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1.
Microorganisms ; 12(6)2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38930499

RESUMEN

Soil desertification is an important challenge in global soil management, and effectively and stably restoring soil function is an urgent problem. Using synthetic microbial communities (SynComs) is a burgeoning microbial strategy aimed at enhancing soil nutrients through functional synergies among diverse microorganisms; nevertheless, their effectiveness in restoring desertified soils remains unknown. In this study, we conducted a two-year field experiment using a SynCom constructed by in situ probiotic bacteria and set up control, chemical fertilizer, and combined SynCom-chemical fertilizer (combined fertilizer) treatments to investigate the linkage between microbial communities and soil multifunctionality in the soil surface layer (0-10 cm). Both the bacterial and fungal communities differed the most under the combined fertilizer treatment compared to the control. The bacterial communities differed more under treatments of the SynCom than the chemical fertilizer, while the fungal communities differed more under the chemical fertilizer treatment than the SynCom treatment. Regarding soil function, the SynCom strengthened the correlation between enzyme activities and both bacterial communities and functional properties. pH and available potassium were the main influencing factors under the chemical fertilizer and combined fertilizer treatments. The beta-diversity of the bacterial communities was significantly correlated with soil multifunctionality. Random forest analyses showed that the SynCom significantly enhanced the bacterial communities, driving soil multifunctionality, and that some potential microbial taxa drove multiple nutrient cycles simultaneously. In summary, the SynCom effectively increased the abundance of most carbon, nitrogen, and phosphorus functional genes as well as soil enzyme activities. The bacterial community composition contributed significantly to soil multifunctionality. Hence, the development of novel microbial agents holds significant potential for improving soil functionality and managing desertification.

2.
Heliyon ; 10(7): e28958, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38601655

RESUMEN

Purpose: The occurrence of hyponatremia is a prevalent complication following transnasal transsphenoidal surgery for pituitary adenoma surgery, which adversely affects patient prognosis, hospitalization duration, and rehospitalization risk. The primary objective of this study is to strengthen the correlation between clinical factors associated with pituitary adenoma and postoperative hyponatremia. Additionally, the study aims to develop a predictive model for postoperative hyponatremia in patients with pituitary adenoma, with the ultimate goal of establishing a basis for reducing the occurrence of postoperative hyponatremia following surgical interventions. Methods: The chi-square test or Fisher test was employed for nominal data, while the t-test or Mann-Whitney test was utilized for continuous data analysis. In cases where the data exhibited statistical differences, binary logistic analysis was conducted to examine the risk and protective factors associated with postoperative hyponatremia. XGBoost was employed to construct predictive models for hyponatremia in this study. The patients were partitioned into training and test sets, and the most suitable parameters were determined through five-fold cross-validation and subsequently utilized for training on the training set. The discriminatory capability was assessed on the internal validation set. Results and conclusions: Out of the total 280 patients included in this investigation, 82 patients experienced early postoperative hyponatremia. Among these individuals, male gender (P = 0.02, odds ratio = 1.98) was identified as a risk factor for early postoperative hyponatremia, while preoperative chloride levels (P = 0.021, odds ratio = 0.866) and surgery time (P = 0.039, odds ratio = 0.990) were identified as protective factors against postoperative hyponatremia. The XGBoost model exhibited a sensitivity of 94.2%, a specificity of 61.5%, a positive predictive value of 51.6%, a negative predictive value of 96%, and identified male gender, preoperative sodium, and preoperative cortisol as the most significant predictors. Our findings indicate that gender may have influence in the development of early postoperative hyponatremia in patients with pituitary adenomas.

