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1.
Plant Cell ; 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38593056

RESUMEN

Little is known about the factors regulating carotenoid biosynthesis in roots. In this study, we characterized DCAR_032551, the candidate gene of the Y locus responsible for the transition of root color from ancestral white to yellow during carrot (Daucus carota) domestication. We show that DCAR_032551 encodes a REPRESSOR OF PHOTOSYNTHETIC GENES (RPGE) protein, named DcRPGE1. DcRPGE1 from wild carrot (DcRPGE1W) is a repressor of carotenoid biosynthesis. Specifically, DcRPGE1W physically interacts with DcAPRR2, an ARABIDOPSIS PSEUDO-RESPONSE REGULATOR2 (APRR2)-like transcription factor. Through this interaction, DcRPGE1W suppresses DcAPRR2-mediated transcriptional activation of the key carotenogenic genes phytoene synthase 1 (DcPSY1), DcPSY2, and lycopene ε-cyclase (DcLCYE), which strongly decreases carotenoid biosynthesis. We also demonstrate that the DcRPGE1W-DcAPRR2 interaction prevents DcAPRR2 from binding to the RGATTY elements in the promoter regions of DcPSY1, DcPSY2, and DcLCYE. Additionally, we identified a mutation in the DcRPGE1 coding region of yellow and orange carrots that leads to the generation of alternatively spliced transcripts encoding truncated DcRPGE1 proteins unable to interact with DcAPRR2, thereby failing to suppress carotenoid biosynthesis. These findings provide insights into the transcriptional regulation of carotenoid biosynthesis and offer potential target genes for enhancing carotenoid accumulation in crop plants.

2.
BMC Genomics ; 24(1): 746, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38057698

RESUMEN

BACKGROUND: Glioblastoma multiforme (GBM) is the most common and lethal primary brain tumor with a poor prognosis. The C-C motif chemokine ligand 2 (CCL2) has shown abnormal expression associated with progression of multiple malignancies, however, its role in predicting the prognosis and immunotherapy response of GBM remains poorly understood. RESULTS: CCL2 was highly expressed in GBM as analyzed by integrating CGGA, GEPIA and UALCAN online platforms, and further verified by histologic examinations, qRT-PCR analysis, and independent GEO datasets. CCL2 could serve as an independent prognostic factor for both the poor overall survival and progression-free survival of GBM patients based on TCGA data, univariate and multivariate cox analyses. Functional enrichment analysis revealed that CCL2 mainly participated in the regulation of chemokine signaling pathway and inflammatory response. Further, CCL2 expression was positively correlated with CD4 T cells, macrophages, neutrophils and myeloid dendritic cells infiltrating GBM as calculated by the TIMER2.0 algorithm. Importantly, the tumor immune dysfunction and exclusion (TIDE) algorithm showed that in CCL2-high GBM group, the expression of CD274, CTLA4, HAVCR2 and other immune checkpoints were significantly increased, and the immune checkpoint blockade (ICB) therapy was accordingly more responsive. CONCLUSIONS: CCL2 can be used as a predictor of prognosis as well as immunotherapy response in GBM, offering potential clinical implications.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/genética , Glioblastoma/terapia , Ligandos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Pronóstico , Quimiocinas , Inmunoterapia , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Quimiocina CCL2/uso terapéutico
3.
Anim Biotechnol ; : 1-9, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37870116

RESUMEN

Fibroblast growth factor 7 (FGF7) is involved in lipid metabolism, which is considered as a candidate gene with close relation with muscle development by eGWAs and RNA-Seq analyses. To date, limited research has been conducted on the relationship between FGF7 gene and growth traits. The main objective of this work was to further investigate the association between novel InDel within FGF7 gene and growth traits in goat. Herein, FGF7 mRNA expression levels were investigated in various Fuqing goat tissues. We found that FGF7 gene was expressed in six adult goat tissues with the highest mRNA levels in adipose tissue. This result suggested that FGF7 gene might play a critical role in fat deposition. We also detected potential polymorphisms in Fuqing, Nubian and Jianyang Daer breeds. A 22-bp InDel polymorphism in FGF7 gene was detected in 396 goats and the three genotypes were designated as II, ID, and DD. Correlation analysis revealed that InDel polymorphism was significantly associated with growth traits (P < 0.05). Goats with genotypes ID and/or II had superior growth traits compared to those with genotype DD. In summary, our findings suggested that the 22-bp InDel within FGF7 gene could act as a molecular marker to improve the growth traits of goats in breeding programs.

