogénesis/genéticaRESUMEN
The nutrient-sensing mammalian target of rapamycin (mTOR) is integral to cell fate decisions after T cell activation. Sustained mTORC1 activity favors the generation of terminally differentiated effector T cells instead of follicular helper and memory T cells. This is particularly pertinent for T cell responses of older adults who have sustained mTORC1 activation despite dysfunctional lysosomes. Here, we show that lysosome-deficient T cells rely on late endosomes rather than lysosomes as an mTORC1 activation platform, where mTORC1 is activated by sensing cytosolic amino acids. T cells from older adults have an increased expression of the plasma membrane leucine transporter SLC7A5 to provide a cytosolic amino acid source. Hence, SLC7A5 and VPS39 deficiency (a member of the HOPS complex promoting early to late endosome conversion) substantially reduced mTORC1 activities in T cells from older but not young individuals. Late endosomal mTORC1 is independent of the negative-feedback loop involving mTORC1-induced inactivation of the transcription factor TFEB that controls expression of lysosomal genes. The resulting sustained mTORC1 activation impaired lysosome function and prevented lysosomal degradation of PD-1 in CD4+ T cells from older adults, thereby inhibiting their proliferative responses. VPS39 silencing of human T cells improved their expansion to pertussis and to SARS-CoV-2 peptides in vitro. Furthermore, adoptive transfer of CD4+ Vps39-deficient LCMV-specific SMARTA cells improved germinal center responses, CD8+ memory T cell generation, and recall responses to infection. Thus, curtailing late endosomal mTORC1 activity is a promising strategy to enhance T cell immunity.
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Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , COVID-19/inmunología , Endosomas/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , SARS-CoV-2/metabolismo , Transducción de Señal/genética , Traslado Adoptivo/métodos , Adulto , Anciano , Anciano de 80 o más Años , Animales , Proteínas Relacionadas con la Autofagia/deficiencia , Proteínas Relacionadas con la Autofagia/genética , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , COVID-19/virología , Células Cultivadas , Femenino , Proteína Forkhead Box O1/deficiencia , Proteína Forkhead Box O1/genética , Voluntarios Sanos , Humanos , Transportador de Aminoácidos Neutros Grandes 1/metabolismo , Lisosomas/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Transducción de Señal/inmunología , Transfección , Proteínas de Transporte Vesicular/deficiencia , Proteínas de Transporte Vesicular/genética , Adulto JovenRESUMEN
Healthy immune aging is in part determined by how well the sizes of naïve T cell compartments are being maintained with advancing age. Throughout adult life, replenishment largely derives from homeostatic proliferation of existing naïve and memory T cell populations. However, while the subpopulation composition of CD4 T cells is relatively stable, the CD8 T cell compartment undergoes more drastic changes with loss of naïve CD8 T cells and accumulation of effector T cells, suggesting that CD4 T cells are more resilient to resist age-associated changes. To determine the epigenetic basis for these differences in behaviors, we compared chromatin accessibility maps of CD4 and CD8 T cell subsets from young and old individuals and related the results to the expressed transcriptome. The dominant age-associated signatures resembled hallmarks of differentiation, which were more pronounced for CD8 naïve and memory than the corresponding CD4 T cell subsets, indicating that CD8 T cells are less able to keep cellular quiescence upon homeostatic proliferation. In parallel, CD8 T cells from old adults, irrespective of their differentiation state, displayed greater reduced accessibility to genes of basic cell biological function, including genes encoding ribosomal proteins. One possible mechanism is the reduced expression of the transcription factors YY1 and NRF1. Our data suggest that chromatin accessibility signatures can be identified that distinguish CD4 and CD8 T cells from old adults and that may confer the higher resilience of CD4 T cells to aging.
