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1.
Org Biomol Chem ; 22(23): 4667-4671, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38804830

RESUMEN

Iodine is one of the most effective sources for iodination of aromatic compounds; however, its electrophilicity is insufficient for direct iodination. The selection of appropriate environmentally friendly and cost-effective oxidants in combination with iodine for the iodination of aromatic rings, along with its application in the synthesis of natural products, holds significant importance. A highly efficient method utilizing I(III) as the initiator has been successfully developed for monoiodination of arylaldehydes. The method demonstrates good compatibility with a wide range of (hetero)aromatic aldehydes, resulting in moderate to excellent yields, without the need for any toxic, volatile or explosive reagents. The synthesis of seven natural products, namely aristogins A-F and hernandial, was achieved through this iodination followed by Ullmann-type coupling.

2.
J Environ Manage ; 360: 121185, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38788407

RESUMEN

Chlorophyll fluorescence is the long-wave light released by the residual energy absorbed by vegetation after photosynthesis and dissipation, which can directly and non-destructively reflect the photosynthetic state of plants from the perspective of the mechanism of photosynthetic process. Moso bamboo has a substantial carbon sequestration ability, and leaf-expansion stage is an important phenological period for carbon sequestration. Gross primary production (GPP) is a key parameter reflecting vegetation carbon sequestration process. However, the ability of chlorophyll fluorescence in moso bamboo to explain GPP changes is unclear. The research area of this study is located in the bamboo forest near the flux station of Anji County, Zhejiang Province, where an observation tower is built to monitor the carbon flux and meteorological change of bamboo forest. The chlorophyll fluorescence physiological parameters (Fp) and fluorescence yield (Fy) indices were measured and calculated for the leaves of newborn moso bamboo (I Du bamboo) and the old leaves of 4- to 5-year-old moso bamboo (Ⅲ Du bamboo) during the leaf-expansion stage. The chlorophyll fluorescence in response to the environment and its effect on carbon flux were analyzed. The results showed that: Fv/Fm, Y(II) and α of Ⅰ Du bamboo gradually increased, while Ⅲ Du bamboo gradually decreased, and FYint and FY687/FY738 of Ⅰ Du bamboo were higher than those of Ⅲ Du bamboo; moso bamboo was sensitive to changes in air temperature(Ta), relative humidity(RH), water vapor pressure(E), soil temperature(ST) and soil water content (SWC), the Fy indices of the upper, middle and lower layers were significantly correlated with Ta, E and ST; single or multiple vegetation indices were able to estimate the fluorescence yield indices well (all with R2 greater than 0.77); chlorophyll fluorescence (Fp and Fy indices) of Ⅰ Du bamboo and Ⅲ Du bamboo could explain 74.4% and 72.7% of the GPP variation, respectively; chlorophyll fluorescence and normalized differential vegetation index of the canopy (NDVIc) could estimate GPP well using random forest (Ⅰ Du bamboo: r = 0.929, RMSE = 0.069 g C·m-2; Ⅲ Du bamboo: r = 0.899, RMSE = 0.134 g C·m-2). The results of this study show that chlorophyll fluorescence can provide a basis for judging the response of moso bamboo to environmental changes and can well explain GPP. This study has important scientific significance for evaluating the potential mechanisms of growth, stress feedback and photosynthetic carbon sequestration of bamboo.


Asunto(s)
Clorofila , Fotosíntesis , Hojas de la Planta , Clorofila/metabolismo , Hojas de la Planta/metabolismo , Fluorescencia , Poaceae/metabolismo , Poaceae/crecimiento & desarrollo , Secuestro de Carbono , Carbono/metabolismo
3.
BMC Genomics ; 24(1): 389, 2023 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37430218

