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1.
Sci Total Environ ; 788: 147798, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34034165

RESUMO

A link between microbial life history strategies and soil organic carbon storage in agroecosystems is presumed, but largely unexplored at the gene level. We aimed to elucidate whether and how differential organic material amendments (manure versus peat-vermiculite) affect, relative to sole chemical fertilizer application, the link between microbial life history strategies and soil organic carbon storage in a wheat-maize rotation field experiment. To achieve this goal, we combined bacterial 16S rRNA gene and fungal ITS amplicon sequencing, metagenomics and the assembly of genomes. Fertilizer treatments had a significantly greater effect on microbial community composition than aggregate size, with soil available phosphorus and potassium being the most important community-shaping factors. Limitation in labile carbon was linked to a K-selected oligotrophic life history strategy (Gemmatimonadetes, Acidobacteria) under sole chemical fertilizer application; defined by a significant enrichment of genes involved in resource acquisition, polymer hydrolysis, and competition. By contrast, excess of labile carbon promoted an r-selected copiotrophic life history strategy (Cytophagales, Bacillales, Mortierellomycota) under manure treatment; defined by a significant enrichment of genes involved in cellular growth. A distinct life history strategy was not observed under peat-vermiculite treatment, but rather a mix of both K-selected (Acidobacteria) and r-selected (Actinobacteria, Mortierellomycota) microorganisms. Compared to sole chemical fertilizer application, soil organic carbon storage efficiency was significantly increased by 26.5% and 50.0% under manure and peat-vermiculite treatments, respectively. Taken together, our results highlight the importance of organic material amendments, but in particular a one-time peat-vermiculite application, to promote soil organic carbon storage as a potential management strategy for sustainable agriculture.


Assuntos
Carbono , Solo , Agricultura , Fertilizantes/análise , Esterco , RNA Ribossômico 16S , Rotação , Microbiologia do Solo , Triticum , Zea mays
2.
Sci Total Environ ; 785: 147329, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33940418

RESUMO

The soil microbiome, existing as interconnected communities closely associated with soil aggregates, is the key driver in nutrient cycling. However, the underlying genomic information encoding the machinery of the soil microbiome involved in nutrient cycling at the soil aggregate scale is barely known. Here comparative metagenomics and genome binning were applied to investigate microbial functional profiles at the soil aggregate scale under different organic material amendments in a long-term field experiment. Soil samples were sieved into large macroaggregates (>2 mm), macroaggregates (0.25-2 mm) and microaggregates (<0.25 mm). Microbial taxonomic and functional alpha diversity were significantly correlated to soil NO3- and SOC. The highest abundance of nasB, nirK, and amoA genes, which are responsible for denitrification and ammonia oxidizers driving nitrification, was observed in microaggregates. Both manure and peat treatments significantly decreased the abundance of napA and nrfA that encode enzymes involved in dissimilatory nitrate reduction to ammonium (DNRA). As a biomarker for soil inorganic P solubilization, the relative abundance of gcd was significantly increased in macroaggregates and large macroaggregates. Three nearly complete genomes of Nitrososphaeraceae (AOA) and seven bacterial genomes were shown to harbor a series of genes involved in nitrification and P solubilization, respectively. Our study provides comprehensive insights into the microbial genetic potential for DNRA and P-solubilizing activity across different soil aggregate fractions and fertilization regimes.


Assuntos
Nitrogênio , Solo , Archaea , Metagenômica , Nitrificação , Fósforo , Microbiologia do Solo
3.
J Mater Chem B ; 9(6): 1478-1490, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33427844

RESUMO

Over the past decades, near infrared light (NIR)-sensitive photothermal agents (PTAs) that can efficiently absorb light and generate heat have been investigated worldwide for cancer photothermal therapy (PTT) and the combination treatments, which have some peculiar advantages including spatiotemporal targeting, the ability-to-reverse multidrug resistance, the immunity-stimulating function, and the synergistic effect in combination treatments. In this review, we first focus on emerging melanin-like polymers and coordination polyphenol polymer-based PTAs that hold transition potential because of their facile synthesis and good biocompatibility/biodegradability. We briefly introduce polymeric PTAs for emerging NIR-II (1000-1700 nm) PTT in deep tumors to overcome shallow penetration depth and threshold irradiation intensity of NIR-I (700-900 nm). Then we discuss polymeric PTAs for combination PTT treatments with photodynamic therapy (PDT), ferroptosis therapy (ferrotherapy), and immunotherapy, which are intensively studied for achieving anticancer synergistic effects. Finally, we discuss those polymeric PTAs for reversing cancer multidrug resistance and for mild/low-temperature PTT (43 °C ≤ T < 50 °C) in contrast to conventional high-temperature PTT (>50 °C). The polymeric PTA-based PTT and the combination treatments are still being developed in the early stage and need much more effort before potential clinical transitions and applications.


