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1.
Int J Biol Macromol ; 269(Pt 2): 132058, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38704065

RESUMEN

In clinical practice, tumor-targeting diagnosis and immunotherapy against programmed death ligand 1 (PD-L1) have a significant impact. In this research, a PD-L1-antagonistic affibody dimer (ZPD-L1) was successfully prepared through Escherichia coli expression system, and conjugated with the photosensitizer of ICG via N-hydroxysuccinimide (NHS) ester to develop a novel tumor-targeting agent (ICG-ZPD-L1) for both tumor imaging diagnosis and photothermal-immunotherapy simultaneously. In vitro, ZPD-L1 could specifically bind to PD-L1-positive LLC and MC38 tumor cells, and ICG-ZPD-L1-mediated photothermal therapy (PTT) also showed excellent phototoxicity to these tumor cells. In vivo, ICG-ZPD-L1 selectively enriched into the PD-L1-positive MC38 tumor tissues, and the high-contrast optical imaging of tumors was obtained. ICG-ZPD-L1-mediated PTT exhibited a potent anti-tumor effect in vivo due to its remarkable photothermal properties. Furthermore, ICG-ZPD-L1-mediated PTT significantly induced the immunogenic cell death (ICD) of primary tumors, promoted maturation of dendritic cells (DCs), up-regulated anti-tumor immune response, enhanced immunotherapy, and superiorly inhibited the growth of metastatic tumors. In addition, ICG-ZPD-L1 showed favorable biosafety throughout the brief duration of treatment. In summary, these results suggest that ICG-ZPD-L1 is a multifunctional tumor-targeting drug integrating tumor imaging diagnosis and photothermal-immunotherapy, and has great guiding significance for the diagnosis and treatment of clinical PD-L1-positive tumor patients.


Asunto(s)
Antígeno B7-H1 , Inmunoterapia , Verde de Indocianina , Animales , Antígeno B7-H1/metabolismo , Ratones , Inmunoterapia/métodos , Verde de Indocianina/química , Verde de Indocianina/farmacología , Línea Celular Tumoral , Terapia Fototérmica/métodos , Humanos , Neoplasias/terapia , Neoplasias/diagnóstico por imagen , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/farmacología , Fototerapia/métodos
2.
Nat Commun ; 15(1): 3143, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609359

RESUMEN

Largely removed from anthropogenic delivery of nitrogen (N), Antarctica has notably low levels of nitrogen. Though our understanding of biological sources of ammonia have been elucidated, the microbial drivers of nitrate (NO3-) cycling in coastal Antarctica remains poorly understood. Here, we explore microbial N cycling in coastal Antarctica, unraveling the biological origin of NO3- via oxygen isotopes in soil and lake sediment, and through the reconstruction of 1968 metagenome-assembled genomes from 29 microbial phyla. Our analysis reveals the metabolic potential for microbial N2 fixation, nitrification, and denitrification, but not for anaerobic ammonium oxidation, signifying a unique microbial N-cycling dynamic. We identify the predominance of complete ammonia oxidizing (comammox) Nitrospira, capable of performing the entire nitrification process. Their adaptive strategies to the Antarctic environment likely include synthesis of trehalose for cold stress, high substrate affinity for resource utilization, and alternate metabolic pathways for nutrient-scarce conditions. We confirm the significant role of comammox Nitrospira in the autotrophic, nitrification process via 13C-DNA-based stable isotope probing. This research highlights the crucial contribution of nitrification to the N budget in coastal Antarctica, identifying comammox Nitrospira clade B as a nitrification driver.


Asunto(s)
Amoníaco , Nitrificación , Regiones Antárticas , Respuesta al Choque por Frío , Nitrógeno
3.
Chemosphere ; 344: 140377, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37806323

RESUMEN

Quantification of polycyclic aromatic hydrocarbons (PAHs) in contaminated soil and identification of potential PAH degraders are essential for comprehending their environmental fate and conducting bioremediation. However, the microbial population responsible for the breakdown of phenanthrene (PHE) in polluted soil environments is frequently disregarded. In this study, via DNA-stable-isotope probing (DNA-SIP), we found that soil microbiota likely plays a crucial part in the PHE degradation. The PHE removal rates were 98% and 99%, in 13C-PHE and 12C-PHE microcosmic incubations, respectively. 13CO2 was produced along with the degradation of 13C-PHE. According to the analysis of 16S rRNA gene, there was a relatively higher presence of unidentified bacteria in the 'heavy' DNA fractions treated with 13C-PHE. Genus of Enterobacteriales, Acidobacteria, Alphaproteobacteria, Paenibacillaceae, Flavobacteriia, Chloroflexi, Cyanobacteria, Caldilineae, Latescibacteria, Armatimonadetes and Blastocatellia were succseesfully labeled during the degradation of 13C-PHE, indicating their capacity of utilizing PHE. Co-occurrence network of 13C-heavy fractions exhibited greater complexity compared with that of 12C-heavy fractions, revealling an enhancement of bacterial interspecies interactions. Collectivley, this study eluidated the soil microbes involed in the PHE degradation and offered fresh perspectives on the community pattern of potential PHE degrading bacteria.