3.
J Hazard Mater ; 469: 133956, 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38460258

RESUMEN

Polyhalogenated carbazoles (PHCZs), an emerging persistent halogenated organic pollutant, have been detected in the environment. However, our understanding of PHCZs in the ocean remains limited. In this study, 47 seawater samples (covering 50 - 4000 m) and sediment samples (49 surface and 3 cores) were collected to investigate the occurrence and spatial distribution patterns of carbazole and its halogenated derivants (CZDs) in the Western Pacific Ocean. In seawater, the detection frequencies of CZ (97.87%) and 3-CCZ (57.45%) were relatively high. In addition, the average concentration of ΣPHCZs in the upper water (< 150 m, 0.23 ± 0.21 ng/L) was significantly lower than that in the deep ocean (1000 - 4000 m, 0.65 ± 0.56 ng/L, P < 0.05), which may indicate the vertical transport of PHCZs in the marine environment. The concentration of ΣCZDs in surface sediment ranges from 0.46 to 6.48 ng/g (mean 1.54 ng/g), among which CZ and 36-CCZ were the predominant components. Results from sediment cores demonstrate a noteworthy negative correlation between the concentration of CZDs and depth, indicating the ongoing natural degradation process occurring in sediment cores over a long period. This study offers distinctive insights into the occurrence, composition, and vertical features of CZDs in oceanic environments.

4.
Mar Pollut Bull ; 198: 115915, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38091632

RESUMEN

A total of 13 surface sediments were collected from Hangzhou Bay (HZB) for an investigation into the distribution and influencing factors of anammox bacterial community. The anammox bacterial 16S rRNA and hzo genes ranged between 2.34 × 105 to 9.22 × 105 copies/g and 3.68 × 105 to 1.70 × 106 copies/g, respectively. The results of high throughput sequencing (HTS) revealed that the obtained OTUs were affiliated with five known genera, named Ca. Scalindua, Ca. Jettenia, Ca. Brocadia, Ca. Kuenenia and Ca. Anammoxoglobus. RDA analysis indicated that salinity, pH, and water depth influenced the anammox bacterial community. Furthermore, network analysis identified Ca. Scalindua as a key genus. Neutral community model (NCM) and modified stochasticity ratio (MST) indicated that the deterministic process dominated the anammox bacterial community assembly. Overall, this study offers a more comprehensive understanding of the abundance and community of anammox bacteria in the sediments of HZB.


Asunto(s)
Compuestos de Amonio , Oxidación Anaeróbica del Amoníaco , ARN Ribosómico 16S/genética , Bahías , Sedimentos Geológicos/microbiología , Oxidación-Reducción , Bacterias/genética , China , Filogenia
5.
Environ Pollut ; 341: 123008, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38006990

RESUMEN

Cold seep sediments are an important reservoir of microplastics (MPs) whose impact on the structure and function of prokaryotic community is not well understood. In this study, the impact of 0.2% and 1% (w/w) polyethylene (PE), polystyrene (PS), and polypropylene (PP) MPs on the cold seep sediment prokaryotic community was investigated in a 120-day laboratory incubation experiment. The results revealed that exposure to MPs altered sedimentary chemical properties in a type- and concentration-dependent manner. Furthermore, MPs significantly altered the structure of bacterial community, with some MPs degradation-associated bacterial phyla significantly increasing (p < 0.05). However, in the case of archaea, the changes in the structure of microbial community were less pronounced (p > 0.05). Co-occurrence network analysis revealed that the addition of MPs reduced the network complexity, while PICRUSt2 and FAPROTAX analyses suggested that 0.2% PP and 1% PS MPs had the most significant effects on the nitrogen and carbon cycles (p < 0.05). Overall, this study provides new insights into the effects of MPs on the structure and function of microbial communities in cold seep sediments.