Assuntos
Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Polifenóis/farmacologia , Animais , Antineoplásicos/química , Sobrevivência Celular/efeitos dos fármacos , Humanos , Hipertermia Induzida , Neoplasias/patologia , Fármacos Fotossensibilizantes/química , Polifenóis/química
4.
Sci Adv ; 6(19): eaba2556, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32494726

RESUMO

Exosomes are nanoscale vesicles distinguished by characteristic biophysical and biomolecular features; current analytical approaches, however, remain univariate. Here, we develop a dedicated platform for multiparametric exosome analysis-through simultaneous biophysical and biomolecular evaluation of the same vesicles-directly in clinical biofluids. Termed templated plasmonics for exosomes, the technology leverages in situ growth of gold nanoshells on vesicles to achieve multiselectivity. For biophysical selectivity, the nanoshell formation is templated by and tuned to distinguish exosome dimensions. For biomolecular selectivity, the nanoshell plasmonics locally quenches fluorescent probes only if they are target-bound on the same vesicle. The technology thus achieves multiplexed analysis of diverse exosomal biomarkers (e.g., proteins and microRNAs) but remains unresponsive to nonvesicle biomarkers. When implemented on a microfluidic, smartphone-based sensor, the platform is rapid, sensitive, and wash-free. It not only distinguished biomarker organizational states in native clinical samples but also showed that the exosomal subpopulation could more accurately differentiate patient prognosis.

5.
J Int Med Res ; 47(6): 2702-2708, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31006299

RESUMO

Central vein perforation associated with a mediastinal lesion is a rare complication of catheterization. A 50-year-old woman was diagnosed with chronic kidney disease and required hemodialysis treatment. The patient developed central vein injury during attempted placement of a double-channel catheter. A computed tomographic scan and venography showed that the catheter had punctured the mediastinum from the central vein. After comprehensive assessment and multidisciplinary consultation, percutaneous catheter thrombin injection with follow-up balloon dilatation under fluoroscopy guidance successfully fixed the perforation. We summarize the therapeutic strategy of this complication and other treatment options, and discuss the related literature of central vein injury.


Assuntos
Cateterismo/efeitos adversos , Cateteres Venosos Centrais/efeitos adversos , Mediastino/patologia , Insuficiência Renal Crônica/terapia , Lesões do Sistema Vascular/terapia , Feminino , Humanos , Mediastino/irrigação sanguínea , Pessoa de Meia-Idade , Prognóstico , Diálise Renal , Lesões do Sistema Vascular/diagnóstico , Lesões do Sistema Vascular/etiologia
6.
IEEE Trans Neural Syst Rehabil Eng ; 25(12): 2516-2526, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29220327

RESUMO

This paper presents a hybrid brain-computer interface (BCI) that combines motor imagery (MI) and P300 potential for the asynchronous operation of a brain-controlled wheelchair whose design is based on a Mecanum wheel. This paradigm is completely user-centric. By sequentially performing MI tasks or paying attention to P300 flashing, the user can use eleven functions to control the wheelchair: move forward/backward, move left/right, move left45/right45, accelerate/decelerate, turn left/right, and stop. The practicality and effectiveness of the proposed approach were validated in eight subjects, all of whom achieved good performance. The preliminary results indicated that the proposed hybrid BCI system with different mental strategies operating sequentially is feasible and has potential applications for practical self-paced control.