4.
Adv Healthc Mater ; 12(29): e2301247, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37440681

RESUMEN

Clinically, arterial injuries are always accompanied with perivascular tissue damage, which may contribute to high failure rate of vein grafts due to intimal hyperplasia and acute thrombosis. In this study, a "perivascular tissue (PVT) deprivation" animal model is constructed to mimic clinical scenarios and identify the contribution of arterial PVT to the success of vein grafts. Proteomics analysis suggests that depriving PVT may exacerbate reactive oxygen species (ROS)-induced endothelial apoptosis by up-regulating inflammation response and oxidative stress. Locally administering metformin on vein grafts through 3D-printed external stent (PGS-PCL) shows antioxidative and anti-inflammatory properties to protect cells from ROS invasion, thereafter decreasing acute thrombosis. Moreover, metformin induce rapid regeneration of perivascular adipose tissue in recipient regions, which improves patency by inhibiting intimal hyperplasia. Proteomics, western blot, and in vitro blocking tests reveal that metformin resists endothelial apoptosis through AMPK/mTOR and NFκB signaling pathways. To conclude, PVT deprivation exacerbates inflammatory response and oxidative stress in vein grafts bridging arterial circulation. Metformin-loaded stent ameliorates "PVT damage" related vein graft failure, and enhances patency of through resisting endothelial apoptosis and regenerating arterial PVAT, offering a promising avenue to improve the success of vein grafts in clinic.


Asunto(s)
Metformina , Trombosis , Animales , Hiperplasia , Antioxidantes/farmacología , Especies Reactivas de Oxígeno , Stents
5.
PLoS One ; 18(3): e0282537, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36862742

RESUMEN

The spatial layout of the coastal forts defense system of the Ming Dynasty of China has been studied in a relatively comprehensive way. Nonetheless, ancient defense mechanisms have not been fully revealed. Previous studies have focused more on the macro and meso levels. Studies into its microscopic construction mechanism need to be enhanced. This research attempts to quantify and validate the rationality of the ancient microscopic defense mechanism, using the ancient defense mechanism of Pu Zhuang Suo-Fort in Zhejiang Province as an instance. This study concentrates on the distribution of firepower strength beyond the walls of coastal defense forts, as well as the effect of wall height on firepower defense capabilities. There is a specific firepower attenuation area near the walls due to the firing blind area in the coastal forts defense system. And the construction of the moat plays an additive role in its defensive capability. Meanwhile, the height of the fort wall will also affect the range of the firing blind zone under Yangmacheng. In theory, there is a reasonable height range of the wall and a proper position of the moat. This height range can meet both good economy and defensive capabilities. In turn, the position of the moats and the height of the walls can verify the rationality of the construction mechanism of the coastal forts' defense system.