Asunto(s)
Fenantrenos , Hidrocarburos Policíclicos Aromáticos , Contaminantes del Suelo , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/metabolismo , Fenantrenos/metabolismo , Hidrocarburos Policíclicos Aromáticos/metabolismo , Bacterias/metabolismo , Isótopos , Acidobacteria , Biodegradación Ambiental , ADN/metabolismo , Suelo , Microbiología del Suelo , Contaminantes del Suelo/metabolismo
4.
Sci Total Environ ; 904: 167333, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37748616

RESUMEN

Complete ammonia oxidizer (comammox Nitrospira), catalyze complete nitrification process in a single organism, are frequently detected in groundwater ecosystem. However, the ecological niches and environmental driving factors of comammox Nitrospira in urban groundwater are largely unknown. Here we investigated the communities of ammonia oxidizers in urban groundwater located in Shanghai city, China. Quantitative analysis demonstrated the dominance of comammox Nitrospira over classical ammonia oxidizers (ammonia-oxidizing archaea and bacteria, AOA and AOB). Phylogenetic analysis showed clades B and A2 comprise the majority of comammox Nitrospira groups. Temperature was one of the most vital factors affecting comammox Nitrospira community. Furthermore, clade A comammox Nitrospira can be enriched by urea substrate, which was in line with the ability of utilizing urea by the pure clade A comammox culture Nitrospira inopinata. In addition, we observed that relatively low temperature (<20 °C) and high copper levels (>0.04 mg L-1) can stimulate the growth of comammox Nitrospira. Overall, this study revealed the presence, diversity and physiological preferences of comammox Nitrospira in urban groundwater nitrification, shedding insights on the ecological roles of comammox Nitrospira in subsurface environment.


Asunto(s)
Amoníaco , Agua Subterránea , Filogenia , Ecosistema , Oxidación-Reducción , China , Bacterias , Archaea , Nitrificación , Agua Subterránea/microbiología , Urea
5.
J Ethnopharmacol ; 314: 116547, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37178983

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Traditional Chinese medicine (TCM) theory believes kidney deficiency is the root cause of chronic refractory asthma with pathological changes of airway remodeling. Our previous experiments confirmed that the combination of Epimedii Folium and Ligustri Lucidi Fructus (ELL) with the effect of nourishing Yin and Yang of the kidney could improve the pathological changes of airway remodeling in asthmatic rats, but the specific mechanism remains unclear. AIM OF THE STUDY: This research was designed to reveal the synergy of ELL and dexamethasone (Dex) in the proliferation, apoptosis, and autophagy of airway smooth muscle cells (ASMCs). MATERIALS AND METHODS: Primary cultures of ASMCs from rats were prepared and induced with histamine (Hist), Z-DEVD-FMK (ZDF), rapamycin (Rap), or 3-Methyladenine (3-MA) at generation 3-7 for 24 or 48 h. Subsequently, the cells were treated with Dex, ELL, and ELL&Dex for 24 or 48 h. The effect of various concentrations of inducers and drugs on cell viability was detected by Methyl Thiazolyl Tetrazolium (MTT) assay, cell proliferation was tested using immunocytochemistry (ICC) by detecting Ki67 protein, cell apoptosis was measured by Annexin V-FITC/PI assay and Hoechst nuclear staining, cell ultrastructure was observed by transmission electron microscopy (TEM), and immunofluorescence (IF), Western blot (WB) combined with quantitative real-time PCR (qPCR) were used for measuring autophagy and apoptosis-related genes including protein 53 (P53), cysteinyl aspartate-specific proteinase (Caspase)-3, microtubule-associated protein 1 light chain 3 (LC3), Beclin-1, mammalian target of rapamycin (mTOR) and p-mTOR. RESULTS: In ASMCs, Hist and ZDF promoted cell proliferation, significantly decreased Caspase-3 protein expression, and up-regulated Beclin-1 levels; Dex alone and in combination with ELL promoted Beclin-1, Caspase-3, and P53 expression, enhancing autophagy activity and apoptosis in Hist and ZDF-induced AMSCs. In contrast, Rap inhibited cell viability, increased Caspase-3, P53, Beclin-1, and LC3-II/I and decreased the levels of mTOR and p-mTOR with promoting apoptosis and autophagy; ELL or ELL&Dex reduced P53, Beclin-1, and LC3-II/I to down-regulate apoptosis and the excessive autophagic state of ASMCs induced by Rap. In the 3-MA model, cell viability and autophagy were reduced; ELL&Dex significantly upgraded the expression of Beclin-1, P53, and Caspase-3 and promoted apoptosis and autophagy of ASMCs. CONCLUSIONS: These results suggest that ELL combined with Dex may regulate the proliferation of ASMCs by promoting apoptosis and autophagy and be a potential medicine for the treatment of asthma.