RESUMEN

BACKGROUND: The development of asymmetric chick gonads involves separate developmental programs in the left and right gonads. In contrast to the left ovary developing into a fully functional reproductive organ, the right ovary undergoes gradual degeneration. However, the molecular mechanisms underlying the the degeneration of the right ovary remain incompletely understood. In the present study, we investigated the histomorphological and transcriptomic changes in the right ovary of ducks and geese during the the embryonic stage up to post-hatching day 1. RESULT: Hematoxylin-eosin stainings revealed that the right ovary developed until embryonic day 20 in ducks (DE20) or embryonic day 22 in geese (GE22), after which it started to regress. Further RNA-seq analyses revealed that both the differentially expressed genes (DEGs) in ducks and geese right ovary developmental stage were significantly enriched in cell adhesion-related pathway (ECM-receptor interaction, Focal adhesion pathway) and Cellular senescence pathway. Then during the degeneration stage, the DEGs were primarily enriched in pathways associated with inflammation, including Herpes simplex virus 1 infection, Influenza A, and Toll-like receptor signaling pathway. Moreover, duck-specific DEGs showed enrichment in Steroid hormone biosynthesis, Base excision repair, and the Wnt signaling pathway, while geese-specifically DEGs were found to be enriched in apoptosis and inflammation-related pathways, such as Ferroptosis, Necroptosis, RIG-I-like receptor signaling pathway, and NOD-like receptor signaling pathway. These findings suggest that the degeneration process of the right ovary in ducks occurs at a slower pace compared to that in geese. Additionally, the observation of the left ovary of the geese varying degeneration rates in the right ovary after hatching indicated that the development of the left ovary may be influenced by the degeneration of the right ovary. CONCLUSION: The data presented in this study provide valuable insights into the dynamic changes in histological structure and transcriptome during the degeneration of the right ovary in ducks and geese. In addition, through the analysis of shared characteristics in the degeneration process of the right ovary in both ducks and geese, we have uncovered the patterns of degradation and elucidated the molecular mechanisms involved in the regression of the right ovary in poultry. Furthermore, we have also made initial discoveries regarding the relationship between the degeneration of the right ovary and the development of the left ovary.


Asunto(s)
Patos , Ovario , Femenino , Animales , Patos/genética , Gansos/genética , Transcriptoma , Inflamación
4.
Bioinformatics ; 38(6): 1716-1723, 2022 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-34999771

RESUMEN

MOTIVATION: Recently, with the development of high-throughput experimental technology, reconstruction of gene regulatory network (GRN) has ushered in new opportunities and challenges. Some previous methods mainly extract gene expression information based on RNA-seq data, but the associated information is very limited. With the establishment of gene expression image database, it is possible to infer GRN from image data with rich spatial information. RESULTS: First, we propose a new convolutional neural network (called SDINet), which can extract gene expression information from images and identify the interaction between genes. SDINet can obtain the detailed information and high-level semantic information from the images well. And it can achieve satisfying performance on image data (Acc: 0.7196, F1: 0.7374). Second, we apply the idea of our SDINet to build an RNA-model, which also achieves good results on RNA-seq data (Acc: 0.8962, F1: 0.8950). Finally, we combine image data and RNA-seq data, and design a new fusion network to explore the potential relationship between them. Experiments show that our proposed network fusing two modalities can obtain satisfying performance (Acc: 0.9116, F1: 0.9118) than any single data. AVAILABILITY AND IMPLEMENTATION: Data and code are available from https://github.com/guofei-tju/Combine-Gene-Expression-images-and-RNA-seq-data-For-infering-GRN.


Asunto(s)
Redes Reguladoras de Genes , Expresión Génica , RNA-Seq , Análisis de Secuencia de ARN/métodos
5.
J Nanobiotechnology ; 21(1): 119, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-37020301

RESUMEN

BACKGROUND: Sustained release of bioactive BMP2 (bone morphogenetic protein-2) is important for bone regeneration, while the intrinsic short half-life of BMP2 at protein level cannot meet the clinical need. In this study, we aimed to design Bmp2 mRNA-enriched engineered exosomes, which were then loaded into specific hydrogel to achieve sustained release for more efficient and safe bone regeneration. RESULTS: Bmp2 mRNA was enriched into exosomes by selective inhibition of translation in donor cells, in which NoBody (non-annotated P-body dissociating polypeptide, a protein that inhibits mRNA translation) and modified engineered BMP2 plasmids were co-transfected. The derived exosomes were named ExoBMP2+NoBody. In vitro experiments confirmed that ExoBMP2+NoBody had higher abundance of Bmp2 mRNA and thus stronger osteogenic induction capacity. When loaded into GelMA hydrogel via ally-L-glycine modified CP05 linker, the exosomes could be slowly released and thus ensure prolonged effect of BMP2 when endocytosed by the recipient cells. In the in vivo calvarial defect model, ExoBMP2+NoBody-loaded GelMA displayed great capacity in promoting bone regeneration. CONCLUSIONS: Together, the proposed ExoBMP2+NoBody-loaded GelMA can provide an efficient and innovative strategy for bone regeneration.


