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1.
Mycologia ; : 1-12, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39208238

RESUMEN

The study of myxomycete biogeography has a long-standing history and has consistently drawn scholarly interest. Nevertheless, studies focusing specifically on the spatial and temporal distribution patterns of myxomycete diversity are relatively limited, with even fewer investigating the mechanisms driving the generation and maintenance of myxomycete diversity. Therefore, this study selected two geographically distant sampling sites within northern Chinese forests to investigate myxomycete species composition, community structure, environmental drivers, and assembly patterns under geographic barriers. We established plots in the Altai Mountains (ALE) and the Greater Khingan Mountains (GKM), gathered bark and litter, and conducted 80-day moist chamber cultures of myxomycetes. Additionally, myxomycete specimens were collected in the field simultaneously to supplement the data set. This study collected 541 myxomycete specimens belonging to 73 species from 28 genera, spanning 12 families and eight orders. The ALE and the GKM had 20 identical species, accounting for 27% of the total species. Myxomycetes from both regions exhibited abundant occurrence 18 days after cultivation, with the quantity on bark substrates notably higher than on litter. Arcyria pomiformis and Comatricha elegans were the most common species in moist chamber cultures. Mantel test outcomes revealed that environmental factors had no significant impact on myxomycete community similarity between the two areas, aligning with findings from the neutral community model analysis, indicating a predominant influence of stochastic processes on myxomycete community structure in moist chamber cultures. This study represents the first application of a quantitative framework to analyze myxomycete community assembly cultivated in moist chambers.

2.
Appl Environ Microbiol ; 90(9): e0135924, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39171904

RESUMEN

The Altai Mountains (ALE) and the Greater Khingan Mountains (GKM) in northern China are forest regions dominated by coniferous trees. These geographically isolated regions provide an ideal setting for studying microbial biogeographic patterns. In this study, we employed high-throughput techniques to obtain DNA sequences of soil myxomycetes, bacteria, and fungi and explored the mechanisms underlying the assembly of both local and cross-regional microbial communities in relation to environmental factors. Our investigation revealed that the environmental heterogeneity in ALE and GKM significantly affected the succession and assembly of soil bacterial communities at cross-regional scales. Specifically, the optimal environmental factors affecting bacterial Bray-Curtis similarity were elevation and temperature seasonality. The spatial factors and climate change impact on bacterial communities under the geographical barriers surpassed that of local soil microenvironments. The assembly pattern of bacterial communities transitions from local drift to cross-regional heterogeneous selection. Environmental factors had a relatively weak influence on myxomycetes and fungi. Both soil myxomycetes and fungi faced considerable dispersal limitation at local and cross-regional scales, ultimately leading to weak geographical distribution patterns.IMPORTANCEThe impact of environmental selection and dispersal on the soil microbial spatial distribution is a key concern in microbial biogeography, particularly in large-scale geographical patterns. However, our current understanding remains limited. Our study found that soil bacteria displayed a distinct cross-regional geographical distribution pattern, primarily influenced by environmental selection. Conversely, the cross-regional geographical distribution patterns of soil myxomycetes and fungi were relatively weak. Their composition exhibited a weak association with the environment at local and cross-regional scales, with assembly primarily driven by dispersal limitation.


Asunto(s)
Bacterias , Hongos , Microbiota , Microbiología del Suelo , China , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Hongos/genética , Hongos/clasificación , Hongos/aislamiento & purificación , Mixomicetos/genética , Mixomicetos/clasificación , Cambio Climático , Bosques
3.
Small ; : e2403099, 2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38973084