Asunto(s)
Asma , Ligustrum , Ratas , Animales , Beclina-1/metabolismo , Remodelación de las Vías Aéreas (Respiratorias) , Caspasa 3/metabolismo , Proteína p53 Supresora de Tumor , Asma/tratamiento farmacológico , Apoptosis , Serina-Treonina Quinasas TOR/metabolismo , Miocitos del Músculo Liso/metabolismo , Proliferación Celular , Dexametasona/farmacología , Dexametasona/uso terapéutico , Autofagia , Mamíferos/metabolismo
6.
Nanomaterials (Basel) ; 13(6)2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36985868

RESUMEN

Delicate design and precise manipulation of electrode morphology has always been crucial in electrochemistry. Generally, porous morphology has been preferred due to the fast kinetic transport characteristics of cations. Nevertheless, more refined design details such as the granularity uniformity that usually goes along with the porosity regulation of film electrodes should be taken into consideration, especially in long-term cation insertion and extraction. Here, inorganic electrochromism as a special member of the electrochemical family and WO3 films as the most mature electrochromic electrode material were chosen as the research background. Two kinds of WO3 films were prepared by magnetron sputtering, one with a relatively loose morphology accompanied by nonuniform granularity and one with a compact morphology along with uniform particle size distribution, respectively. Electrochemical performances and cyclic stability of the two film electrodes were then traced and systematically compared. In the beginning, except for faster kinetic transport characters of the 50 W-deposited WO3 film, the two electrodes showed equivalent optical and electrochemical performances. However, after 5000 CV cycles, the 50 W-deposited WO3 film electrode cracked seriously. Strong stress distribution centered among boundaries of the nonuniform particle clusters together with the weak bonding among particles induced the mechanical damage. This discovery provides a more solid background for further delicate film electrode design.

7.
J Environ Manage ; 336: 117602, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-36967687

RESUMEN

Biochar has been shown to affect the nitrogen (N) cycle in soil, however, it is unknown how this occurs. Therefore, we used metabolomics, high-throughput sequencing, and quantitative PCR to explore biochar and nitrogen fertilizer effects on the mitigation mechanisms of adverse environments in acidic soil. In the current research, we used acidic soil and maize straw biochar (pyrolyzed at 400 °C with limited oxygen). Three maize straw biochar levels (B1; 0t ha-1, B2; 45 t ha-1, and B3; 90 t ha-1) along with three N fertilizer (urea) levels (N1; 0 kg ha-1, N2; 225 kg ha-1 mg kg-1, and N3; 450 kg ha-1 mg kg-1) were employed in a sixty-day pot experiment. We found that the formation of NH+ 4-N was faster at 0-10 days, while the formation of NO- 3-N occurred at 20-35 days. Furthermore, the combined application of biochar and N fertilizer most effectively boosted soil inorganic N contents compared to biochar and N fertilizer treatments alone. The B3 treatment increased the total N and total inorganic N by 0.2-24.2% and 55.2-91.7%, respectively. Soil microorganism, N fixation, and nitrification capabilities increased with biochar and N fertilizer addition in terms of N-cycling-functional genes. Biochar-N fertilizer had a greater impact on the soil bacterial community and their diversity and richness. Metabolomics revealed 756 distinct metabolites, including 8 substantially upregulated metabolites and 21 significantly downregulated metabolites. A significant amount of lipids and organic acids were formed by biochar-N fertilizer treatments. Thus, biochar and N fertilizer triggered soil metabolism by affecting bacterial community structure, and N-cycling of the soil micro-ecological environment.