Asunto(s)
Exosomas , Hidrogeles , Regeneración Ósea , Preparaciones de Acción Retardada/metabolismo , Exosomas/metabolismo , Hidrogeles/farmacología , Osteogénesis , ARN Mensajero/metabolismo , Proteína Morfogenética Ósea 2/metabolismo
6.
Anal Chem ; 93(2): 946-955, 2021 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-33206502

RESUMEN

Nonspecific binding and weak spectral discernment are the main challenges for surface-enhanced Raman scattering (SERS) detection, especially in real sample analysis. Herein, molecularly imprinted polymer (MIP)-based core-shell AuNP@polydopamine (AuNP@PDA-MIP) nanoparticles (NPs) are designed and immobilized on an electrochemically reduced MoS2-modified screen-printed electrode (SPE). This portable electrochemical-Raman interface offers the dual functions of electrokinetic preseparation (EP) and MIP trapping of charged molecules so that a reliable SERS recognition with molecular selectivity and high sensitivity can be achieved. Core-shell AuNP@PDA-MIP NPs can be controllably synthesized, possess predesigned specific recognition, and provide "hot spots" at the junction of NPs. The introduction of an electric field enables the autonomous exclusion and separation of similarly charged molecules as well as attraction and concentration of the oppositely charged molecules by electrostatic attraction. Subsequently, the specific MIP recognition cavities allow selective adsorption of targets on the interface without the interference of analogues. Owing to the distinctive design of the multiple coupling separation, trapping, and enrichment strategies, the MIP-based SERS-active interface can be used for label-free detection of charged molecules in real samples without pretreatment. As a proof-of-concept study, label-free SERS detection of charged phthalate plasticizers (PAEs) was demonstrated with a detection limit as low as 2.7 × 10-12 M for dimethyl phthalate (DMP) and 2.3 × 10-11 M for di(2-ethylhexyl) phthalate (DEHP). This sensing strategy for in situ SERS analysis of charged pollutants or toxins holds vast promises for a wide range of in-field applications.


Asunto(s)
Impresión Molecular , Ácidos Ftálicos/análisis , Plastificantes/análisis , Oro/química , Indoles/química , Estructura Molecular , Nanopartículas/química , Tamaño de la Partícula , Polímeros/química , Espectrometría Raman , Propiedades de Superficie
7.
Molecules ; 26(15)2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34361712

RESUMEN

The genus Maytenus is a member of the Celastraceae family, of which several species have long been used in traditional medicine. Between 1976 and 2021, nearly 270 new compounds have been isolated and elucidated from the genus Maytenus. Among these, maytansine and its homologues are extremely rare in nature. Owing to its unique skeleton and remarkable bioactivities, maytansine has attracted many synthetic endeavors in order to construct its core structure. In this paper, the current status of the past 45 years of research on Maytenus, with respect to its chemical and biological activities are discussed. The chemical research includes its structural classification into triterpenoids, sesquiterpenes and alkaloids, along with several chemical synthesis methods of maytansine or maytansine fragments. The biological activity research includes activities, such as anti-tumor, anti-bacterial and anti-inflammatory activities, as well as HIV inhibition, which can provide a theoretical basis for the better development and utilization of the Maytenus.


Asunto(s)
Alcaloides/química , Maitansina/análogos & derivados , Maytenus/química , Fitoquímicos/química , Sesquiterpenos/química , Triterpenos/química , Alcaloides/clasificación , Alcaloides/aislamiento & purificación , Alcaloides/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Fármacos Anti-VIH/química , Fármacos Anti-VIH/aislamiento & purificación , Fármacos Anti-VIH/farmacología , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/farmacología , Humanos , Maitansina/aislamiento & purificación , Maitansina/farmacología , Maytenus/metabolismo , Estructura Molecular , Fitoquímicos/clasificación , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Plantas Medicinales , Sesquiterpenos/clasificación , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/farmacología , Relación Estructura-Actividad , Triterpenos/clasificación , Triterpenos/aislamiento & purificación , Triterpenos/farmacología
8.
J Environ Manage ; 248: 109265, 2019 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-31352276