6.
Micromachines (Basel) ; 14(3)2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36984991

RESUMEN

Crystallization often occurs in the processing of amorphous alloys, causing the materials lose their excellent properties. The study adopts chemical mechanical polishing of amorphous alloys, presenting the effect of the rotational speed of the polishing turntable, size of abrasive, polishing pressure, and oxidant concentration. The Taguchi method is used to find the best processing parameters, and AFM is used to characterize the machined material surface. At the same time, XPS is used to detect the change of oxide film composition with the addition of oxidant. The results indicate the optimum process parameters: rotational speed of the polishing turntable is 75 r/min, polishing pressure is 28.3 kPa, the size of abrasive is 0.5 µm, and the size of abrasive is a significant factor affecting surface roughness Sa. In addition, as the size of abrasive increases, the material removal rate increases while the surface roughness Sa increases. At pH 10, with an abrasive particle size of 0.5 µm, as the H2O2 concentration increases, the MRR first rapidly decreases at 0.21 wt.% H2O2, and then gradually increases, while the Sa decreases. Furthermore, with the addition of oxidant, the main composition of the surface oxide film changes from oxide to hydroxide, and the contents of Zr4+ and Cu0/Cu1+ elements increase. The findings can provide a feasible chemical mechanical polishing process for zirconium-based amorphous alloys to obtain a satisfactory polishing effect.

7.
Micromachines (Basel) ; 14(1)2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36677261

RESUMEN

In this study, in order to improve and restore the performance of the polishing pads and reduce the cost of chemical mechanical polishing, three types of material polishing pads, namely, polyurethane, damping cloth, and non-woven fabric, were selected for the experiment. Accordingly, each polishing pad was set up with diamond conditioner and high-pressure micro-jet (HPMJ) conditioning control experiments. Subsequently, the fluctuation ranges of the material removal rate on the three polishing pads were 2.73-3.75 µm/h, 1.38-1.99 µm/h, and 2.36-4.32 µm/h, respectively under the HPMJ conditioning method, while the fluctuation ranges of the material removal rate on the three polishing pads were 1.80-4.14 µm/h, 1.02-2.09 µm/h, and 1.78-5.88 µm/h under the diamond conditioning method. Comparing the polishing pad morphologies under SEM, we observed that the surface of the polishing pad after HPMJ conditioning was relatively clean, and the hole structure was not blocked. Contrastingly, there remained numerous abrasive particles on the surface after the conventional diamond conditioning and the hole structure was blocked. Thus, the HPMJ conditioning technology is better than the traditional diamond conditioning technology. Subsequently, the polishing pad after HPMJ conditioning has a longer service life and a more stable material removal rate than that after traditional diamond conditioning.

8.
Front Pharmacol ; 13: 1007279, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36339598

RESUMEN

Melanoma, the most aggressive and deadliest form of skin cancer, has attracted increased attention due to its increasing incidence worldwide. The Cortex Mori (CM) has long been used as a classical traditional Chinese medicine (TCM) to treat various diseases, including cancer. The bioactive components and underlying mechanisms, however, remain largely unknown. The current study aims to investigate the anti-melanoma effects of CM and potential mechanisms through combined network pharmacology and bioinformatic analyses, and validated by in vitro and in vivo experiments. We report here that CM has anti-melanoma activity both in vitro and in vivo. Furthermore, 25 bioactive compounds in CM were found to share 142 melanoma targets, and network pharmacology and enrichment analyses suggested that CM inhibits melanoma through multiple biological processes and signaling pathways, particularly the PI3K-AKT signaling inhibition and activation of apoptotic pathways, which were further confirmed by biochemical and histological examinations. Finally, partial CM-derived bioactive compounds were found to show anti-melanoma effects, validating the anti-melanoma potential of bioactive ingredients of CM. Taken together, these results reveal bioactive components and mechanisms of CM in inhibiting melanoma, providing them as potential anti-cancer natural products for the treatment of melanoma.

9.
Sci Adv ; 8(28): eabn1958, 2022 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-35857526

RESUMEN

Matching material degradation with host remodeling, including endothelialization and muscular remodeling, is important to vascular regeneration. We fabricated 3D PGS-PCL vascular grafts, which presented tunable polymer components, porosity, mechanical strength, and degrading rate. Furthermore, highly porous structures enabled 3D patterning of conjugated heparin-binding peptide, dimeric thymosin ß4 (DTß4), which played key roles in antiplatelets, fibrinogenesis inhibition, and recruiting circulating progenitor cells, thereafter contributed to high patency rate, and unprecedentedly acquired carotid arterial regeneration in rabbit model. Through single-cell RNA sequencing analysis and cell tracing studies, a subset of endothelial progenitor cells, myeloid-derived CD93+/CD34+ cells, was identified as the main contributor to final endothelium regeneration. To conclude, DTß4-inspired porous 3DVGs present adjustable physical properties, superior anticoagulating, and re-endothelializing potentials, which leads to the regeneration of small-caliber artery, thus offering a promising tool for vessel replacement in clinical applications.