Asunto(s)
Microplásticos , Plásticos , Bacterias , Archaea , Polipropilenos , Poliestirenos
6.
Elife ; 122023 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-37728319

RESUMEN

Sirtuins (SIRT) exhibit deacetylation or ADP-ribosyltransferase activity and regulate a wide range of cellular processes in the nucleus, mitochondria, and cytoplasm. The role of the only sirtuin that resides in the cytoplasm, SIRT2, in the development of ischemic injury and cardiac hypertrophy is not known. In this paper, we show that the hearts of mice with deletion of Sirt2 (Sirt2-/-) display improved cardiac function after ischemia-reperfusion (I/R) and pressure overload (PO), suggesting that SIRT2 exerts maladaptive effects in the heart in response to stress. Similar results were obtained in mice with cardiomyocyte-specific Sirt2 deletion. Mechanistic studies suggest that SIRT2 modulates cellular levels and activity of nuclear factor (erythroid-derived 2)-like 2 (NRF2), which results in reduced expression of antioxidant proteins. Deletion of Nrf2 in the hearts of Sirt2-/- mice reversed protection after PO. Finally, treatment of mouse hearts with a specific SIRT2 inhibitor reduced cardiac size and attenuates cardiac hypertrophy in response to PO. These data indicate that SIRT2 has detrimental effects in the heart and plays a role in cardiac response to injury and the progression of cardiac hypertrophy, which makes this protein a unique member of the SIRT family. Additionally, our studies provide a novel approach for treatment of cardiac hypertrophy and injury by targeting SIRT2 pharmacologically, providing a novel avenue for the treatment of these disorders.


Asunto(s)
Factor 2 Relacionado con NF-E2 , Sirtuina 2 , Animales , Ratones , Cardiomegalia/prevención & control , Isquemia/metabolismo , Miocitos Cardíacos/metabolismo , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Sirtuina 2/metabolismo
7.
Biomimetics (Basel) ; 8(4)2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37622948

RESUMEN

With the rapid development of enabling technologies like VR and AR, we human beings are on the threshold of the ubiquitous human-centric intelligence era. 6G is believed to be an indispensable cornerstone for efficient interaction between humans and computers in this promising vision. 6G is supposed to boost many human-centric applications due to its unprecedented performance improvements compared to 5G and before. However, challenges are still to be addressed, including but not limited to the following six aspects: Terahertz and millimeter-wave communication, low latency and high reliability, energy efficiency, security, efficient edge computing and heterogeneity of services. It is a daunting job to fit traditional analytical methods into these problems due to the complex architecture and highly dynamic features of ubiquitous interactive 6G systems. Fortunately, deep learning can circumvent the interpretability issue and train tremendous neural network parameters, which build mapping relationships from neural network input (status and specific requirements of a 6G application) to neural network output (settings to satisfy the requirements). Deep learning methods can be an efficient alternative to traditional analytical methods or even conquer unresolvable predicaments of analytical methods. We review representative deep learning solutions to the aforementioned six aspects separately and focus on the principles of fitting a deep learning method into specific 6G issues. Based on this review, our main contributions are highlighted as follows. (i) We investigate the representative works in a systematic view and find out some important issues like the vital role of deep reinforcement learning in the 6G context. (ii) We point out solutions to the lack of training data in 6G communication context. (iii) We reveal the relationship between traditional analytical methods and deep learning, in terms of 6G applications. (iv) We identify some frequently used efficient techniques in deep-learning-based 6G solutions. Finally, we point out open problems and future directions.