RESUMEN

Bottom-up patterning technology plays a significant role in both nature and synthetic materials, owing to its inherent advantages such as ease of implementation, spontaneity, and noncontact attributes, etc. However, constrained by the uncontrollability of molecular movement, energy interaction, and stress, obtained micropatterns tend to exhibit an inevitable arched outline, resulting in the limitation of applicability. Herein, inspired by auxin's action mode in apical dominance, a versatile strategy is proposed for fabricating precision self-organizing micropatterns with impressive height based on polymerization-induced acropetal migration. The copolymer containing fluorocarbon chains (low surface energy) and tertiary amine (coinitiator) is designed to self-assemble on the surface of the photo-curing system. The selective exposure under a photomask establishes a photocuring boundary and the radicals would be generated on the surface, which is pivotal in generating a vertical concentration difference of monomer. Subsequent heating treatment activates the material continuously transfers from the unexposed area to the exposed area and is accompanied by the obviously vertical upward mass transfer, resulting in the manufacture of a rectilinear profile micropattern. This strategy significantly broadens the applicability of self-organizing patterns, offering the potential to mitigate the complexity and time-consuming limitations associated with top-down methods.

4.
Arch Microbiol ; 206(8): 364, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080072

RESUMEN

Four species of myxomycetes (Arcyria pseudodenudata, Diderma europaeum, Lycogala irregulare, and Trichia armillata) new to China were observed via light microscope and scanning electron microscope, and detailed descriptions and illustrations are provided, along with comparisons with related species. Among them, A. pseudodenudata was discovered for the first time outside of the type locality, D. europaeum was discovered for the first time outside of Europe, and L. irregulare and T. armillata were reported again after being named. Phylogenetic analyses based on nuclear 18S rDNA and elongation factor-1 alpha sequences or nuclear 18S rDNA and cytochrome oxidase subunit I sequences was performed to provide a molecular basis for morphological identification. These specimens were deposited in the Herbarium of Fungi of Nanjing Normal University.


Asunto(s)
Mixomicetos , Filogenia , ARN Ribosómico 18S , China , Mixomicetos/clasificación , Mixomicetos/genética , Mixomicetos/aislamiento & purificación , Mixomicetos/ultraestructura , ARN Ribosómico 18S/genética , ADN Ribosómico/genética , Complejo IV de Transporte de Electrones/genética , Factor 1 de Elongación Peptídica/genética , Análisis de Secuencia de ADN
5.
Adv Mater ; 36(25): e2400849, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38567824

RESUMEN

Harnessing the spontaneous surface instability of pliable substances to create intricate, well-ordered, and on-demand controlled surface patterns holds great potential for advancing applications in optical, electrical, and biological processes. However, the current limitations stem from challenges in modulating multidirectional stress fields and diverse boundary environments. Herein, this work proposes a universal strategy to achieve arbitrarily controllable wrinkle patterns via the spatiotemporal photochemical boundaries. Utilizing constraints and inductive effects of the photochemical boundaries, the multiple coupling relationship is accomplished among the light fields, stress fields, and morphology of wrinkles in photosensitive polyurethane (PSPU) film. Moreover, employing sequential light-irradiation with photomask enables the attainment of a diverse array of controllable patterns, ranging from highly ordered 2D patterns to periodic or intricate designs. The fundamental mechanics of underlying buckling and the formation of surface features are comprehensively elucidated through theoretical stimulation and finite element analysis. The results reveal the evolution laws of wrinkles under photochemical boundaries and represent a new effective toolkit for fabricating intricate and captivating patterns in single-layer films.

6.
Adv Mater ; 36(19): e2312650, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38339884

RESUMEN

Optical grating devices based on micro/nanostructured functional surfaces are widely employed to precisely manipulate light propagation, which is significant for information technologies, optical data storage, and light sensors. However, the parameters of rigid periodic structures are difficult to tune after manufacturing, which seriously limits their capacity for in situ light manipulation. Here, a novel anti-eavesdropping, anti-damage, and anti-tamper dynamic optical encryption strategy are reported via tunable mechanical composite wrinkle micrograting encryption systems (MCWGES). By mechanically composing multiple in-situ tunable ordered wrinkle gratings, the dynamic keys with large space capacity are generated to obtain encrypted diffraction patterns, which can provide a higher level of security for the encrypted systems. Furthermore, a multiple grating cone diffraction model is proposed to reveal the dynamic optical encryption principle of MCWGES. Optical encryption communication using dynamic keys has the effect of preventing eavesdropping, damage, and tampering. This dynamic encryption method based on optical manipulation of wrinkle grating demonstrates the potential applications of micro/nanostructured functional surfaces in the field of information security.