Asunto(s)
Injerto Vascular , Animales , Prótesis Vascular , Endotelio Vascular/fisiología , Polímeros , Porosidad , Conejos
10.
Environ Sci Pollut Res Int ; 29(48): 73401-73413, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35619015

RESUMEN

Concentrations, composition profiles, sources, and health risks of 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs) in urban soils from 23 cities across China based on metadata collected from previous studies between 2005 and 2021 were investigated. ΣPAH concentrations in urban soils from 23 cities across China ranged from 0.1231 to 17.2000 mg/kg (mean = 2.7171 ± 3.8276 mg/kg). Overall PAH contamination in urban soils across China was moderate compared to that in global cities. Based on energy consumption and climate conditions, the spatial distributions of mean ΣPAH concentrations in Northeast China were highest, followed by those in North China, West China, East China, and South China. Individual PAH composition profiles decreased in the order: 4-ring PAHs (41.36%) > 5-ring PAHs (21.77%) > 3-ring PAHs (18.53%) > 6-ring PAHs (14.00%) > 2-ring PAHs (2.27%). Diagnostic ratios and positive matrix factorization (PMF) revealed that PAHs in urban soils were mainly derived from fossil fuel combustion (from coal, natural gas, and biomass), especially in North, Northeast, and East China, with smaller contributions from petrogenic sources. Health risk assessment results suggest that although there are potential cancer risks from PAHs, risks were acceptable. Toxic equivalent concentration (TEQ) and the corresponding oral cancer slope factor (CFS0) contributed most to the uncertainty of total risks. This study will help develop strategies to reduce PAH risk management in urban soils in China.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Contaminantes del Suelo , China , Ciudades , Carbón Mineral/análisis , Monitoreo del Ambiente/métodos , Gas Natural , Hidrocarburos Policíclicos Aromáticos/análisis , Medición de Riesgo , Suelo , Contaminantes del Suelo/análisis
11.
Cell Death Discov ; 8(1): 174, 2022 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-35393406

RESUMEN

Oxygenase-catalyzed reduction and activation of oxygen molecules and the incorporation of oxygen atoms into organic molecules are undoubtedly necessary in the process of tumor development, and it is also one of the research hotspots in recent years. MOXD1 belongs to the copper-dependent monooxygenase family. The expression of MOXD1 is one of the characteristics of early tumor development. However, it is not understandable that the biological function and molecular mechanism of MOXD1 in Glioblastoma (GBM). In this study, high MOXD1 expression is strongly associated with poor survival of the patient with GBM. Moreover. MOXD1 knockdown can inhibit cell viability, proliferation, migration, invasion, and tumorigenesis of GBM cells. This is also proven for the first time that MOXD1 can bind to ß3GnT2 and affect the glycosylation modification of some proteins. In addition, knockdown of MOXD1 induces endoplasmic reticulum (ER) stress and triggers the ER-mitochondrial apoptosis pathway. Taken together, these results reveal that MOXD1 is involved in the occurrence and development of GBM, and also provide a new strategy for targeted therapy.