8.
Int J Neurosci ; : 1-10, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37646218

RESUMEN

BACKGROUND: Ischemic stroke (IS) is a highly prevalent type of stroke with very high rates of disability and death. As the regulatory role of circular RNAs (circRNAs) in various diseases has been revealed, we constructed a stroke cell model to analyze the action mechanism of hsa_circ_0005548 in IS. METHODS: The abundance of hsa_circ_0005548, microRNA-362-3p (miR-362-3p) and E26 transformation specific-1 (ETS-1) were measured by real-time quantitative polymerase chain reaction (RT-qPCR) or western blot. We constructed an IS cell model in vitro by oxygen-glucose deprivation/reperfusion (OGD/R) treatment and analyzed cell proliferation, apoptosis and inflammatory response through the use of Cell Counting Kit-8 (CCK8), 5-ethynyl-2'-deoxyuridine (EdU), flow cytometry and Enzyme-linked immunosorbent assay (ELISA), respectively. Dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were employed for the analysis of the relationship between miR-362-3p and hsa_circ_0005548 or ETS1. RESULTS: The higher abundance of hsa_circ_0005548 and ETS-1 and lower level of miR-362-3p were observed in human brain microvascular endothelial immortalized (HBMEC-IM) cells under OGD/R. Hsa_circ_0005548 downregulation mitigated OGD/R-induced HBMEC-IM cell injury. Mechanistically, hsa_circ_0005548 targeted miR-362-3p. MiR-362-3p knockdown reversed the effect of hsa_circ_0005548 silencing on OGD/R-induced HBMEC-IM cell injury. ETS1 was validated as a direct target of miR-362-3p, and miR-362-3p attenuated OGD/R-induced HBMEC-IM cell injury by ETS1. Moreover, hsa_circ_0005548 modulated ETS1 via miR-362-3p. CONCLUSION: Hsa_circ_0005548 knockdown repairs OGD/R-induced HBMEC-IM cell damage via miR-362-3p/ETS1 axis.

9.
J Colloid Interface Sci ; 649: 528-534, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37356154

RESUMEN

The grain boundary defects of polycrystalline perovskite could induce severe carrier recombination loss to restrict the photovoltaic and stability advancement of perovskite-based solar cells (PSCs). Inserting fixed molar ratio organic cations spacers into halide perovskite slabs to reduce the dimension of the crystal structure is still limited in finding a compromise of efficiency and stability for the widened bandgap and increasing barriers for carrier transport. Here, we select a direct additive bridging engineering to introduce a rationally designed organic amine salt 1,4-Benzene diammonium iodide (BDAI2) with ammonium group on both terminals of the benzene ring to passivate the grain boundary and interface defects of perovskite. Bridging diammonium could ameliorate the interface contact and achieve electrostatic interactions with negatively charged traps (such as uncoordinated I-, PbI3-, and methylammonium vacancies) to inhibit cation migration, reduce halogen ion vacancy, and then suppress trap-induced recombination in perovskite. As a result, the bridging diammonium could improve the power conversion efficiency (PCE) from 19.86% to 21.91%. This study highlights the importance of rational bridging diammonium for perovskite surface modification and passivation to boost photovoltaic performance and stability.

10.
Small ; 19(32): e2303200, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37178255

RESUMEN

The interface between the perovskite and electron-transporting material is often treated for defect passivation to improve the photovoltaic performance of devices. A facile 4-Acetamidobenzoic acid (containing an acetamido, a carboxyl, and a benzene ring)-based molecular synergistic passivation (MSP) strategy is developed here to engineer the SnOx /perovskite interface, in which dense SnOx are prepared using an E-beam evaporation technology while the perovskite is deposited with vacuum flash evaporation deposition method. MSP engineering can synergistically passivate defects at the SnOx /perovskite interface by coordinating with Sn4+ and Pb2+ with functional group CO in the acetamido and carboxyl. The optimized solar cell devices can achieve the highest efficiency of 22.51% based on E-Beam deposited SnOx and 23.29% based on solution-processed SnO2 , respectively, accompanied by excellent stability exceeding 3000 h. Further, the self-powered photodetectors exhibit a remarkably low dark current of 5.22 × 10-9  A cm-2 , a response of 0.53 A W-1 at zero bias, a detection limit of 1.3 × 1013  Jones, and a linear dynamic range up to 80.4 dB. This work proposes a molecular synergistic passivation strategy to enhance the efficiency and responsivity of solar cells and self-powered photodetectors.