7.
Adv Mater ; 36(9): e2307445, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37930053

RESUMEN

Elastomers with high aspect ratio surface patterns are a promising class of materials for designing soft machines in the future. Here, a facile method for fabricating surface patterns on polyurethane elastomer by subtly utilizing the Poisson effect and gradient photocrosslinking is demonstrated. By applying uniaxial tensile strains, the aspect ratio of the surface patterns can be optionally manipulated. At prestretched state, the pattern on the polyurethane elastomer can be readily constructed through compressive stress, resulting from the gradient photocrosslinking via selective photodimerization of an anthracene-functionalized polyurethane elastomer (referred to as ANPU). The macromolecular aggregation structures during stretching deformation significantly contribute to the fabrication of high aspect ratio surface patterns. The insightful finite element analysis well demonstrates that the magnitude and distribution of internal stress in the ANPU elastomer can be regulated by selectively gradient crosslinking, leading to polymer chains migrate from the exposed region to the unexposed region, thereby generating a diverse array of surface patterns. Additionally, the periodic surface patterns exhibit tunable structural color according to the different stretching states and are fully reversible over multiple cycles, opening up avenues for diverse applications such as smart displays, stretchable strain sensors, and anticounterfeiting devices.

8.
J Biomater Appl ; 38(7): 834-847, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38154025

RESUMEN

Elsinochrome A (EA) is a naturally occurring photosensitizer with potential applications in photodynamic therapy (PDT) for various malignancies. Despite its promising therapeutic properties, the poor solubility of EA hampers its effective utilization in clinical settings. To circumvent this limitation, we engineered four distinct nano-formulations: PLGA/EA nanoparticles (NPs), CMC-PLGA/EA NPs, mPEG-PCL/EA nanomicelles (NMs), and LHP-CHOL/EA nanoliposomes (NLs), all designed to enhance the solubility of EA. A comparative evaluation of these formulations, based on metrics such as particle size, Zeta potential, drug loading efficiency, and encapsulation efficiency, identified PLGA/EA NPs and mPEG-PCL/EA NMs as the most efficacious candidates. Subsequent in vitro investigations into the drug release kinetics under varying pH conditions and the impact on cell viability and apoptosis in A549 and MCF-7 cell lines were conducted. Remarkably, the maximum drug release for PLGA/EA NPs and mPEG-PCL/EA NMs was recorded at 62.5% and 70.8% in an acidic environment (pH 5.7), respectively. Upon exposure to 460 nm light, PLGA/EA NPs induced a significant reduction in A549 cell viability to 13.8% and an apoptosis rate of 93.8%, whereas mPEG-PCL/EA NMs elicited a decrease in MCF-7 cell viability to 12.8% and an apoptosis rate of 73.0%.


Asunto(s)
Portadores de Fármacos , Nanopartículas , Perileno/análogos & derivados , Quinonas , Humanos , Portadores de Fármacos/química , Poliésteres/química , Polietilenglicoles/química , Nanopartículas/química , Tamaño de la Partícula
9.
J Cell Biochem ; 124(9): 1346-1365, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37555580