Asunto(s)
Microbiota , Suelo , Suelo/química , Fertilizantes/análisis , Carbón Orgánico/química , Ciclo del Nitrógeno , Microbiología del Suelo , Nitrógeno/análisis
8.
Oxid Med Cell Longev ; 2023: 7212642, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36760348

RESUMEN

Osteoblast (OB) and osteoclast (OC) play important roles in bone formation and bone resorption, which can communicate with each other through cytokine paracrine. Previous studies have confirmed that Epimedii Folium (EF) and Ligustri Lucidi Fructus (LLF) used alone or in combination can treat osteoporosis (OP) through regulating bone remodeling, but the effects of EF and LLF on osteoblastogenesis, osteoclastogenesis, and OB-OC communication are unclear. In this study, we investigated the direct and indirect effects of EF and LLF on OBs and OCs via monoculture and coculture (transwell) models of OBs and OCs. We found that the combination of EF and LLF (EF&LLF) could promote osteoblastogenesis and inhibit osteoclastogenesis directly and indirectly. In order to study the mechanisms of EF&LLF on indirectly regulating osteoblastogenesis and osteoclastogenesis, we detected the expression of cytokines by which OBs and OCs could communicate with each other. We found that EF&LLF could downregulate the expression of RANKL and M-CSF and the protein ratio of RANKL/OPG of OBs and Atp6v0d2 expression of OCs and upregulate the expression of OPG and TGF-ß1 of OBs and the expression of TGF-ß1, BMP-2, and IGF-1 of OCs, indicating that EF&LLF could regulate cytokine expressions of OBs/OCs to affect OB-OC communication. In addition, EF&LLF had a better effect on regulating cytokines of OBs and OCs than EF or LLF in single use. This study suggested that EF&LLF exhibited the effects of promoting osteoblastogenesis and inhibiting osteoclastogenesis via acting on OB-OC communication and provided some scientific evidences for EF&LLF against OP.


Asunto(s)
Ligustrum , Osteoporosis , Diferenciación Celular , Citocinas/metabolismo , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteogénesis , Osteoporosis/metabolismo , Ligando RANK/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Comunicación Celular
9.
J Hazard Mater ; 445: 130558, 2023 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-36495641

RESUMEN

Benzimidazole fungicides are frequently detected in aquatic environments and pose a serious health risk. Here, we investigated the metabolic capacity of the recently discovered complete ammonia-oxidizing (comammox) Nitrospira inopinata and kreftii to transform a representative set of benzimidazole fungicides (i.e., benzimidazole, albendazole, carbendazim, fuberidazole, and thiabendazole). Ammonia-oxidizing bacteria and archaea, as well as the canonical nitrite-oxidizing Nitrospira exhibited no or minor biotransformation activity towards all the five benzimidazole fungicides. In contrast, the investigated comammox bacteria actively transformed all the five benzimidazole fungicides, except for thiabendazole. The identified transformation products indicated hydroxylation, S-oxidation, and glycosylation as the major biotransformation pathways of benzimidazole fungicides. We speculated that these reactions were catalyzed by comammox-specific ammonia monooxygenase, cytochrome P450 monooxygenases, and glycosylases, respectively. Interestingly, the exposure to albendazole enhanced the expression of the antibiotic resistance gene acrB of Nitrospira inopinata, suggesting that some benzimidazole fungicides could act as environmental stressors that trigger cellular defense mechanisms. Altogether, this study demonstrated the distinct substrate specificity of comammox bacteria towards benzimidazole fungicides and implies their significant roles in the biotransformation of these fungicides in nitrifying environments.


Asunto(s)
Fungicidas Industriales , Fungicidas Industriales/toxicidad , Fungicidas Industriales/metabolismo , Proteómica , Amoníaco/metabolismo , Albendazol , Tiabendazol , Nitrificación , Bacterias/metabolismo , Archaea/metabolismo , Biotransformación , Oxidación-Reducción , Bencimidazoles/toxicidad , Bencimidazoles/metabolismo , Filogenia
10.
World Neurosurg ; 166: e460-e468, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35840094

RESUMEN

OBJECTIVE: A Stereotaxic Atlas of the Human Lumbar-Sacral Spinal Cord has been created to provide an anatomical basis for radiologic and ultrasonic imaging and electrophysiological examination, which are used to target the placement of lumbar-sacral epidural stimulating electrodes and cellular transplantation in order to restore movement in individuals with sustained spinal cord injury or a degenerative disorder of the spinal cord. Through the availability of an atlas that exhibits axial images of the cytoarchitecture of each cord segment with a stereotaxic millimeter grid of dorsal-ventral depth from the midline dorsal surface of the cord and right-left distances from the midline of the cord, neuromodulation, and cellular therapy would undoubtedly be made not only more precise but also safer for patients. METHODS: The atlas is based upon dimension measurements and subsequent serial sectioning, staining and high-resolution digital imaging of the lumbar-sacral enlargement of 20 adult human spinal cords. RESULTS: Nissl stained cross-sections from cord segments L1-S3 illustrate the cytoarchitecture and stereotactic coordinates. CONCLUSIONS: The atlas provides an anatomical basis for radiologic and physiologic confirmation of target localization in the lumbar-sacral spinal cord.