12.
Bioact Mater ; 11: 283-299, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34977432

RESUMEN

Declined regenerative potential and aggravated inflammation upon aging create an inappropriate environment for arterial regeneration. Macrophages are one of vital effector cells in the immune microenvironment, especially during biomaterials mediated repairing process. Here, we revealed that the macrophage autophagy decreased with aging, which led to aggravated inflammation, thereby causing poor vascular remodeling of artificial grafts in aging body. Through loading the autophagy-targeted drugs, rapamycin and 3-MA (3-methyladenine), in PCL (polycaprolactone) sheath of the PGS (poly glycerol sebacate) - PCL vascular graft, the essential role of macrophage autophagy was confirmed in regulating macrophage polarization and biomaterial degradation. Moreover, the utilization of rapamycin promoted anti-inflammatory polarization of macrophage by activating autophagy, which further promoted myogenic differentiation of vascular progenitor cells and accelerated endothelialization. Our study elucidated the contribution of pharmacological manipulation of macrophage autophagy in promoting regeneration of small caliber artery, which may pave a new avenue for clinical translation of vascular grafts in aging body.

13.
Acta Biomater ; 140: 659-673, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-34902618

RESUMEN

The improvement of cell survival in cartilage tissue engineering remains a challenge, especially for large-sized, specifically shaped cartilage grafts used in reconstructing craniofacial defects. In this study, we found that bone marrow mesenchymal stem cells (BMSCs) pre-conditioned in a starving environment enhanced the anti-apoptosis potential of co-transplanted chondrocytes, which significantly enhanced their survival rates before host nutrition was resumed. Further examination revealed that extracellular vesicles (EVs) derived from starving BMSCs played essential roles in ameliorating apoptosis and regulating autophagy of chondrocytes, thereby enhancing the survival of cultured chondrocytes. In vivo studies demonstrated that EVs derived from starving BMSCs significantly improved the survival of chondrocyte bricks, which confirmed the effects of nasal augmentation. These pre-treated chondrocyte bricks showed continuous cartilage growth in vivo and acquired chondrogenesis comparable to that following the chondrocyte-BMSC co-transplantation approach. This study provided new insights on how BMSC-derived EVs improved cartilage reconstruction in the craniofacial regions and offered a new approach for regenerating cartilaginous organs based on cell macroaggregates. STATEMENT OF SIGNIFICANCE: The use of extracellular vesicles (EVs) of mesenchymal stem cells has been considered as a promising approach in cartilage tissue engineering. In the present study, for the first time, we investigated the protective effect of EVs secreted by starving bone marrow mesenchymal stem cells (BMSCs) on chondrocytes in vitro and in vivo. The results demonstrated that EVs secreted by starving BMSCs inhibited chondrocyte apoptosis and chondrocyte autophagy through many microRNAs, thereby improving the survival of grafts. Transcriptomic analysis revealed the potential mechanisms of this protective effect.


Asunto(s)
Vesículas Extracelulares , Células Madre Mesenquimatosas , Apoptosis , Cartílago , Diferenciación Celular , Células Cultivadas , Condrocitos/trasplante , Condrogénesis/fisiología
14.
Environ Geochem Health ; 44(10): 3639-3654, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34687406

RESUMEN

Characteristics, profile composition, ecological and human health risk of polycyclic aromatic hydrocarbons in surface dust collected from Shenyang city, China, were investigated. Concentrations of 16 USEPA priority PAHs ranged between 371.57 and 3300.04 µg/kg (mean 1244.76 ± 715.25 µg/kg). Fluoranthene was the most abundant individual PAHs, followed by pyrene, and high molecular weight PAHs, more than three times of low molecular weight PAHs, were the predominant components. Profiles of PAHs showed that 4-ring PAHs were dominant, followed by 3-ring and 5-ring PAHs, and indicated that combustion sources accounted for the most PAHs. Results of diagnostic ratios and positive matrix factorization all suggested that pyrogenic sources were the most important source of PAHs in urban dust, followed by natural gas combustion and petrogenic sources, and traffic emissions would play an increasingly critical role with the increasing of vehicles. Health risk assessment suggested children were the most vulnerable to PAHs compared to adolescents and adults. Ingestion was the most important exposure pathway. The total lifetime cancer risk of 43.33% of sampling sites was higher than 10-6, but the TLCR at all sites was much lower than the highest acceptable risk established by USEPA (10-4).