RESUMEN

Elsinochrome A (EA) is a perylene quinone natural photosensitizer, photosensitizer under light excitation generates reactive oxygen species (ROS) to induce apoptosis, so can be used for treating tumors, that is so-called photodynamic therapy (PDT). However, the molecular mechanism, especially related to apoptosis and autophagy, is still unclear. In this study, we aimed to explore the mechanism of EA-PDT-induced B16 cells apoptosis and autophagy. The action of EA-PDT on mitochondrial permeability transition pore (MPTP), mitochondrial membrane potential (MMP) and the mitochondrial function were researched by fluorescence technique and Extracellular Flux Analyzer. Illumina sequencing, tandem mass tags Quantitative Proteomics and Western Blot studied the mechanism at the gene and protein levels. The results indicated that EA-PDT had excellent phototoxicity in vitro. EA could bind to the mitochondria. EA-PDT for 5 min caused MPTP opening, MMP decreasing and abnormal mitochondrial function with a concentration-dependent characteristic. EA-PDT resulted in an increase intracellular ROS and the number of autophagosomes. Caspase2, caspase9 and tnf were upregulated, and bcl2, prkn, atg2, atg9 and atg10 were downregulated. Our results indicated that EA-PDT induced cell apoptosis and autophagy through the mediation of ROS/Atg/Parkin. This study can provide enlightenment for exploring potential targets of drug development for the PDT of melanoma.


Asunto(s)
Fotoquimioterapia , Fármacos Fotosensibilizantes , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Fotoquimioterapia/métodos , Especies Reactivas de Oxígeno/metabolismo , Línea Celular Tumoral , Apoptosis , Autofagia
10.
Sci Total Environ ; 897: 165429, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37437627

RESUMEN

The bright coniferous forest area in the cold temperate zone of China is a terrestrial ecosystem primarily dominated by low mountain Larix gmelinii trees. Limited information is available regarding the assembly mechanisms and interactions of microbial communities in the soil in this region. This study employed high-throughput techniques to obtain DNA from myxomycetes, bacteria, and fungi in the soil, evaluated their diversity in conjunction with environmental factors, associated them with the assembly process, and explored the potential interaction relationships between these microorganisms. The findings of our study showed that environmental factors had a more significant influence on the α and ß diversity of bacteria compared to myxomycetes and fungi. Microbial communities were influenced by environmental selection and geographical diffusion, although environmental selection appeared to have a more significant impact than geographical diffusion. Our study suggested that different microorganisms exhibited unique evolutionary patterns and may have different assembly modes within phylogenetic groups. Myxomycetes and fungi exhibited a similar assembly process that was mainly influenced by stochastic dispersal limitation and drift. In contrast, bacteria's assembly process was primarily influenced by stochastic drift and deterministic homogeneous selection. The community of myxomycetes and fungi is greatly influenced by spatial distribution and random events, while bacteria have a relatively stable population composition in specific regions and may also be subject to environmental constraints. Finally, this study revealed that Humicolopsis cephalosporioides, a fungus that exclusively resided in cold environments, may play a critical role as a keystone species in maintaining molecular ecological networks and was considered a core member of the microbiome.


Asunto(s)
Suelo , Tracheophyta , Ecosistema , Filogenia , Microbiología del Suelo , Bosques , Hongos
11.
Sci Bull (Beijing) ; 67(21): 2186-2195, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36545994

RESUMEN

Regulating metal surfaces with micro-/nanoscale structures is of great significance for both material science and potential applications. However, the intrinsic properties of metals, such as fixed isotropic moduli and inflexible structures, in a sense present major limitations in developing next-generation smart patterned surfaces. In this work, a facile and general patterning strategy is proposed to endow insensitive metal surfaces with controllable spontaneous topologies and dynamic performance by exquisitely introducing an essential photosensitive interlayer. The arresting anthracene-containing photocrosslinking interlayer can selectively predetermine the anisotropic property of compliant bilayers without damaging metals' homogeneous properties, and realize a changeable stiff/soft layer. Furthermore, the mechanical transition mechanism of the self-adaptive wrinkling modes in metal-based trilayer systems is revealed to pave the pathway for regulating functional wrinkled metal surfaces. This photodriven metal patterning strategy can promote the development of brand-new methods for tuning the instability of multilayered materials, and be potentially applied in smart optical devices with dynamic reflectance, including light gratings and "magic" mirrors.