11.
Front Neurol ; 14: 1045929, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37188306

RESUMEN

Background and objective: Post-operative pneumonia (POP), a common complication, may be associated with prolonged hospitalization and long-term mortality in aneurysmal subarachnoid hemorrhage (aSAH) patients. This study aimed to explore the association between pre-operative prognostic nutrition index (PNI) and POP in aSAH patients. Methods: A total of 280 aSAH patients were enrolled from Nanjing Drum Tower Hospital. PNI was calculated as follows: [10 × albumin(gr/dl)] + [0.005 × absolute pre-operative lymphocyte count (per mm3)]. We utilized multivariate analyses, restricted cubic spline, net reclassification improvement (NRI), and integrated discrimination improvement (IDI) to elucidate the role of PNI in POP. Results: Pre-operative PNI levels in the POP group were higher, compared with the non-POP group (41.0 [39.0, 45.4] vs. 44.4 [40.5, 47.3], P = 0.001). When we included PNI as a categorical variable in the multivariate analysis, the levels of PNI were associated with POP (odds ratio, 0.433; 95% confidence interval, 0.253-0.743; P=0.002). In addition, when we included PNI as a continuous variable in the multivariate analysis, the PNI levels were also associated with POP (odds ratio, 0.942; 95% confidence interval, 0.892-0.994; P = 0.028). The level of albumin was also a predictor of the occurrence of POP, with a lower diagnostic power than PNI [AUC: 0.611 (95% confidence interval, 0.549-0.682; P = 0.001) for PNI vs. 0.584 (95% confidence interval, 0.517-0.650; P = 0.017) for albumin]. Multivariable-adjusted spline regression indicated a linear dose-response association between PNI and POP in aSAH participants (P for linearity = 0.027; P for non-linearity = 0.130). Reclassification assessed by IDI and NRI was significantly improved with the addition of PNI to the conventional model of POP in aSAH patients (NRI: 0.322 [0.089-0.555], P = 0.007; IDI: 0.016 [0.001-0.031], P = 0.040). Conclusion: The lower levels of pre-operative PNI may be associated with the higher incidence of POP in aSAH patients. Neurosurgeons are supposed to pay more attention to pre-operative nutrition status in aSAH patients.

12.
Sci Total Environ ; 881: 163366, 2023 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37044349

RESUMEN

To date, multiple studies have shown that the accumulation of microplastics (MPs)/nanoplastics (NPs) in the environment may lead to various problems. However, the effects of MPs/NPs on microbial communities and biogeochemical processes, particularly methane metabolism in cold seep sediments, have not been well elucidated. In this study, an indoor microcosm experiment for a period of 120 days exposure of MPs/NPs was conducted. The results showed that MPs/NPs addition did not significantly influence bacterial and archaeal richness in comparison with the control (p > 0.05), whereas higher levels of NPs (1 %, w/w) had a significant adverse effect on bacterial diversity (p < 0.05). Moreover, the bacterial community was more sensitive to the addition of MPs/NPs than the archaea, and Epsilonbacteraeota replaced Proteobacteria as the dominant phylum in the MPs/NPs treatments (except 0.2 % NPs). With respect to the co-occurrence relationships, network analysis showed that the presence of NPs, in comparison with MPs, reduced microbial network complexity. Finally, the presence of MPs/NPs decreased the abundance of mcrA, while promoting the abundance of pmoA. This study will help elucidate the responses of microbial communities to MPs/NPs and evaluate their effects on methane metabolism in cold seep ecosystems.


Asunto(s)
Microbiota , Plásticos , Plásticos/metabolismo , Polietileno/metabolismo , Bacterias/metabolismo , Archaea/metabolismo , Microplásticos/metabolismo , Metano/metabolismo
13.
Chemosphere ; 330: 138763, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37094722