RESUMEN

Understanding the impact and restriction of climate change on potential distribution of bamboo forest is crucial for sustainable management of bamboo forest and bamboo-based economic development. In this study, climatic variables and maximum entropy model were used to simulate the potential distribution of bamboo forest in China under the future climate scenarios. Seven climatic variables, such as Spring precipitation, Summer precipitation, Autumn precipitation, average annual relative humidity, Autumn average temperature, average annual temperature range and annual total radiation, were selected as input variables of maximum entropy model based on the relative importance of those climate variables for predicting bamboo forest presence. The suitable ranges of the seven climatic variables for potential distribution of bamboo forest were 337-794 mm, 496-705 mm, 213-929 mm, 74.3%-83.4%, 16.6-23.8 °C, 2.3-10.1 °C and 3.2 × 104-4.3 × 104 W m-2, respectively. Under RCP4.5 and RCP8.5 climate scenarios, the suitable area of bamboo forest growth first increased and then decreased, and showed range contractions towards the interior and expansions towards southwest in China. The results of the present study can serve as a useful reference to dynamic monitoring of the spatial distribution and sustainable utilization of bamboo forest in the future under climate change.


Asunto(s)
Cambio Climático , Bosques , China , Estaciones del Año , Temperatura
9.
Nanotechnology ; 29(36): 365301, 2018 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-29901454

RESUMEN

Chemical vapor deposited graphene suffers from two problems: transfer from metal catalysts to insulators, and photoresist induced degradation during patterning. Both result in macroscopic and microscopic damages such as holes, tears, doping, and contamination, translated into property and yield dropping. We attempt to solve the problems simultaneously. A nickel thin film is evaporated on SiO2 as a sacrificial catalyst, on which surface graphene is grown. A polymer (PMMA) support is spin-coated on the graphene. During the Ni wet etching process, the etchant can permeate the polymer, making the etching efficient. The PMMA/graphene layer is fixed on the substrate by controlling the surface morphology of Ni film during the graphene growth. After etching, the graphene naturally adheres to the insulating substrate. By using this method, transfer-free, lithography-free and fast growth of graphene realized. The whole experiment has good repeatability and controllability. Compared with graphene transfer between substrates, here, no mechanical manipulation is required, leading to minimal damage. Due to the presence of Ni, the graphene quality is intrinsically better than catalyst-free growth. The Ni thickness and growth temperature are controlled to limit the number of layers of graphene. The technology can be extended to grow other two-dimensional materials with other catalysts.

10.
J Environ Manage ; 223: 713-722, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29975899

RESUMEN

Lei bamboo (Phyllostachys praecox) is widely distributed in southeastern China. We used eddy covariance to analyze carbon sequestration capacity of a Lei bamboo forest (2011-2013) and to identify the seasonal biotic and abiotic determinants of carbon fluxes. A machine learning algorithm called random forest (RF) was used to identify factors that affected carbon fluxes. The RF model predicted well the gross ecosystem productivity (GEP), ecosystem respiration (RE) and net ecosystem exchange (NEE), and displayed variations in the drivers between different seasons. Mean annual NEE, RE, and GEP were -105.2 ±â€¯23.1, 1264.5 ±â€¯45.2, and 1369.6 ±â€¯52.5 g C m-2, respectively. Climate warming increased RE more than GEP when water inputs were not limiting. Summer drought played little role in suppressing GEP, but low soil moisture contents suppressed RE and increased the carbon sink during drought in the summer. The most important drivers of NEE were soil temperature in spring, summer, and winter, and photosynthetically active radiation in autumn. Air and soil temperature were important drivers of GEP in all seasons.


Asunto(s)
Ciclo del Carbono , Secuestro de Carbono , Ecosistema , Modelos Teóricos , Carbono , Dióxido de Carbono , China
11.
J Sep Sci ; 40(14): 2933-2940, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28556490