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Envejecimiento/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Inmunosenescencia/inmunología , Adulto , Anciano , Envejecimiento/genética , Epigénesis Genética/genética , Epigénesis Genética/inmunología , Femenino , Humanos , Memoria Inmunológica/genética , Memoria Inmunológica/inmunología , Inmunosenescencia/genética , Masculino , Transcriptoma/genética , Transcriptoma/inmunologíaRESUMEN
T cell differentiation involves the dynamic regulation of FOXO1 expression, which rapidly declines after activation and is subsequently restored. Reexpression is impaired in naïve CD4+ T cell responses from older individuals. Here, we show that FOXO1 promotes lysosome function through the induction of the key transcription factor for lysosomal proteins, TFEB. Subdued FOXO1 reexpression in activated CD4+ T cells impairs lysosomal activity, causing an expansion of multivesicular bodies (MVBs). Expansion of the MVB compartment induces the sequestration of glycogen synthase kinase 3ß (GSK3ß), thereby suppressing protein turnover and enhancing glycolytic activity. As a consequence, older activated CD4+ T cells develop features reminiscent of senescent cells. They acquire an increased cell mass, preferentially differentiate into short-lived effector T cells, and secrete exosomes that harm cells in the local environment through the release of granzyme B.
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A signal multi-amplified electrochemical biosensor was fabricated for tau-441 protein, a dementia biomarker. It utilizes a carbon nanocomposite film modified gold electrode. The carbon nanocomposite film was composed of multi-walled carbon nanotubes (MWCNTs), reduced graphene oxide (rGO), and chitosan (CS). For the nanocomposite film, rGO improved the dispersibility of MWCNTs, and the effective surface area of MWCNTs was increased. On the other hand, MWCNTs also increased the interlayer spacing of rGO, resulting in a thinner rGO layer. MWCNTs-rGO had a better conductivity than that of MWCNTs and rGO due to the synergy effect. Biocompatible CS was employed for immobilization of the specific antibody. Tau-441 protein was modified with gold nanoparticles (AuNPs) for signal amplification again. The response of the electrochemical biosensor is linear in the range 0.5-80 fM (0.5, 1.5, 5, 10, 40, 80 fM) with a limit of detection (LOD) of 0.46 fM, using differential pulse voltammetry (DPV) in a potential range of - 100-500 mV. The biosensor was successfully applied to the analysis of serum samples of 14 normal people, 14 mild cognitive impairment (MCI) patients, and 14 dementia patients. Graphical abstract Schematic representation of signal multi-amplified electrochemical biosensor for determination of tau-441 protein in human serum.
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Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Nanopartículas del Metal/química , Nanotubos de Carbono/química , Proteínas tau/sangre , Anticuerpos Inmovilizados/inmunología , Quitosano/química , Oro/química , Grafito/química , Humanos , Inmunoensayo/métodos , Límite de Detección , Nanocompuestos/química , Isoformas de Proteínas/sangre , Isoformas de Proteínas/inmunología , Proteínas tau/inmunologíaRESUMEN
Vaccination is a mainstay in preventive medicine, reducing morbidity and mortality from infection, largely by generating pathogen-specific neutralizing antibodies. However, standard immunization strategies are insufficient with increasing age due to immunological impediments, including defects in T follicular helper (Tfh) cells. Here, we found that Tfh generation is inversely linked to the expression of the ecto-NTPDase CD39 that modifies purinergic signaling. The lineage-determining transcription factor BCL6 inhibited CD39 expression, while increased Tfh frequencies were found in individuals with a germline polymorphism preventing transcription of ENTPD1, encoding CD39. In in vitro human and in vivo mouse studies, Tfh generation and germinal center responses were enhanced by reducing CD39 expression through the inhibition of the cAMP/PKA/p-CREB pathway, or by blocking adenosine signaling downstream of CD39 using the selective adenosine A2a receptor antagonist istradefylline. Thus, purinergic signaling in differentiating T cells can be targeted to improve vaccine responses, in particular in older individuals who have increased CD39 expression.