RESUMEN

Oil pollution in intertidal zones is an important environmental issue that has serious adverse effects on coastal ecosystems. This study investigated the efficacy of a bacterial consortium constructed from petroleum degraders and biosurfactant producers in the bioremediation of oil-polluted sediment. Inoculation of the constructed consortium significantly enhanced the removal of C8-C40n-alkanes (80.2 ± 2.8% removal efficiency) and aromatic compounds (34.4 ± 10.8% removal efficiency) within 10 weeks. The consortium played dual functions of petroleum degradation and biosurfactant production, greatly improving microbial growth and metabolic activities. Real-time quantitative polymerase chain reaction (PCR) showed that the consortium markedly increased the proportions of indigenous alkane-degrading populations (up to 3.88-times higher than that of the control treatment). Microbial community analysis demonstrated that the exogenous consortium activated the degradation functions of indigenous microflora and promoted synergistic cooperation among microorganisms. Our findings indicated that supplementation of a bacterial consortium of petroleum degraders and biosurfactant producers is a promising bioremediation strategy for oil-polluted sediments.


Asunto(s)
Microbiota , Contaminación por Petróleo , Petróleo , Petróleo/análisis , Bacterias/genética , Bacterias/metabolismo , Biodegradación Ambiental , Alcanos/metabolismo , Contaminación por Petróleo/análisis , Hidrocarburos/metabolismo
14.
bioRxiv ; 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36747794

RESUMEN

Sirtuins (SIRT) exhibit deacetylation or ADP-ribosyltransferase activity and regulate a wide range of cellular processes in the nucleus, mitochondria and cytoplasm. The role of the only sirtuin that resides in the cytoplasm, SIRT2, in the development of heart failure (HF) and cardiac hypertrophy is not known. In this paper, we show that the hearts of mice with deletion of Sirt2 ( Sirt2 -/- ) display improved cardiac function after ischemia-reperfusion (I/R) and pressure overload (PO), suggesting that SIRT2 exerts maladaptive effects in the heart in response to stress. Similar results were obtained in mice with cardiomyocyte-specific Sirt2 deletion. Mechanistic studies suggest that SIRT2 modulates cellular levels and activity of nuclear factor (erythroid-derived 2)-like 2 (NRF2), which results in reduced expression of antioxidant proteins. Deletion of Nrf2 in the hearts of Sirt2 -/- mice reversed protection after PO. Finally, treatment of mouse hearts with a specific SIRT2 inhibitors reduces cardiac size and attenuates cardiac hypertrophy in response to PO. These data indicate that SIRT2 has detrimental effects in the heart and plays a role in the progression of HF and cardiac hypertrophy, which makes this protein a unique member of the SIRT family. Additionally, our studies provide a novel approach for treatment of cardiac hypertrophy by targeting SIRT2 pharmacologically, providing a novel avenue for the treatment of this disorder.

15.
Stem Cell Res Ther ; 14(1): 17, 2023 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-36737797

RESUMEN

BACKGROUND: Many laboratories have described the in vitro isolation of multipotent cells with stem cell properties from the skin of various species termed skin-derived stem cells (SDSCs). However, the cellular origin of these cells and their capability to give rise, among various cell types, to male germ cells, remain largely unexplored. METHODS: SDSCs were isolated from newborn mice skin, and then differentiated into primordial germ cell-like cells (PGCLCs) in vitro. Single-cell RNA sequencing (scRNA-seq) was then applied to dissect the cellular origin of SDSCs using cells isolated from newborn mouse skin and SDSC colonies. Based on an optimized culture strategy, we successfully generated spermatogonial stem cell-like cells (SSCLCs) in vitro. RESULTS: Here, using scRNA-seq and analyzing the profile of 7543 single-cell transcriptomes from newborn mouse skin and SDSCs, we discovered that they mainly consist of multipotent papillary dermal fibroblast progenitors (pDFPs) residing in the dermal layer. Moreover, we found that epidermal growth factor (EGF) signaling is pivotal for the capability of these progenitors to proliferate and form large colonies in vitro. Finally, we optimized the protocol to efficiently generate PGCLCs from SDSCs. Furthermore, PGCLCs were induced into SSCLCs and these SSCLCs showed meiotic potential when cultured with testicular organoids. CONCLUSIONS: Our findings here identify pDFPs as SDSCs derived from newborn skin and show for the first time that such precursors can be induced to generate cells of the male germline.