RESUMEN

The extraction adsorbent was fabricated by immobilizing the highly specific recognition and binding of aptamer onto the surface of Fe3 O4 magnetic nanoparticles, which not only acted as recognition elements to recognize and capture the target molecule berberine from the extract of Cortex phellodendri, but also could favor the rapid separation and purification of the bound berberine by using an external magnet. The developed solid-phase extraction method in this work was useful for the selective extraction and determination of berberine in Cortex phellodendri extracts. Various conditions such as the amount of aptamer-functionalized Fe3 O4 magnetic nanoparticles, extraction time, temperature, pH value, Mg2+ concentration, elution time and solvent were optimized for the solid-phase extraction of berberine. Under optimal conditions, the purity of berberine extracted from Cortex phellodendri was as high as 98.7% compared with that of 4.85% in the extract, indicating that aptamer-functionalized Fe3 O4 magnetic nanoparticles-based solid-phase extraction method was very effective for berberine enrichment and separation from a complex herb extract. The applicability and reliability of the developed solid-phase extraction method were demonstrated by separating berberine from nine different concentrations of one Cortex phellodendri extract. The relative recoveries of the spiked solutions of all the samples were between 95.4 and 111.3%, with relative standard deviations ranging between 0.57 and 1.85%.


Asunto(s)
Berberina/aislamiento & purificación , Medicamentos Herbarios Chinos/química , Nanopartículas de Magnetita , Phellodendron/química , Reproducibilidad de los Resultados , Extracción en Fase Sólida
12.
J Clin Monit Comput ; 30(6): 807-820, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26392184

RESUMEN

Offline general-type models are widely used for patients' monitoring in intensive care units (ICUs), which are developed by using past collected datasets consisting of thousands of patients. However, these models may fail to adapt to the changing states of ICU patients. Thus, to be more robust and effective, the monitoring models should be adaptable to individual patients. A novel combination of just-in-time learning (JITL) and principal component analysis (PCA), referred to learning-type PCA (L-PCA), was proposed for adaptive online monitoring of patients in ICUs. JITL was used to gather the most relevant data samples for adaptive modeling of complex physiological processes. PCA was used to build an online individual-type model and calculate monitoring statistics, and then to judge whether the patient's status is normal or not. The adaptability of L-PCA lies in the usage of individual data and the continuous updating of the training dataset. Twelve subjects were selected from the Physiobank's Multi-parameter Intelligent Monitoring for Intensive Care II (MIMIC II) database, and five vital signs of each subject were chosen. The proposed method was compared with the traditional PCA and fast moving-window PCA (Fast MWPCA). The experimental results demonstrated that the fault detection rates respectively increased by 20 % and 47 % compared with PCA and Fast MWPCA. L-PCA is first introduced into ICU patients monitoring and achieves the best monitoring performance in terms of adaptability to changes in patient status and sensitivity for abnormality detection.


Asunto(s)
Cuidados Críticos/métodos , Unidades de Cuidados Intensivos , Monitoreo Fisiológico/instrumentación , Monitoreo Fisiológico/métodos , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Femenino , Humanos , Pacientes Internos , Aprendizaje , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Sistemas en Línea , Análisis de Componente Principal , Reproducibilidad de los Resultados , Procesamiento de Señales Asistido por Computador , Programas Informáticos
13.
Fa Yi Xue Za Zhi ; 31(6): 466-9, 2015 Dec.
Artículo en Zh | MEDLINE | ID: mdl-27141807

RESUMEN

Mild traumatic brain injury (MTBI) is defined as a mild brain trauma resulting in a short loss of consciousness and alteration of mental status. It may also occasionally develop persistent and progressive symptoms. It has been confirmed that MTBI causes changes of anatomic structures in central nervous system and biomarkers in the body fluid. However, there is no sufficient research on relevance among threshold for the brain injury, individual vulnerability and duration of disturbance of consciousness. Furthermore, there are no reliable diagnostic methods to establish whether a blow to the head is sufficient to cause the brain injury. This review provides references for biomarkers in cerebrospinal fluid and blood associated with TBI. It also provides application status and potential prospects for further assessment and diagnosis of MTBI.


Asunto(s)
Biomarcadores/sangre , Biomarcadores/líquido cefalorraquídeo , Lesiones Encefálicas/sangre , Lesiones Encefálicas/líquido cefalorraquídeo , Conmoción Encefálica/complicaciones , Lesiones Encefálicas/diagnóstico , Lesiones Encefálicas/etiología , Progresión de la Enfermedad , Humanos
14.
Front Microbiol ; 15: 1359949, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38500583