12.
Nat Commun ; 13(1): 7434, 2022 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-36460720

RESUMEN

Stress relaxation in reconfigurable supramolecular polymer networks is strongly related to intermolecular behavior. However, the relationship between molecular motion and macroscopic mechanics is usually vague, and the visualization of internal stress reflecting precise regulation of molecules remains challenging. Here, we present a strategy for visualizing photo-driven stress relaxation induced by infinitesimal perturbations in the intermolecular exchange reaction via reprogrammable wrinkle patterns. The supramolecular films exhibit visible changes in microscopic wrinkle topography through ultraviolet (UV)-induced dynamic disulfide exchange reaction. In accordance with the trans-scale theoretical models, which quantitatively evaluate the chemical-dependent mechanical stresses in the supramolecular network, the unexposed disordered wrinkles evolved into highly oriented patterns and underwent subsequent mutations after thermal treatment. The stress-sensitive wrinkle macro-patterns can be repetitively written/erased through network topology rearrangement using different stimuli. This strategy provides an approach for visualizing and understanding the molecular behavior from dynamic chemistry to mechanical changes, and directly programming wrinkle patterns with regulated structures.


Asunto(s)
Disulfuros , Películas Cinematográficas , Humanos , Aberraciones Cromosómicas , Movimiento (Física) , Mutación
13.
Mater Horiz ; 9(12): 3078-3086, 2022 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-36263734

RESUMEN

Incorporating a pattern-memorizing surface into a multi-functional shape memory polymer (SMP) offers various extraordinary opportunities for their engineering applications. However, current memory-patterned approaches prepared by artificial loading are at the cost of initial balance, whose potential is greatly limited by the internal relationship between thermodynamic equilibrium and the entropy-driven pattern-memorizing cycle. Here, a robust yet effective strategy is presented for fabricating a spontaneous pattern on a poly(styrene-block-butadiene-block-styrene) (SBS)-based SMP with a gradient crosslinking network via molecular diffusion for equilibrium. Benefiting from the photo-induced diffusion of maleimide, the resulting steady-state pattern as a permanent shape ensures the recovery of morphology, and the gradient network formed by the diffusion-regulated spatial Diels-Alder (D-A) crosslinking reaction makes the pattern memory cycle from existence to elimination possible. Furthermore, taking advantage of an uneven structural network, the shape reconfigurations from 2D patterned sheets to 3D configurations with a patterned surface can be achieved conveniently through a shape memory effect, simplifying programming setups. In addition, this type of 3D shape also can shift back to a 2D patterned film via an inverse D-A decrosslinking reaction upon thermal treatment. This straightforward approach for fabricating a pattern of a single layer on an SMP surface with a spatial gradient network opens a new avenue for functional smart materials, which expands the technological perspectives in many fields of flexible electronics, smart actuators, switching sensors and soft robotics.

14.
J Fungi (Basel) ; 8(8)2022 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-36012829

RESUMEN

Biofilm-associated Candida albicans infections, the leading cause of invasive candidiasis, can cause high mortality rates in immunocompromised patients. Photodynamic antimicrobial chemotherapy (PACT) is a promising approach for controlling infections caused by biofilm-associated C. albicans. This study shows the effect of Elsinochrome A (EA) against different stages of C. albicans biofilms in vitro by XTT reduction assay and crystal violet staining. The mechanism of action of EA on C. albicans biofilm was analyzed with flow cytometry, confocal laser microscopy, and the Real-Time Quantitative Reverse Transcription PCR (qRT-PCR). EA-mediated PACT significantly reduced the viability of C. albicans, with an inhibition rate on biofilm of 89.38% under a concentration of 32 µg/mL EA. We found that EA could not only inhibit the adhesion of C. albicans in the early stage of biofilm formation, but that it also had good effects on pre-formed mature biofilms with a clearance rate of 35.16%. It was observed that EA-mediated PACT promotes the production of a large amount of reactive oxygen species (ROS) in C. albicans and down-regulates the intracellular expression of oxidative-stress-related genes, which further disrupted the permeability of cell membranes, leading to mitochondrial and nuclear damage. These results indicate that EA has good photodynamic antagonizing activity against the C. albicans biofilm, and potential clinical value.