Asunto(s)
Células Germinativas , Células Madre Hematopoyéticas , Animales , Ratones , Células Germinativas/metabolismo , Diferenciación Celular , Células Madre Multipotentes , Células Cultivadas , Fibroblastos
16.
J Hazard Mater ; 442: 129999, 2023 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-36152549

RESUMEN

The distribution characteristics and drivers of carbazole (CZ) and polyhalogenated carbazoles are still poorly understood. In this study, 96 samples were collected around the Zhoushan Archipelago, and their distribution characteristics were assessed. The results showed that CZ, 36-CCZ, and 36-BCZ were the top three abundant congeners in most collected samples. The bioaccumulation analysis revealed that marine plants prefer to accumulate CZ and bromocarbazoles rather than chlorocarbazoles. Both the mean concentrations of total carbazole and its derivants (ΣCZDs), as well as individual congeners, are the highest in sediments around the berthing areas of cargo ships and oil tankers. Meanwhile, ΣCZDs of these sediments are significantly influenced by the geo-weighted displacement of ships (r = 0.61; p < 0.05), indicating the ballast water from these ships as potential contributor for marine CZDs. Moreover, the accumulation of CZ in plankton, planktonic origin of sedimentary organic matter, and relationship between CZ and C/N ratio (p < 0.05) in sediments support the scenario that plankton absorbs and takes CZ into the sediments. These findings will promote the understanding of the sources, environmental behaviors, and fates of marine CZDs.


Asunto(s)
Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Carbazoles , Navíos , Agua/análisis , Sedimentos Geológicos/análisis , Monitoreo del Ambiente/métodos
17.
Infect Drug Resist ; 15: 6731-6737, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36444214

RESUMEN

Purpose: Beta-lactamase-producing Klebsiella pneumoniae is common in the clinic, but research associated with the co-existence of KPC-2, LAP-2, and CTX-M-65 in K. pneumoniae is still rare. In this study, the phenotypic and genetic characteristics of a multidrug-resistant K. pneumoniae strain SJ25 co-harboring bla KPC-2, bla LAP-2, and bla CTX-M-65 with rare ST1469 were investigated. Methods and Results: Antimicrobial susceptibility testing revealed that strain SJ25 was resistant to various common antibiotics, except ciprofloxacin, fosfomycin, colistin, and tigecycline. Whole-genome analysis revealed that strain SJ25 carries a variety of antimicrobial resistance genes and virulence determinants. Plasmid analysis confirmed that the bla KPC-2 and bla CTX-M-65 genes were located on an ~136 kb transferrable IncFII/IncR plasmid and that bla LAP-2 was located on an untypeable plasmid. Conclusion: Our findings emphasized the need for continuous surveillance of ß-lactamase-bearing K. pneumoniae in the clinic to control potential dissemination and outbreak.

18.
J Clin Med ; 11(12)2022 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-35743480

RESUMEN

Early brain injury is considered to be a primary reason for the poor prognosis of patients suffering from subarachnoid hemorrhage (SAH). Due to its pro-inflammatory activity, cold-inducible RNA-binding protein (CIRP) has been implicated in the ischemic brain insult, but its possible interplay with hypothermia in SAH treatment remains to be evaluated. One-hundred and thirty-eight Sprague-Dawley rats (300-350 g males) were randomly allocated into the following groups: sham-operated (Sham); SAH; and SAH + hypothermia (SAH + H), each comprised of 46 animals. After treatments, the brain tissues of the three groups were randomly collected after 12 h, 1 d, 3 d, and 7 d, and the expression levels of the CIRP and mitochondrial apoptosis pathway-related proteins Bax, Bcl-2, caspase-9, caspase-3, and cytochrome c measured using Western blotting and real-time PCR. Brain damage was assessed by TUNEL and Nissl staining, the electron microscopy of brain tissue slices as well as functional rotarod tests. Expression of CIRP, Bax, caspase-9, caspase-3, and cytochrome c as well as reduced motor function incidence were higher in the SAH group, particularly during the first 3 d after SAH induction. Hypothermia blunted these SAH responses and apoptosis, thereby indicating reduced inflammatory signaling and less brain cell injury in the early period after SAH. Hypothermia treatment was found to effectively protect the brain tissue from early SAH injury in a rat model and its further evaluation as a therapeutic modality in SAH patients requires further study.