Asunto(s)
Sacro , Traumatismos de la Médula Espinal , Adulto , Humanos , Región Lumbosacra , Región Sacrococcígea , Sacro/diagnóstico por imagen , Médula Espinal/diagnóstico por imagen , Médula Espinal/fisiología
11.
Int J Biol Markers ; 37(3): 249-259, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35730164

RESUMEN

Overall survival of non-small cell lung cancer (NSCLC) patients remains disappointingly low. The estrogen receptor (ER) was considered a promising therapeutic target for NSCLC. Numerous studies have linked expression of ERß to lung cancer outcome. However, results are conflicting regarding the association of ERß with surviving lung cancer. The aim of this meta-analysis was to evaluate the prognostic aspect of ERß expression on survival among NSCLC patients. We performed a final analysis of prognostic value of overexpression ERß on 3500 patients from 18 evaluable studies (from January 1, 2000 to May 1, 2021). The reference category is specified as low ERß expression levels. Summarized hazard ratios were calculated. Our study showed that the pooled hazard ratios of ERß overexpression for overall survival in NSCLC was 0.81 (95% confidence interval (CI): 0.64-1.02, P = 0.07) by univariate analysis and 1.06 (95% CI: 0.83-1.36, P = 0.63) by multivariate analysis. Pooled hazard ratio by univariate analysis in Asian studies was 0.73 (95%CI: 0.59-0.89, P = 0.002). Pooled hazard ratio by univariate analysis was 0.75 (95% CI: 0.61-0.93, P = 0.009) from seven studies reported for nuclear ERß. No significant results were found in subgroups by multivariate analysis. No significant results were found in studies outside Asia or in studies reported for cytoplasmic ERß. Our results suggested that expression of ERß might not be a direct prognostic factor for NSCLC patients. More detailed prospective studies are needed to identify direct prognostic factors in these patients.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Receptor beta de Estrógeno/genética , Receptor beta de Estrógeno/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Pronóstico , Modelos de Riesgos Proporcionales
12.
Water Res ; 216: 118381, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35381430

RESUMEN

Dark carbon fixation (DCF) contributes approximately 0.77 Pg C y-1 to oceanic primary production and the global carbon budget. It is estimated that nearly half of the DCF in marine sediments occurs in estuarine and coastal regions, but the environmental factors controlling DCF and the microorganisms responsible for its production remain under exploration. In this study, we investigated DCF rates and the active chemoautotrophic microorganisms in intertidal sediments of the Yangtze Estuary, using 14C-labeling and DNA-stable isotope probing (DNA-SIP) techniques. The measured DCF rates ranged from 0.27 to 3.37 mmol C m-2 day-1 in intertidal surface sediments. The rates of DCF were closely related to sediment sulfide content, demonstrating that the availability of reductive substrates may be the dominant factor controlling DCF in the intertidal sediments. A significant positive correlation was also observed between the DCF rates and abundance of the cbbM gene. DNA-stable isotope probing (DNA-SIP) results further confirmed that cbbM-harboring bacteria, rather than cbbL-harboring bacteria, played a dominant role in DCF in intertidal sediments. Phylogenetic analysis showed that the predominant cbbM-harboring bacteria were affiliated with Burkholderia, including Sulfuricella denitrificans, Sulfuriferula, Acidihalobacter, Thiobacillus, and Sulfurivermis fontis. Moreover, metagenome analyses indicated that most of the potential dark-carbon-fixing bacteria detected in intertidal sediments also harbor genes for sulfur oxidation, denitrification, or dissimilatory nitrate reduction to ammonium (DNRA), indicating that these chemoautotrophic microorganisms may play important roles in coupled carbon, nitrogen, and sulfur cycles. These results shed light on the ecological importance and the underlying mechanisms of the DCF process driven by chemoautotrophic microorganisms in intertidal wetlands.


Asunto(s)
Bacterias , Ciclo del Carbono , Bacterias/genética , Carbono , ADN , Sedimentos Geológicos/química , Nitratos/análisis , Nitrógeno , Filogenia , Azufre
13.
Front Microbiol ; 12: 731921, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34512610

RESUMEN

[This corrects the article DOI: 10.3389/fmicb.2020.589268.].