RESUMEN

Diabetic retinopathy (DR) is a prevalent microvascular complication in diabetic patients that poses a serious risk as it can cause substantial visual impairment and even vision loss. Due to the prolonged onset of DR, lengthy treatment duration, and limited therapeutic effectiveness, it is extremely important to find a new strategy for the treatment of DR. Postbiotic is an emerging dietary supplement which consists of the inactivate microbiota and its metabolites. Numerous animal experiments have demonstrated that intervention with postbiotics reduces hyperglycemia, attenuates retinal peripapillary and endothelial cell damage, improves retinal microcirculatory dysfunction, and consequently delays the progression of DR. More strikingly, unlike conventional probiotics and prebiotics, postbiotics with small molecules can directly colonize the intestinal epithelial cells, and exert heat-resistant, acid-resistant, and durable for storage. Despite few clinical significance, oral administration with postbiotics might become the effective management for the prevention and treatment of DR. In this review, we summarized the basic conception, classification, molecular mechanisms, and the advances in the therapeutic implications of postbiotics in the pathogenesis of DR. Postbiotics present great potential as a viable adjunctive therapy for DR.

15.
Front Microbiol ; 15: 1360225, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38450163

RESUMEN

Colorectal cancer (CRC) is a common malignancy affecting the gastrointestinal tract worldwide. The etiology and progression of CRC are related to factors such as environmental influences, dietary structure, and genetic susceptibility. Intestinal microbiota can influence the integrity of the intestinal mucosal barrier and modulate intestinal immunity by secreting various metabolites. Dysbiosis of the intestinal microbiota can affect the metabolites of the microbial, leading to the accumulation of toxic metabolites, which can trigger chronic inflammation or DNA damage and ultimately lead to cellular carcinogenesis and the development of CRC. Postbiotics are preparations of inanimate microorganisms or their components that are beneficial to the health of the host, with the main components including bacterial components (e.g., exopolysaccharides, teichoic acids, surface layer protein) and metabolites (e.g., short-chain fatty acids, tryptophan metabolite, bile acids, vitamins and enzymes). Compared with traditional probiotics, it has a more stable chemical structure and higher safety. In recent years, it has been demonstrated that postbiotics are involved in regulating intestinal microecology and improving the progression of CRC, which provides new ideas for the prevention and diagnosis of CRC. In this article, we review the changes in intestinal microbiota in different states of the gut and the mechanisms of anti-tumor activity of postbiotic-related components, and discuss the potential significance of postbiotics in the diagnosis and treatment of CRC. This reviews the changes and pathogenesis of intestinal microbiota in the development of CRC, and summarizes the relevant mechanisms of postbiotics in resisting the development of CRC in recent years, as well as the advantages and limitations of postbiotics in the treatment process of CRC.

16.
Sci Total Environ ; 913: 169439, 2024 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-38135074

RESUMEN

Net primary productivity (NPP) is an important indicator used to evaluate the carbon sequestration capacity of forest ecosystems. Subtropical forest ecosystems play an indispensable role in maintaining the global carbon balance, while frequently occurring drought events in recent years have seriously damaged their productivity. However, the spatiotemporal patterns of NPP, as well as its response to drought, remain uncertain. In this study, the multiscale drought characteristics in subtropical China during 1981-2015 were analyzed based on the standardized precipitation evapotranspiration index. Then, simulated and analyzed the spatiotemporal NPP of subtropical forests by the boreal ecosystem productivity simulator model. Finally, the response of NPP to drought was analyzed based on multiple statistical indices. The results show that most regions in subtropical China experienced mild and moderate drought during 1981-2015. In particular, the extent of drought severity has shown a noticeable increasing trend after 2000. The forest NPP ranged from 622.64 to 1323.82 gC·m-2·a-1, with an overall increase rate of 16.15 gC·m-2·a-1; in particular, the contribution of the western forest NPP became increasingly important. Drought stress has limited the growth of subtropical forest NPP in China, with summer and wet season time scales of drought having the greatest impact on forest NPP anomalies, followed by autumn time scales. The limitation is mostly because the drought duration continually increased, leading to differences in the impact of drought on forest NPP before and after 2000, with declines of 59.55 % and 82.45 %, respectively, mainly concentrated in southwestern regions, such as Yunnan, Guangxi, and Sichuan provinces. This study quantitatively analyzed the impact of drought on subtropical forest NPP, and provides scientific basis for subtropical forest response and adaptation to climate change.