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Apirasa/inmunología , Diferenciación Celular/inmunología , Regulación Enzimológica de la Expresión Génica/inmunología , Centro Germinal/inmunología , Transducción de Señal/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Apirasa/genética , Centro Germinal/citología , Humanos , Ratones , Ratones Transgénicos , Linfocitos T Colaboradores-Inductores/citologíaRESUMEN
An efficient green method of gold nanoparticles (AuNPs) biosynthesis was achieved by cell-free extracts of fungus Trichoderma sp. WL-Go. Based on UV-Vis spectra, AuNPs biosynthesised by cell-free extracts with 90â mg/l protein exhibited a characteristic absorption band at 556â nm and was stable for 7 days. Transmission electron microscopy images revealed that the as-synthesised AuNPs were spherical and pseudo-spherical, and the average size was calculated to be 9.8â nm with a size range of 1-24â nm. The AuNPs illustrated their good catalytic activities for reduction of nitro-aromatics (2-nitrophenol, 3-nitrophenol, 4-nitrophenol, 2-nitroaniline, 3-nitroaniline) with catalytic rate constants of 7.4 × 10-3â s-1, 10.3 × 10-3â s-1, 4.9 × 10-3â s-1, 5.8 × 10-3â s-1, 15.0 × 10-3â s-1, respectively. Meanwhile, the AuNPs also showed excellent catalytic performance in decolourisation of azo dyes with decolourisation efficiency from 82.2 to 97.5%. This study provided a green gentle method for AuNPs synthesis as well as exhibiting efficient catalytic capability for degradation of aromatic pollutants.
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Oro/química , Nanopartículas del Metal/química , Nitrofenoles/química , Trichoderma , Contaminantes del Agua/química , Tecnología Química Verde , Nitrofenoles/aislamiento & purificación , Nitrofenoles/metabolismo , Tamaño de la Partícula , Trichoderma/química , Trichoderma/metabolismo , Contaminantes del Agua/aislamiento & purificación , Contaminantes del Agua/metabolismoRESUMEN
The Gcn5 acetyltransferase functions in multiple acetyltransferase complexes in yeast and metazoans. Yeast Gcn5 is part of the large SAGA (Spt-Ada-Gcn5 acetyltransferase) complex and a smaller ADA acetyltransferase complex. In flies and mammals, Gcn5 (and its homolog pCAF) is part of various versions of the SAGA complex and another large acetyltransferase complex, ATAC (Ada2A containing acetyltransferase complex). However, a complex analogous to the small ADA complex in yeast has never been described in metazoans. Previous studies in Drosophila hinted at the existence of a small complex which contains Ada2b, a partner of Gcn5 in the SAGA complex. Here we have purified and characterized the composition of this complex and show that it is composed of Gcn5, Ada2b, Ada3 and Sgf29. Hence, we have named it the metazoan 'ADA complex'. We demonstrate that the fly ADA complex has histone acetylation activity on histones and nucleosome substrates. Moreover, ChIP-Sequencing experiments identified Ada2b peaks that overlap with another SAGA subunit, Spt3, as well as Ada2b peaks that do not overlap with Spt3 suggesting that the ADA complex binds chromosomal sites independent of the larger SAGA complex.
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Proteínas de Drosophila/metabolismo , Drosophila melanogaster/enzimología , Histona Acetiltransferasas/metabolismo , Complejos Multienzimáticos/química , Complejos Multienzimáticos/metabolismo , Proteínas Nucleares/metabolismo , Animales , Línea Celular , Cromatina/metabolismo , Proteínas de Drosophila/aislamiento & purificación , Drosophila melanogaster/citología , Histona Acetiltransferasas/aislamiento & purificación , Complejos Multienzimáticos/aislamiento & purificación , Proteínas Nucleares/aislamiento & purificación , Transactivadores/aislamiento & purificación , Transactivadores/metabolismoRESUMEN
Circulating tumor DNA (ctDNA) as a class of liquid biopsy is a type of gene fragment that contains tumor-specific gene changes in body fluids such as human peripheral blood. More and more evidences show that ctDNA is an excellent tumor biomarker for diagnosis, prognosis, tumor heterogeneity and so on. ctDNA is a tumor code in the blood. Liquid biopsy of ctDNA is firstly summarized. Compared with the traditional detection technologies of ctDNA, the biosensor is an excellent choice for the detection of ctDNA because of its portability, sensitivity, specificity and ease of use. This review mainly evaluates various biosensors applied to the detection of ctDNA. We discuss the most commonly used bioreceptors to specifically identify and bind ctDNA, including complementary DNA (cDNA), peptide nucleic acid (PNA) and anti-5 MethylCytosines, and the biotransducers which convert biological signals to analysable signs. The review also discusses signal amplification strategies in biosensors to detect ctDNA.