14.
Sci Total Environ ; 795: 148768, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34247082

RESUMEN

The recent discovery of complete ammonia oxidizers (comammox), which convert ammonia to nitrate in a single organism, revolutionized the conventional understanding that two types of nitrifying microorganisms have to be involved in the nitrification process for more than 100 years. However, how different types of nitrifiers in response to salinity change remains largely unclear. This study not only investigated nitrifier community (including ammonia-oxidizing archaea (AOA), ammonia-oxidizing bacteria (AOB), comammox and nitrite-oxidizing Nitrospira) in the Nanliu estuary to find the ecological relationship between salinity and functional communities and also studied the physiology of a typical comammox Nitrospira inopinata in response to a salinity gradient. Based on sequences retrieved with four sets of functional gene primes, comammox Nitrospira was in general, mainly composed of clade A, with a clear separation of clade A1 subgroup in all samples and clade A2 subgroup in low salinity ones. As expected, group I.1b and group I.1a AOA dominated the AOA community in low- and high-salinity samples, respectively. Nitrosomonas-AOB were detected in all samples while Nitrosospira-AOB were mainly found in relatively high-salinity samples. Regarding general Nitrospira, lineages II and IV were the major groups in most of the samples, while lineage I Nitrospira was only detected in low-salinity samples. Furthermore, the comammox pure culture of N. inopinata showed an optimal salinity at 0.5‰ and ceased to grow at 12.8‰ for ammonia oxidation, but remained active for nitrite oxidation. These results show new evidence regarding niche specificity of different nitrifying microorganisms modulated mainly by salinity, and also a clear response by comammox N. inopinata to a wide range of simulated salinity levels.


Asunto(s)
Ríos , Microbiología del Suelo , Amoníaco , Archaea , Bacterias/genética , Estuarios , Nitrificación , Oxidación-Reducción , Filogenia , Salinidad
15.
J Hazard Mater ; 416: 125834, 2021 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-33873034

RESUMEN

The increasing use of nanoparticles (NPs) has raised concerns about their potential environmental risks. Many researches on NPs focused on the toxicity mechanism to microorganisms, but neglect the toxicity effects in relation to nutritional conditions. Here, we evaluated the interactive effects of zinc oxide (ZnO) NPs and phosphorus (P) levels on the bacterial community and functioning of periphytic biofilms. Results showed that long-term exposure to ZnO NPs significantly reduced alkaline phosphatase activity (APA) of periphytic biofilms just in P-limited conditions. Co-occurrence network analysis indicated that ZnO NPs exposure reduced network complexity between bacterial taxa in P-limited conditions, while the opposite trend was observed in P-replete conditions. Correlation analysis and random forest modeling suggested that excessive Zn2+ released and high reactive oxygen species (ROS) production might be mainly responsible for the inhibition of APA induced by ZnO NPs under P-limited conditions, while adjustment of bacterial diversity and improvement of keystone taxa cooperation were the main mechanisms in maintaining APA when subjected to weak toxicity of ZnO NPs in P-replete conditions. Taken together, our results provide insights into the biological feedback mechanism involved in ZnO NPs exposure on the ecological function of periphytic biofilms in different P nutritional conditions.


Asunto(s)
Nanopartículas , Óxido de Zinc , Biopelículas , Retroalimentación , Nanopartículas/toxicidad , Fósforo , Óxido de Zinc/toxicidad
16.
Water Res ; 196: 117003, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33730544

RESUMEN

In this study, we evaluated the biotransformation mechanisms of lincomycin (LIN) and three fluoroquinolone antibiotics (FQs), ciprofloxacin (CFX), norfloxacin (NFX), and ofloxacin (OFX), which regularly enter aquatic environments through human activities, by different ammonia-oxidizing microorganisms (AOM). The organisms included a pure culture of the complete ammonia oxidizer (comammox) Nitrospira inopinata, an ammonia oxidizing archaeon (AOA) Nitrososphaera gargensis, and an ammonia-oxidizing bacterium (AOB) Nitrosomonas nitrosa Nm90. The removal of these antibiotics by the pure microbial cultures and the protein-normalized biotransformation rate constants indicated that LIN was significantly co-metabolically biotransformed by AOA and comammox, but not by AOB. CFX and NFX were significantly co-metabolized by AOA and AOB, but not by comammox. None of the tested cultures transformed OFX effectively. Generally, AOA showed the best biotransformation capability for LIN and FQs, followed by comammox and AOB. The transformation products and their related biotransformation mechanisms were also elucidated. i) The AOA performed hydroxylation, S-oxidation, and demethylation of LIN, as well as nitrosation and cleavage of the piperazine moiety of CFX and NFX; ii) the AOB utilized nitrosation to biotransform CFX and NFX; and iii) the comammox carried out hydroxylation, demethylation, and demethylthioation of LIN. Hydroxylamine, an intermediate of ammonia oxidation, chemically reacted with LIN and the selected FQs, with removals exceeding 90%. Collectively, these findings provide important fundamental insights into the roles of different ammonia oxidizers and their intermediates on LIN and FQ biotransformation in nitrifying environments including wastewater treatment systems.