15.
Accid Anal Prev ; 169: 106633, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35278847

RESUMEN

INTRODUCTION: Despite demonstrated effectiveness of child restraint system (CRS), its use in China is extremely low due to the lack of national legislation requiring the use of CRS, as well as lack of child passenger safety knowledge among caregivers. Implementing an effective intervention is urgently needed to promote the use of CRS. In this study, we primarily evaluated the effectiveness of biomechanical visualization delivered in the context of CRS education to promote CRS use. METHODS: We conducted a cluster randomised controlled trial to test the effects of educational intervention programs on increased use of CRS. Participants included caregivers from 8 pre-schools located in two cities (i.e., Chaozhou and Shantou) in China. Following a baseline survey, 8 pre-schools were randomly assigned into 1 of 4 groups with 2 schools in each group: 1) CRS education-only, 2) CRS education with behavioral skill training, 3) CRS education with biomechanical visualization, and 4) control. The primary outcome was CRS use, and the secondary outcomes included scores of child passenger safety-related knowledge and CRS use-related attitudes. The effect of the intervention was assessed among caregivers at two time points: baseline preintervention and 6 months postintervention. RESULTS: More than 70% caregivers had never used CRS at baseline. No statistically significant between-group differences CRS use were observed at baseline preintervention (34.2%, 25.4%, 29.6% and 21.9%, respectively, P = 0.18). However, compared to the control group, odds of CRS non-use was significantly lower in caregivers assigned to the CRS education with biomechanical visualization (adjusted odd ratio (AOR) = 0.11, 95% confidence interval (CI) = 0.07-0.17), CRS education with behavioral skill training (AOR = 0.15, 95%CI = 0.10-0.24) and CRS education-only (AOR = 0.26, 95%CI = 0.17-0.41) groups, respectively. Statistically significant differences were also observed in the secondary outcomes postintervention across groups. Specifically, the CRS education with biomechanical visualization and CRS education with behavioral skill training groups had higher mean knowledge change scores than the CRS education-only group (3.3 ± 1.5 vs. 2.9 ± 2.2, p = 0.035 and 3.2 ± 1.9 vs. 2.9 ± 2.2, p = 0.039, respectively). We also observed a significantly higher increase in the attitudes scores in the CRS education with biomechanical visualization group compared with the CRS education-only group (4.7 ± 2.1 vs. 3.5 ± 2.8,p = 0.026). CONCLUSIONS: This study shows that both biomechanical visualization and behavioral skill training supplements to education improved understanding of CRS knowledge compared to education only, and all three strategies led to increased CRS use. Importantly, CRS education with biomechanical visualization was shown to be more effective than CRS education alone in improving caregiver's knowledge and attitudes. The use of biomechanical visualization may be an effective supplement to traditional education programs.


Asunto(s)
Accidentes de Tránsito , Sistemas de Retención Infantil , Niño , Preescolar , Humanos , Padres/educación , Instituciones Académicas , Encuestas y Cuestionarios
16.
PeerJ ; 9: e12059, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34527444