Asunto(s)
Sequías , Ecosistema , China , Bosques , Incertidumbre , Cambio Climático
17.
Imeta ; 3(2): e192, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38882500

RESUMEN

In this work, we introduced a siderophore information database (SIDERTE), a digitized siderophore information database containing 649 unique structures. Leveraging this digitalized data set, we gained a systematic overview of siderophores by their clustering patterns in the chemical space. Building upon this, we developed a functional group-based method for predicting new iron-binding molecules with experimental validation. Expanding our approach to the collection of open natural products (COCONUT) database, we predicted a staggering 3199 siderophore candidates, showcasing remarkable structure diversity that is largely unexplored. Our study provides a valuable resource for accelerating the discovery of novel iron-binding molecules and advancing our understanding of siderophores.

18.
Front Vet Sci ; 11: 1394290, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38846790

RESUMEN

There is a gradual transition from water to dryland rearing of geese. In this study, we performed 16S rRNA sequencing (16S rRNA-seq) and transcriptome sequencing (RNA-seq) to reveal the effects of cage rearing (CR) and floor rearing (FR) systems on the microbial composition and transcriptome of the goose ileum. Through 16S rRNA-seq, Linear Discriminant Analysis Effect Size (LEfSe) analysis identified 2 (hgcI_clade and Faecalibacterium) and 14 (Bacteroides, Proteiniphilum, Proteiniclasticum, etc.) differential microbiota in CR and FR, respectively. The rearing system influenced 4 pathways including biosynthesis of amino acids in ileal microbiota. Moreover, we identified 1,198 differentially expressed genes (DEGs) in the ileum mucosa, with 957 genes up-regulated in CR and 241 genes up-regulated in FR. In CR, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed the significant enrichment (p < 0.05) of 28 KEGG pathways, most of which were associated with amino acid metabolism. In FR, up-regulated DEGs were mainly enriched in KEGG pathways associated with cellular processes, including apoptosis, necroptosis, and cellular senescence. Spearman correlation analysis of differential microbiota and amino acid metabolism-related DEGs in CR showed a significant positive correlation. Additionally, differential microbiota of FR, Phascolarctobacterium and Sutterella, were positively correlated with FGF10 (p < 0.05) and PIK3R1 (p < 0.01), respectively. In conclusion, there might be differences in ileal amino acid metabolism levels between CR and FR geese, and the observed increase in harmful bacterial species in FR might impact the activity of ileal cells.

19.
Database (Oxford) ; 20242024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38531599

RESUMEN

'Superbugs' have received increasing attention from researchers, such as ESKAPE bacteria (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp.), which directly led to about 1 270 000 death cases in 2019. Recently, phage peptidoglycan hydrolases (PGHs)-derived antimicrobial peptides were proposed as new antibacterial agents against multidrug-resistant bacteria. However, there is still a lack of methods for mining antimicrobial peptides based on phages or phage PGHs. Here, by using a collection of 6809 genomes of ESKAPE isolates and corresponding phages in public databases, based on a unified annotation process of all the genomes, PGHs were systematically identified, from which peptides were mined. As a result, a total of 12 067 248 peptides with high antibacterial activities were respectively determined. A user-friendly tool was developed to predict the phage PGHs-derived antimicrobial peptides from customized genomes, which also allows the calculation of peptide phylogeny, physicochemical properties, and secondary structure. Finally, a user-friendly and intuitive database, ESKtides (http://www.phageonehealth.cn:9000/ESKtides), was designed for data browsing, searching and downloading, which provides a rich peptide library based on ESKAPE prophages and phages. Database URL:  10.1093/database/baae022.


Asunto(s)
Péptidos Antimicrobianos , Bacteriófagos , Bacterias , Klebsiella pneumoniae , Antibacterianos/uso terapéutico
20.
Materials (Basel) ; 17(4)2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38399146

RESUMEN

It is urgent to develop novel technologies to convert carbon dioxide to graphene. In this work, a bubble-mediated approach via a chemical reaction between carbon dioxide gas and magnesium melt to fabricate a few-layer graphene was illustrated. The morphology and defects of graphene can be regulated by manipulating the melt temperature. The preparation of graphene at 720 °C exhibited an excellent quality of surface and graphitization degree. The high-quality few-layer graphene can be grown under the combined effect of carbon dioxide bubbles and in-situ grown MgO. This preparation method possesses the advantages of high efficiency, low cost, and environmental protection, which may provide a new strategy for the recovery and reuse of greenhouse gases.

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