Asunto(s)
Amoníaco , Nitrificación , Antibacterianos , Archaea , Biotransformación , Fluoroquinolonas , Humanos , Lincomicina , Nitrosomonas , Oxidación-Reducción , Filogenia , Microbiología del Suelo
17.
J Ethnopharmacol ; 268: 113563, 2021 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-33176184

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Kidney deficiency is the main pathogenesis of osteoporosis based on the theory of "kidney governing bones" in traditional Chinese medicine (TCM). Osteoporosis is a systemic disease; kidney deficiency influences the growth, aging and reproduction of human body, reflecting in endocrine, nerve, immunity, metabolism and other functions. Multi-target drugs composed of natural non-toxic products from kidney-reinforcing herbs, are being investigated for the treatment of osteoporosis. Therefore, it is necessary and imperative to develop an objective and comprehensive method to evaluate and compare the effects of herbs with listed drugs. AIM OF THE STUDY: This study was designed to evaluate and compare the therapeutic effects and the underlying molecular mechanism of the combined extracts of Epimedii Folium and Ligustri Lucidi Fructus (EL) with Raloxifene hydrochloride (RH) in ovariectomy (OVX)-induced postmenopausal osteoporosis (PMOP) rats based on the multi-layer perception (MLP)-artificial neural network (ANN) model. MATERIALS AND METHODS: Female SD rats were subjected to either sham surgery (n = 8) or bilateral OVX (n = 48). One week after recovering from surgery, the OVX-induced rats were randomly divided into three groups: OVX model group (n = 32, every 8 rats were killed at the end of the 5th, 9th, 11th or 13th week after OVX), EL group (treated with EL 0.35 g/kg, n = 8), and RH group (treated with RH 6.25 mg/kg, n = 8). The rats in the treatment groups were administrated once a day for 12 weeks, then sacrificed. We observed bone mass and quality, bone remodeling, the function of estrogen and TGF-ß1/Smads pathway in all rats. RESULTS: Both EL and RH could increase bone mineral density, enhance bone strength, relieve bone micro-structure degeneration, re-balance bone remodeling, regulate estrogen dysfunction, and up-regulate TGF-ß1 expression. The evaluation of the MLP-ANN model showed that EL and RH had markedly anti-PMOP effects, and there was no significant difference in the comprehensive evaluation of anti-osteoporosis between the two drugs. However, RH had better effects on bone mass and quality and TGF-ß1/Smads pathway than EL; EL had better effects on estrogen function than RH. CONCLUSION: Combined extracts of Epimedii Folium and Ligustri Lucidi Fructus (EL) exhibited bone-protective effects on PMOP. The MLP-ANN method evaluated the efficacy of drugs more comprehensively, which provided a new direction for the evaluation and comparison of drugs.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Medicamentos Herbarios Chinos/uso terapéutico , Ligustrum , Redes Neurales de la Computación , Osteoporosis Posmenopáusica/tratamiento farmacológico , Ovariectomía/efectos adversos , Animales , Densidad Ósea/fisiología , Evaluación Preclínica de Medicamentos/métodos , Medicamentos Herbarios Chinos/farmacología , Femenino , Frutas , Humanos , Osteoporosis Posmenopáusica/diagnóstico por imagen , Osteoporosis Posmenopáusica/metabolismo , Ratas , Ratas Sprague-Dawley , Microtomografía por Rayos X/métodos
18.
J Magn Reson Imaging ; 53(4): 1162-1174, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33098256

RESUMEN

BACKGROUND: Neurodegeneration is a complex cellular process linked to prompt changes in myelin integrity and gradual neuron loss. Current imaging techniques offer estimations of myelin volumes in lesions/remyelinated areas but are limited to detect subtle injury. PURPOSE: To investigate whether measurements detected by a signal hierarchically isolated as a function of time-to-echo (SHIFT) MRI technique can determine changes in myelin integrity and fiber axolemma. STUDY TYPE: Prospective animal model. ANIMAL MODEL: Surgically demyelinated spinal cord (SC) injury model in rodents (n = 6). FIELD STRENGTH/SEQUENCE: Gradient-echo spin-echo at 3T. ASSESSMENT: Multicompartment T2 relaxations were computed by SHIFT MRI in 75-microns-resolution images of the SC injury penumbra region 2 weeks post-trauma. G-ratio and axolemma delamination were assessed by transmission electron microscopy (TEM) in intact and injured samples. SC myelinated nerve fraction was computed by SHIFT MRI prospectively and assessed histologically. STATISTICAL TESTS: Relations between SHIFT-isolated T2 -components and TEM measurements were studied using linear regression and t-tests. Pearson's correlation and significance were computed to determine the SHIFT's sensitivity to detect myelinated fibers ratio in gray matter. Regularized least-squares-based ranking analysis was employed to determine SHIFT MRI's ability to discern intact and injured myelinated nerves. RESULTS: Biexponential signals isolated by SHIFT MRI for intact vs. lesion penumbra exhibited changes in T2 , shifting from intermediate components (25 ± 2 msec) to long (43 ± 11 msec) in white matter, and similarly in gray matter regions-of-interest (31 ± 2 to 46 ± 16 msec). These changes correlated highly with TEM g-ratio and axon delamination measurements (P < 0.05). Changes in short T2 components were observed but not statistically significant (8.5 ± 0.5 to 7 ± 3 msec, P = 0.445, and 4.0 ± 0.9 to 7 ± 3 msec, P = 0.075, respectively). SHIFT MRI's ability to detect myelinated fibers within gray matter was confirmed (P < 0.001). DATA CONCLUSION: Changes detected by SHIFT MRI are associated with abnormal intermembrane spaces formed upon mild injury, directly correlated with early neuro integrity loss. Level of Evidence 1 Technical Efficacy Stage 2.