Assuntos
Interfaces Cérebro-Computador , Potencial Evocado P300/fisiologia , Imaginação/fisiologia , Cadeiras de Rodas , Adulto , Algoritmos , Calibragem , Eletroencefalografia , Desenho de Equipamento , Feminino , Lateralidade Funcional , Voluntários Saudáveis , Humanos , Masculino , Adulto Jovem
7.
Psychiatry Res Neuroimaging ; 263: 113-120, 2017 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-28371656

RESUMO

There is a high degree of overlap between the symptoms of major depressive disorder (MDD) and schizophrenia, but it remains unclear whether the similar symptoms are derived from convergent alterations in functional network connectivity. In this study, we performed a group independent component analysis on resting-state functional MRI data from 20 MDD patients, 24 schizophrenia patients, and 43 matched healthy controls. The functional network connectivity analysis revealed that, compared to healthy controls, the MDD and schizophrenia patients exhibited convergent decreased positive connectivity between the left and right fronto-parietal control network and decreased negative connectivity between the left control and medial visual networks. Furthermore, the MDD patients showed decreased negative connectivity between the left control and auditory networks, and the schizophrenia patients showed decreased positive connectivity between the bilateral control and language networks and decreased negative connectivity between the right control and dorsal attention networks. The convergent network connectivity alterations may underlie the common primary control and regulation disorders, and the divergent connectivity alterations may enable the distinction between the two disorders. All of the convergent and divergent network connectivity alterations were relevant to the control network, suggesting an important role of the network in the pathophysiology of MDD and schizophrenia.


Assuntos
Transtorno Depressivo Maior/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem , Adulto , Transtorno Depressivo Maior/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/fisiopatologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Esquizofrenia/fisiopatologia
8.
Biomacromolecules ; 17(7): 2489-501, 2016 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-27310705

RESUMO

To integrate cocktail chemotherapy with photothermal therapy into one biocompatible and biodegradable nanocarrier, the plasmonic, lactose-targeted, and dual anticancer drugs-loaded polypeptide composite nanoparticles were for the first time fabricated under mild conditions. The glyco-PEGylated polypeptide micelles that self-assembled from the lactose (LAC) and PEG grafted polycysteine terpolymer were used as templates to generate the plasmonic composite nanoparticles, as mainly characterized by DLS, TEM, SEM, and XPS. These composite nanoparticles showed a broad and strong near-infrared (NIR) absorption at 650-1100 nm and increased the temperature of phosphate buffer solution by 30.1 °C upon a continuous-wave laser irradiation (808 nm, 5 min, 2 W·cm(-2)), while the same dose of NIR-mediated heating completely killed HepG2 cancer cells in vitro, presenting excellent photothermal properties. Two anticancer drugs, doxorubicin (DOX) and 6-mercaptopurine (6-MP), were loaded into the composite nanoparticles through physical interactions and Au-S bond, respectively. The dual drugs-loaded composite nanoparticles exhibited reduction-sensitive and NIR-triggered cocktail drugs release profiles and trigger-enhanced cytotoxicity. As evidenced by flow cytometry, fluorescence microscopy, and MTT assay, the LAC-coated composite nanoparticles were more internalized by the HepG2 than the HeLa cell line, demonstrating a LAC-targeting enhanced cytotoxicity toward HepG2. The combination cocktail chemo-photothermal therapy produced a lower half maximal inhibitory concentration than cocktail chemotherapy or photothermal therapy alone, displaying a good synergistic antitumor effect.


Assuntos
Doxorrubicina/farmacologia , Portadores de Fármacos/química , Mercaptopurina/farmacologia , Nanopartículas/química , Peptídeos/química , Fototerapia , Antibióticos Antineoplásicos/farmacologia , Antimetabólitos Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Terapia Combinada , Células HeLa , Células Hep G2 , Humanos , Nanopartículas/administração & dosagem , Peptídeos/administração & dosagem
9.
J Mater Chem B ; 4(12): 2142-2152, 2016 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-32263181

RESUMO

Biodegradable, biocompatible polypeptide micelles were used as a reducing agent and template in an autoreduction method for preparing plasmonic gold-embedded polypeptide micelles under mild conditions. The micelles were fully characterized by DLS, TEM, SEM, and AFM. The in situ reduced gold was embedded in the interior core of the disulfide bond-cross-linked polypeptide micelles by forming multivalent Au-S bonds. The plasmonic gold-embedded micelles showed strong near-infrared (NIR) light absorption and NIR-mediated photothermal properties including high photothermal conversion efficiency and good photostability. After continuous-wave diode laser irradiation for 5 min (808 nm, 2 W cm-2), the NIR light-induced heating of the gold-embedded micelles efficiently killed cancer cells in vitro, as observed by a double fluorescent staining technique. A standard MTT assay, flow cytometry, and fluorescence microscopy showed that the anticancer drug doxorubicin (DOX)-loaded and gold-embedded micelles quickly entered HeLa cells and gave a lower half-maximal inhibitory concentration (IC50) than for chemotherapy or photothermal therapy alone, demonstrating a good synergistic effect for the combination chemo-photothermal therapy. Consequently, this work provides a versatile strategy for fabricating plasmonic polypeptide composite nanoparticles, which are promising for synergistic chemo-photothermal cancer therapy.