RESUMEN

Although myxomycetes are ubiquitous in terrestrial ecosystems, studies on their distribution and diversity in subtropical humid forests are still lacking. Field collections and moist chamber cultures were conducted from May to October within a two-year period in the Tiantangzhai National Forest Park of China. A total of 1,492 records representing 73 species belonging to 26 genera were obtained, of which 243 records/37 species were from field collections, and 1,249 records/52 species were from moist chamber cultures. Among the specimens obtained by culturing, 896 records/38 species and 353 records/37 species were obtained from living bark and ground litter, respectively. ANOVA showed that the sampling months had significant impacts on collection of myxomycetes from field and those that inhabit litter. An LEfSe analysis indicated that Arcyria was significantly abundant in August, while Stemonitis and Physarum were more abundant in July when collected from field. An RDA analysis showed that temperature was the main factor that affected the litter-inhabiting myxomycetes. The ANOVA indicated that forest type was the significant factor for bark-inhabiting myxomycetes. Diderma effusum was primarily obtained from mixed forests, while Clastoderma debaryanum and Colloderma oculatum were more common in coniferous forests. The RDA analysis indicated that the vegetation, pH, water retention, and elevation were the primary factors that affected the bark-inhabiting myxomycetes.

17.
Sci Rep ; 11(1): 2365, 2021 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-33504905

RESUMEN

Shiraia bambusicola has been used as a traditional Chinese medicine for a long history. Its major medicinal active metabolites are perylenequinones, including hypocrellin A, elsinochrome A and so on. At present, the fermentation yield of perylenequinones is low, and its complex biosynthesis and regulatory pathways are still unclear. In this study, nitric oxide, as a downstream signal molecule of hydrogen peroxide, regulates the biosynthesis of perylenequinones. Exogenous addition of 0.01 mM sodium nitroprusside (nitric oxide donor) can promote perylenequinones production by 156% compared with the control. Further research found that hydrogen peroxide and nitric oxide increased the transcriptional level of the biosynthetic genes of hypocrellin A. The results showed that nitric oxide is involved in the biosynthesis and regulation of perylenequinones in Shiraia bambusicola as a signal molecule. In the future, the yield of perylenequinones can be increased by adding exogenous nitric oxide in fermentation.


Asunto(s)
Ascomicetos/efectos de los fármacos , Ascomicetos/metabolismo , Peróxido de Hidrógeno/farmacología , Óxido Nítrico/farmacología , Perileno/análogos & derivados , Quinonas/metabolismo , Perileno/metabolismo , Fenol/metabolismo
18.
Inj Prev ; 27(1): 42-47, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-31915269

RESUMEN

OBJECTIVES: To examine the patterns and associated factors of road traffic injuries (RTIs) involving autonomous vehicles (AVs) and to discuss the public health implications and challenges of autonomous driving. METHODS: Data were extracted from the reports of traffic crashes involving AVs. All the reports were submitted to the California Department of Motor Vehicles by manufacturers with permission to operate AV test on public roads. Descriptive analysis and χ2 analysis or Fisher's exact test was conducted to describe the injury patterns and to examine the influencing factors of injury outcomes, respectively. Binary logistic regression using the Wald test was employed to calculate the OR, adjusted OR (AOR) and 95% CIs. A two-tailed probability (p<0.05) was adopted to indicate statistical significance. RESULTS: 133 reports documented 24 individuals injured in 19 crashes involving AVs, with the overestimated incidence rate of 18.05 per 100 crashes. 70.83% of the injured were AV occupants, replacing vulnerable road users as the leading victims. Head and neck were the most commonly injured locations. Driving in poor lighting was at greater risk of RTIs (AOR 6.37, 95% CI 1.47 to 27.54). Collisions with vulnerable road users or incidents happening during commute periods led to a greater number of victims (p<0.05). Autonomous mode cannot perform better than conventional mode in road traffic safety to date (p=0.468). CONCLUSIONS: Poor lighting improvement and the regulation of commute-period traffic and vulnerable road users should be strengthened for AV-related road safety. So far AVs have not demonstrated the potential to dramatically reduce RTIs. Cautious optimism about AVs is more advisable, and multifaceted efforts, including legislation, smarter roads, and knowledge dissemination campaigns, are fairly required to accelerate the development and acceptance.