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Biomarcadores de Tumor/sangre , Técnicas Biosensibles , ADN Tumoral Circulante/aislamiento & purificación , ADN Tumoral Circulante/sangre , ADN Complementario/química , ADN Complementario/genética , Humanos , Biopsia Líquida , Células Neoplásicas Circulantes/patologíaRESUMEN
Graphene oxide (GO) is a new type of nanomaterial with unique physicochemical properties and diverse applications, whereas it poses potential risk to human and environment. By screening from natural soil exposed to GO in the laboratory, we successfully obtained a novel bacterium, Labrys sp. WJW, which was able to use GO as the sole carbon source for growth. Within 8 days, cell numbers increased 16.76⯱â¯3.21 folds using 100â¯mg/L GO as the carbon source by qPCR analysis. The bacterial biodegradation which resulted in formation of holes and functional group changes of GO was proved by Raman spectroscopy, atomic force microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy analyses. Aromatic intermediates with structures of benzoic acid and phenol were identified using gas chromatograph-mass spectrometry and liquid chromatography/time-of-flight/mass spectrometry. Combination of genomic and proteomic analyses were performed to explore the proteins associated with GO degradation. A total of 644 proteins were significantly shifted. Bioinformatics analysis indicated that part of the up-regulated proteins were related to oxidation, ring cleavage and intermediates transmembrane processes, and GO was supposed to be degraded to benzoate and further degraded for downstream processes. This study enriches our understanding and provides new insights into the environmental fate of GO.
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Alphaproteobacteria/metabolismo , Grafito/metabolismo , Nanoestructuras , Alphaproteobacteria/genética , Alphaproteobacteria/crecimiento & desarrollo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biodegradación Ambiental , Carbono/metabolismo , Grafito/química , Humanos , Microscopía de Fuerza Atómica , Microscopía Electrónica de Transmisión , Nanoestructuras/química , Oxidación-Reducción , Óxidos/química , Óxidos/metabolismo , Espectroscopía de Fotoelectrones , Proteómica , Microbiología del Suelo , Espectrometría RamanRESUMEN
Biosynthesis of gold nanoparticles (AuNPs) by microbes has received much attention as an efficient and eco-friendly process. However, the characteristics of AuNPs biosynthesized by different microbial cell-free extracts are rarely comparatively studied. In this study, three locally isolated strains, i.e., bacteria Labrys sp. WJW, yeast Trichosporon montevideense WIN, and filamentous fungus Aspergillus sp. WL-Au, were selected for AuNPs biosynthesis. UV-Vis absorption bands at 538, 539, and 543 nm confirmed the formation of AuNPs by these strains. Transmission electron microscopy and selected area electron diffraction analyses revealed that the as-synthesized AuNPs were crystalline with spherical or pseudo-spherical shapes. However, the average sizes of these AuNPs were diverse, which were 18.8, 22.2 and 9.5 nm, respectively. The biomolecules involved in nanoparticles stabilization were demonstrated by Fourier transform infrared spectroscopy analysis. Four common functional groups such as -N-H, -C=C, -N=O, and -S=O groups were detected in these AuNPs, while a distinct -C=O group was involved in WL-Au-AuNPs. The catalytic rate of WL-Au-AuNPs toward 4-nitrophenol reduction (0.37 min-1) was much higher than those of others (WJW-AuNPs 0.27 min-1 and WIN-AuNPs 0.23 min-1). This research would provide useful information for exploring efficient microbial candidates to synthesize AuNPs with excellent performances.