19.
Front Cell Infect Microbiol ; 12: 879409, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35601097

RESUMEN

Mobile colistin resistance (mcr) genes represent an emerging threat to public health. Reports on the prevalence, antimicrobial profiles, and clonality of MCR-9-producing Enterobacter cloacae complex (ECC) isolates on a national scale in China are limited. We screened 3,373 samples from humans, animals, and the environment and identified eleven MCR-9-positive ECC isolates. We further investigated their susceptibility, epidemiology, plasmid profiles, genetic features, and virulence potential. Ten strains were isolated from severe bloodstream infection cases, especially three of them were recovered from neonatal sepsis. Enterobacter hormaechei was the most predominant species among the MCR-9-producing ECC population. Moreover, the co-existence of MCR-9, CTX-M, and SHV-12 encoding genes in MCR-9-positive isolates was globally observed. Notably, mcr-9 was mainly carried by IncHI2 plasmids, and we found a novel ~187 kb IncFII plasmid harboring mcr-9, with low similarity with known plasmids. In summary, our study presented genomic insights into genetic characteristics of MCR-9-producing ECC isolates retrieved from human, animal, and environment samples with one health perspective. This study is the first to reveal NDM-1- and MCR-9-co-producing ECC from neonatal sepsis in China. Our data highlights the risk for the hidden spread of the mcr-9 colistin resistance gene.


Asunto(s)
Colistina , Sepsis Neonatal , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , China/epidemiología , Colistina/farmacología , Enterobacter , Pruebas de Sensibilidad Microbiana , Sepsis Neonatal/epidemiología , Plásmidos/genética , beta-Lactamasas
20.
Sci Total Environ ; 831: 154904, 2022 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-35364163

RESUMEN

Microplastics (MPs) and polychlorinated biphenyls (PCBs) generally coexist in the environment, posing risks to public health and the environment. This study investigated the effect of different MPs on the microbial anaerobic reductive dechlorination of Aroclor 1260, a commercial PCB mixture. MP exposure inhibited microbial reductive dechlorination of PCBs, with inhibition rates of 39.43%, 23.97%, and 17.53% by polyethylene (PE), polypropylene (PP), and polystyrene (PS), respectively. The dechlorination rate decreased from 1.63 µM Cl- d-1 to 0.99-1.34 µM Cl- d-1 after MP amendment. Chlorine removal in the meta-position of PCBs was primarily inhibited by MPs, with no changes in the final PCB dechlorination metabolites. The microbial community compositions in MP biofilms were not significantly different (P > 0.05) from those in suspension culture, although possessing greater Dehalococcoides abundance (0.52-0.81% in MP biofilms; 0.03-0.12% in suspension culture). The co-occurrence network analysis revealed that the presence of MPs attenuated microbial synergistic interactions in the dechlorinating culture systems, which may contribute to the inhibitory effect on microbial PCB dechlorination. These findings are important for comprehensively understanding microbial dechlorination behavior and the environmental fate of PCBs in environments with co-existing PCBs and MPs and for guiding the application of in situ PCB bioremediation.


Asunto(s)
Chloroflexi , Bifenilos Policlorados , Arocloros , Biodegradación Ambiental , Cloro/metabolismo , Chloroflexi/metabolismo , Sedimentos Geológicos , Microplásticos , Plásticos/metabolismo , Bifenilos Policlorados/metabolismo
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