Asunto(s)
Vaina de Mielina , Traumatismos de la Médula Espinal , Animales , Imagen por Resonancia Magnética , Neurópilo , Estudios Prospectivos , Médula Espinal/diagnóstico por imagen
19.
Front Microbiol ; 11: 589268, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33123118

RESUMEN

Complete ammonia oxidizers (comammox), able to individually oxidize ammonia to nitrate, are considered to play a Complete ammonia oxidizers (comammox), able to individually oxidize ammonia to nitrate, are considered to play a significant role in the global nitrogen cycle. However, the distribution of comammox Nitrospira in estuarine tidal flat wetland and the environmental drivers affecting their abundance and diversity remain unknown. Here, we present a large-scale investigation on the geographical distribution of comammox Nitrospira along the estuarine tidal flat wetlands of China, where comammox Nitrospira were successfully detected in 9 of the 16 sampling sites. The abundance of comammox Nitrospira ranged from 4.15 × 105 to 6.67 × 106 copies/g, 2.21- to 5.44-folds lower than canonical ammonia oxidizers: ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). Phylogenetic analysis based on the alpha subunit of the ammonia monooxygenase encoding gene (amoA) revealed that comammox Nitrospira Clade A, mainly originating from upstream river inputs, accounts for more than 80% of the detected comammox Nitrospira, whereas comammox Nitrospira clade B were rarely detected. Comammox Nitrospira abundance and dominant comammox Nitrospira OTUs varied within the estuarine samples, showing a geographical pattern. Salinity and pH were the most important environmental drivers affecting the distribution of comammox Nitrospira in estuarine tidal flat wetlands. The abundance of comammox Nitrospira was further negatively correlated with high ammonia and nitrite concentrations. Altogether, this study revealed the existence, abundance and distribution of comammox Nitrospira and the driving environmental factors in estuarine ecosystems, thus providing insights into the ecological niches of this recently discovered nitrifying consortium and their contributions to nitrification in global estuarine environments.

20.
Front Microbiol ; 11: 560942, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33101233

RESUMEN

After the discovery of complete ammonia-oxidizing (comammox) Nitrospira, detection and assessments of the contribution of comammox Nitrospira communities to nitrogen cycling are in great demand. PCR-based approach, a common method for the detection of comammox, depends strongly on accurate amplification of the amoA genes from the original DNA samples using appropriate primers. In this study, we reported an evaluation of the performance of two commonly used primer sets, Ntsp-amoA 162F/359R and comaA/B-244f/659r, for amplifying the comammox amoA genes from three representative wetland soils in China [Sangsang (SS), Sanjiang (SJ), and Xianghai (XH)]. Our results demonstrated the two primer sets could both successfully amplify the clades with high relative abundances (RA), and further revealed a broadly similar diversity and community composition of dominant comammox operational taxonomic units (OTUs) (RA ≥ 1%) in each of the three wetland soils. However, the clades with low RA, such as the clade A (1.26%) in SJ and the clade B (11.54%) in XH that were recovered by metagenomics analysis, failed to be amplified using comaA/B-244f/659r, but were successfully amplified and sequenced using Ntsp-amoA 162F/359R. It indicated that, compared to comaA/B-244f/659r, Ntsp-amoA 162F/359R was more sensitive to the clades with low RA. However, it is worth noting that Ntsp-amoA 162F/359R would overestimate the RA of some rare clades. For example, the RAs of clade B in XH were overestimated by 32-fold. Furthermore, high levels of non-target amplification were detected via gel electrophoresis using both primer sets, especially for comammox Clade B amoA genes, implying that we should treat qPCR results based on these primers with caution. Taken together, our study comprehensively compared the performance of the two primer sets on the sensitivity and specificity of amplifying comammox amoA genes in three wetland soils, pointing out the necessity of further development of new primers for the efficient and accurate detection of comammox in various environments.

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