Asunto(s)
Polvo , Hidrocarburos Policíclicos Aromáticos , Adolescente , Adulto , Niño , China , Polvo/análisis , Monitoreo del Ambiente/métodos , Humanos , Gas Natural , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/toxicidad , Pirenos , Medición de Riesgo
15.
Biomaterials ; 276: 120998, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34237507

RESUMEN

Crosstalk between bone marrow mesenchymal stem cells (BMSCs) and macrophages plays vital role in bone healing. By investigating the mechanism of collagen membrane-guided bone regeneration, we found compact structure and rapid membrane degradation compromised the duration of M2 macrophages influx, which restricts the recruitment of BMSCs that is essential for bone healing. To tackle this issue, a biodegrading elastomeric compound consisting of poly(glycerol sebacate) (PGS) and polycaprolactone (PCL) was fabricated into hierarchically porous membrane. The rational design of 3D microstructure enabled sufficient polydopamine (PDA) coating. Without any addition of growth factors, the 3D-patterned PDA membrane enables early and durable influx of M2 macrophages, which in turn promotes BMSCs recruitment and osteogenic differentiation. Furthermore, 4D-morphing of the membrane fully regenerates the dome shaped calvarial bone as well as arc-shape bone in peri-implant alveolar defect without filling xenogenous substitute. This study revealed the superiority of 3D printed microstructures in immunomodulatory materials. The availability of 4D-morphing for PGS/PCL construct expanded their advantages in reconstructing craniofacial bone.


Asunto(s)
Bivalvos , Osteogénesis , Animales , Regeneración Ósea , Diferenciación Celular , Elastómeros , Macrófagos , Andamios del Tejido
16.
Environ Sci Pollut Res Int ; 27(33): 41515-41523, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32691315

RESUMEN

This paper proposes a quantitative method to optimize the existing river monitoring network based on a modified approaching degree model, T test, and Euclidean distance. In this study, the Liaohe River located in Liaoning province, China, was taken as a research object. Samples were collected from 8 sampling sites throughout the monitoring network, and water quality parameters were analyzed every 2 months from January 2009 to December 2010. The results show that the average concentrations of the ammonia nitrogen (NH4+-N) and chemical oxygen demand (COD) were beyond grade III of the Environmental Quality Standards for Surface Water of China (GB3838-2002), and they were the main water quality parameters. After optimization, the number of monitoring sections along the Liaohe River was reduced to five from the original eight, thus saving 37.5% of the monitoring cost; meanwhile, there is no significant difference between the un-optimized and optimized monitoring networks, and the optimized monitoring network remains to be able to perform as good as the original one. In addition, the total data attainment rate was improved greatly, and the duplicate setting degree of monitoring points decreased significantly compared with other optimal methods. The optimized monitoring network proves to be more efficient, reasonable, and economically feasible, so this quantitative method can help optimize the changing orderly river monitoring networks.


Asunto(s)
Ríos , Contaminantes Químicos del Agua , Análisis de la Demanda Biológica de Oxígeno , China , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Calidad del Agua
17.
Sci Total Environ ; 669: 120-128, 2019 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-30878920

RESUMEN

Environmental processes of nanoplastics in heterogeneous natural groundwater systems remain unclear. In this study, the control of particle size and surface functional groups on the fate and transport of nanoplastics in an organic matter (OM) rich aquifer was explored using batch and column tests. The carboxyl-modified 200 nm (200CNP), carboxyl-modified 50 nm (50CNP), and amino-modified 50 nm (50ANP) polystyrene latex beads were used as surrogates for nanoplastics of contrasting sizes and surface functional groups. Aquifer sand and natural groundwater sampled from an agriculture-impacted shallow sandy aquifer were processed to obtain granule beds with/out surface minerals and groundwater containing different-sized fractions of OM. Results show that particle size controlled the hetero-aggregation rate of nanoplastics with OM and Ca2+: a larger size resulting in a lower reaction rate led to a higher stability of 200CNP than 50CNP and 50ANP. Meanwhile, surface functional groups appeared to affect the affinity of OM and Ca2+ to nanoplastics, i.e. the amino group allowed the adsorption of dissolved OM on the particle but inhibited the adsorption of Ca2+ and suspended OM, while the carboxyl group allowed adsorption of the all. The resulting variable OM coatings formed on the different nanoplastics played a critical role in determining the particle stability and mobility, i.e. the suspended OM increased both the particle stability and mobility while the dissolved OM reduced both. These findings suggest that: 1. Depending on the OM properties, the influence of particle size and surface group on the nanoplastic processes might be secondary to the OM impact; 2. In evaluating the OM impact, not only the OM concentration but also the size and surface physiochemistry of the OM should be characterized. The insight gained is important to predict the concentration evolution pattern of weathered nanoplastics in OM-impacted sandy aquifers.