10.
Macromol Rapid Commun ; 36(10): 916-22, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25833346

RESUMO

Inspired by sweet or sugar-coated bullets that are used for medications in clinics and the structure and function of biological melanin, a novel kind of sweet polydopamine nanoparticles and their anticancer drug doxorubicin loaded counterparts are prepared, which integrate an active targeting function, photothermal therapy, and chemotherapy into one polymeric nanocarrier. The oxidative polymerization of lactosylated dopamine and/or with dopamine are performed under mild conditions and the resulting sweet nanoparticles are thoroughly characterized. When exposed to an 808 nm continuous-wave diode laser, the magnitude of temperature elevation not only increases with the concentration of nanoparticles, but can also be tuned by the laser power density. The nanoparticles possess strong near infrared light absorption, high photothermal conversion efficiency, and good photostability. The nanoparticles present tunable binding with RCA120 lectin and a targeting effect to HepG2 cells, confirmed by dynamic light scattering, turbidity analysis, MTT assay, and flow cytometry. Importantly, the sweet nanoparticles give the lowest IC50 value of 11.67 µg mL(-1) for chemo-photothermal therapy compared with 43.19 µg mL(-1) for single chemotherapy and 67.38 µg mL(-1) for photothermal therapy alone, demonstrating a good synergistic effect for the combination therapy.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Portadores de Fármacos , Indóis/síntese química , Polímeros/síntese química , Antibióticos Antineoplásicos/química , Sobrevivência Celular/efeitos dos fármacos , Terapia Combinada , Doxorrubicina/química , Composição de Medicamentos , Células HeLa , Células Hep G2 , Humanos , Lactose/química , Luz , Terapia com Luz de Baixa Intensidade , Melaninas/química
12.
Zhonghua Fu Chan Ke Za Zhi ; 44(11): 821-4, 2009 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-20079032

RESUMO

OBJECTIVE: To study the efficacy of different anti-adhesion agents used in preventing tubal obstruction after recanalization. METHODS: Five hundred and eight patients with tubal obstruction were divided into 245 cases in control group, 108 cases in chitosan group; 113 cases in sodium hyaluronate group and 42 cases in lipiodol group. The patients in control group were injected with anti-inflammation agents after recanalization, while other groups were injected with chitosan, sodium hyaluronate or lipiodol at dose of 2 - 3 ml in every therapeutic group. The rate of location of tubal obstruction and tubal recanalization were recorded during operation. Then patients in every group were followed up on tubal patency after 3 months, and pregnancy rate after 12 months. RESULTS: Among 1016 fallopian tubes in 508 patients, there were 330 tubes occlusion at isthmus portion and 563 tubes occlusion at interstitial portion of fallopian tube. Thirty-seven fallopian tubes were ablated because of ectopic pregnancy, 86 fallopian tubes were unobstructed. (1) The recanalization rate were 95.7% (179/187) in chitosan group, 97.9% (191/195) in sodium hyaluronate group, 98.7% (75/76) in lipiodol group and 97.7% (425/435) in control group, which did not show statistical difference (P > 0.05). (2) The rates of tubal patency after 3 months of 91.7% (99/108) in chitosan group and 88.5% (100/113) in sodium hyaluronate group were significantly higher than 71.4% (30/42) in lipiodol group and 74.3% (182/245) in control group (P < 0.05). (3) The rates of intrauterine pregnancy after 12 months were 48.1% (52/108) in chitosan group and 41.6% (47/113) in sodium hyaluronate group, which were significantly higher than 23.8% (10/42) in lipiodol group and 24.1% (59/245) in control group (P < 0.05). CONCLUSION: Chitosan and sodium hyaluronate could be effective to prevent tubal obstruction after interventional recanalization and increase pregnancy rate.


Assuntos
Doenças das Tubas Uterinas , Histerossalpingografia , Animais , Doenças das Tubas Uterinas/cirurgia , Tubas Uterinas/cirurgia , Humanos , Taxa de Gravidez , Esterilização Tubária
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