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Aspergillus/química , Oro/química , Nanopartículas del Metal/química , Nitrofenoles/química , Trichosporon/química , Microscopía Electrónica de Transmisión , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
In this paper, without transforming the second order inertial neural networks into the first order differential systems by some variable substitutions, asymptotic stability and synchronization for a class of delayed inertial neural networks are investigated. Firstly, a new Lyapunov functional is constructed to directly propose the asymptotic stability of the inertial neural networks, and some new stability criteria are derived by means of Barbalat Lemma. Additionally, by designing a new feedback control strategy, the asymptotic synchronization of the addressed inertial networks is studied and some effective conditions are obtained. To reduce the control cost, an adaptive control scheme is designed to realize the asymptotic synchronization. It is noted that the dynamical behaviors of inertial neural networks are directly analyzed in this paper by constructing some new Lyapunov functionals, this is totally different from the traditional reduced-order variable substitution method. Finally, some numerical simulations are given to demonstrate the effectiveness of the derived theoretical results.
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Retroalimentación , Redes Neurales de la Computación , Algoritmos , Factores de TiempoRESUMEN
The Spt-Ada-Gcn5-acetyltransferase (SAGA) chromatin-modifying complex is a transcriptional coactivator that contains four different modules of subunits. The intact SAGA complex has been well characterized for its function in transcription regulation and development. However, little is known about the roles of individual modules within SAGA and whether they have any SAGA-independent functions. Here we demonstrate that the two enzymatic modules of Drosophila SAGA are differently required in oogenesis. Loss of the histone acetyltransferase (HAT) activity blocks oogenesis, while loss of the H2B deubiquitinase (DUB) activity does not. However, the DUB module regulates a subset of genes in early embryogenesis, and loss of the DUB subunits causes defects in embryogenesis. ChIP-seq (chromatin immunoprecipitation [ChIP] combined with high-throughput sequencing) analysis revealed that both the DUB and HAT modules bind most SAGA target genes even though many of these targets do not require the DUB module for expression. Furthermore, we found that the DUB module can bind to chromatin and regulate transcription independently of the HAT module. Our results suggest that the DUB module has functions within SAGA and independent functions.
Asunto(s)
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crecimiento & desarrollo , Drosophila melanogaster/genética , Regulación del Desarrollo de la Expresión Génica , Histona Acetiltransferasas/metabolismo , Oogénesis/genética , Animales , Ataxina-7/genética , Cromatina/metabolismo , Enzimas Desubicuitinizantes/metabolismo , Proteínas de Drosophila/genética , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Histona Acetiltransferasas/genética , Histonas/metabolismo , Microscopía Confocal , Ovario/crecimiento & desarrollo , Unión Proteica , Cigoto/fisiologíaRESUMEN
In the present study, biosynthesis of gold nanoparticles (AuNPs) by the cells (cells-AuNPs) and cell-free extracts (extracts-AuNPs) of a new fungus Mariannaea sp. HJ was reported. The as-synthesized particles were characterized by UV-vis spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The effects of different parameters on AuNP biosynthesis were investigated, and initial gold ion concentration of 2 mM, pH 7, was demonstrated to be suitable for both cells-AuNP and extracts-AuNP syntheses. The cells-AuNPs were of various shapes, including sphere, hexagon, and irregular shapes, with an average size of 37.4 nm, while the extracts-AuNPs were almost spherical and pseudo-spherical with an average size of 11.7 nm. XRD pattern suggested that the crystal structure of both AuNPs was face-centered cubic. FTIR spectra implied that some biomolecules from the fungal cell walls or cell-free extracts were involved in the formation of AuNPs. The as-synthesized AuNPs were demonstrated to have excellent catalytic activities for the reduction of 4-nitrophenol with the catalytic rate constants of 5.7 × 10-3/s for cells-AuNPs and 24.7 × 10-3/s for extracts-AuNPs. To the best of our knowledge, this is the first report on AuNP biosynthesis by Mariannaea sp.