18.
J Basic Microbiol ; 59(3): 337-347, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30561145

RESUMEN

Microbial community assembly is affected by the trade-off between deterministic and stochastic processes, but the mechanisms underpinning their relative influences remain elusive. This knowledge gap strongly limits our ability to predict the effect of environmental filtering on microbial community structure and function. To improve the understanding of mechanisms underlying community assembly processes, we investigated bacterial community structure and function on a subalpine shady slope and a sunny slope in the Pangquangou National Nature Reserve in North China. By integrating the results of a null model and the RC metric, we inferred that a deterministic process, that is, environmental filtering, drove bacterial community biogeographical patterns. Edaphic factors caused the largest contribution to microbial community structure, followed by vegetation and spatial variables. Among edaphic factors, total carbon (TC) and total nitrogen (TN) were the most important factors as determined by redundancy analysis (RDA). Moreover, network analysis suggested that the status of bacterial community co-occurrence was significantly greater than that of exclusive relationships. Under environmental stress, there was no significant difference in the overall bacterial community structure on the different slopes, while significant differences were observed in relation to community functions. Given this, we inferred that the degrees of response of bacterial community structure and function to varying environments were not consistent. In conclusion, our results contribute to the understanding of deterministic versus stochastic balance in bacterial community assembly and the response mechanisms of community structure and function to environmental heterogeneity.


Asunto(s)
Bacterias/metabolismo , Ambiente , Microbiota , Microbiología del Suelo , Bacterias/clasificación , Bacterias/genética , Biodiversidad , Carbono/metabolismo , China , Modelos Teóricos , Nitrógeno/metabolismo , ARN Ribosómico 16S/genética , Suelo/química , Árboles/crecimiento & desarrollo
19.
Zhonghua Nan Ke Xue ; 16(12): 1098-100, 2010 Dec.
Artículo en Chino | MEDLINE | ID: mdl-21348201

RESUMEN

OBJECTIVE: To study the clinical characteristics and treatment of Fournier's gangrene. METHODS: We retrospectively analyzed the clinical data of 23 cases of Fournier's gangrene, all with flare and pains in the scrotum and penis and different degrees of involvement of the scrotum, penis, perianal area, perineum, inguinal and lower extremities. The patients were treated by early debridement, incision-drainage, anti-infection and hyperbaric oxygen therapy, respectively. Scrotoplasty was performed for 11 of the cases, penile and scrotal dermatoplasty for 7, and penile amputation and urethral fistulation for 2 with penile necrosis. One of the cases underwent suprapubic cystostomy, and another 1 received colostomy. RESULTS: Twenty of the patients were recovered and 3 (1 with diabetes and 1 with AIDS) died after surgery. CONCLUSION: Fournier's gangrene is a fatal disease. Early diagnosis and timely surgical intervention are essential for the management of the disease.


Asunto(s)
Gangrena de Fournier/diagnóstico , Gangrena de Fournier/cirugía , Adulto , Anciano , Gangrena de Fournier/terapia , Humanos , Masculino , Persona de Mediana Edad , Pene/patología , Pene/cirugía , Estudios Retrospectivos , Escroto/patología , Escroto/cirugía
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