Asunto(s)
Conducción de Automóvil , Heridas y Lesiones , Accidentes de Tránsito , Humanos , Vehículos a Motor , Probabilidad , Salud Pública , Heridas y Lesiones/epidemiología
19.
Front Microbiol ; 11: 643, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32373091

RESUMEN

Shiraia bambusicola has long been used as a traditional Chinese medicine and its major medicinal active metabolite is hypocrellin, which exhibits outstanding antiviral and antitumor properties. Here we report the 32 Mb draft genome sequence of S. bambusicola S4201, encoding 11,332 predicted genes. The genome of S. bambusicola is enriched in carbohydrate-active enzymes (CAZy) and pathogenesis-related genes. The phylogenetic tree of S. bambusicola S4201 and nine other sequenced species was constructed and its taxonomic status was supported (Pleosporales, Dothideomycetes). The genome contains a rich set of secondary metabolite biosynthetic gene clusters, suggesting that strain S4201 has a remarkable capacity to produce secondary metabolites. Overexpression of the zinc finger transcription factor zftf, which is involved in hypocrellin A (HA) biosynthesis, increases HA production when compared with wild type. In addition, a new putative HA biosynthetic pathway is proposed. These results provide a framework to study the mechanisms of infection in bamboo and to understand the phylogenetic relationships of S. bambusicola S4201. At the same time, knowledge of the genome sequence may potentially solve the puzzle of HA biosynthesis and lead to the discovery of novel genes and secondary metabolites of importance in medicine and agriculture.

20.
BMC Public Health ; 20(1): 807, 2020 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-32471397

RESUMEN

BACKGROUND: Child passenger safety is an important public health problem in China. This study aimed to examine the prevalence of child passenger restraint use while riding in a car in the city of Shantou in China from 2012 to 2017. METHODS: Three large-scale cross-sectional observational studies were conducted in 2012, 2015 and 2017, respectively. The observation sites included randomly selected hospitals, kindergartens, and primary and secondary schools. The outcome measures included the changes in percentages of seating position (e.g., front vs. rear), whether sitting on lap, and use of child restraint systems (CRS) or seat belts by year and by age group. Descriptive statistics, Chi-square tests and logistic regression were used to address the study aims. RESULTS: A total of 9858 commuting children aged 17 and younger were observed in passenger cars in Shantou, China during the study. The proportion of children aged 0-5 sitting on adult's lap decreased from 26.6% in 2012 to 24.6% in 2017, while the proportion of CRS use among the children sitting in the rear row increased among children aged 0-5 (from 0.7% in 2012 to 14.2% in 2017) and children aged 6-11 (from 0.7% in 2012 to 2.4% in 2017). Comparing children aged 0-11 in 2012, children in the same ages were less likely to sit in the front row in 2015 (OR = 0.42, 95%CI = 0.37, 0.48) and in 2017 (OR = 0.27, 95%CI = 0.23, 0.31). Children aged 0-11 were more likely to sit in the rear row with CRS use in 2015 (OR = 8.50, 95%CI = 5.44, 13.28) and in 2017 (OR = 10.95, 95%CI = 7.02, 17.08) comparing with children in the same ages in 2012. As for children aged 12-17, they were more likely to use seat belt in 2017 (OR = 1.40, 95%CI = 1.06, 1.85) compared with those children in 2012. CONCLUSIONS: While child passenger safety behaviors improved from 2012 to 2017 in Shantou, China, more efforts are needed to protect child passengers from injuries.


Asunto(s)
Conducción de Automóvil/estadística & datos numéricos , Sistemas de Retención Infantil/estadística & datos numéricos , Sistemas de Retención Infantil/tendencias , Cinturones de Seguridad/estadística & datos numéricos , Cinturones de Seguridad/tendencias , Adolescente , Niño , Preescolar , China , Estudios Transversales , Femenino , Predicción , Humanos , Lactante , Recién Nacido , Modelos Logísticos , Masculino , Prevalencia
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