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1.
Microb Ecol ; 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36372840

RESUMO

Fungal communities are essential to the maintenance of soil multifunctionality. Plant invasion represents a growing challenge for the conservation of soil biodiversity across the globe, but the impact of non-native species invasion on fungal diversity, community structure, and assembly processes remains largely unknown. Here, we examined the diversity, community composition, functional guilds, and assembly process of fungi at three soil depths underneath a native species, three non-native species, and a bare tidal flat from a coastal wetland. Plant species was more important than soil depth in regulating the diversity, community structure, and functional groups of fungi. Non-native species, especially Spartina alterniflora, increased fungal diversity, altered fungal community structure, and increased the relative abundance of saprotrophic and pathogenic fungi in coastal wetland soils. Stochastic processes played a predominant role in driving fungal community assembly, explaining more than 70% of the relative contributions. However, compared to a native species, non-native species, especially S. alterniflora, reduced the relative influence of stochastic processes in fungal community assembly. Collectively, our results provide novel evidence that non-native species can increase fungal diversity, the relative abundance of saprotrophic and pathogenic fungi, and deterministic processes in the assembly of fungi in coastal wetlands, which can expand our knowledge of the dynamics of fungal communities in subtropical coastal wetlands.

2.
Ying Yong Sheng Tai Xue Bao ; 33(6): 1622-1628, 2022 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-35729141

RESUMO

Subtropical region of China is one of the global hotspots receiving nitrogen deposition. Nitrogen deposition could affect the abundance and community structure of ammonia oxidizers including ammonia-oxidizing bacteria (AOB), ammonia-oxidizing archaea (AOA) and complete ammonia oxidizer (comammox Nitrospira), with consequences on soil nutrient cycling that are driven by microorganisms. There is limited understanding for the newly discovered comammox Nitrospira in the subtropical forest soils. Here, we investigated the effect of simulated N deposition on abundances of soil ammonia oxidizers in the Castanopsis fargesii Nature Reserve in Xinkou Town, Sanming City, Fujian Province, China. Soil samples were collected from the field plots which received long-term nitrogen deposition with different dosages, including: CK, no additional treatment; LN, low nitrogen deposition treatment, dosage of 40 kg N·hm-2·a-1; and HN, high nitrogen deposition treatment, dosage of 80 kg N·hm-2·a-1. After 8-year treatment, simulated N deposition decreased soil pH and organic matter content, and increased nitrate content. We failed to amplify the amoA gene of AOB in the tested soils. High nitrogen deposition increased the abundance of AOA, but did not affect the abundance of comammox Nitrospira clade A and clade B. The ratio of comammox Nitrospira to AOA decreased with N addition, indicating that N addition weakened the role of comammox Nitrospira in nitrification in the subtropical forest soils. However, there were strong non-specific amplifications for both comammox Nitrospira clades A and B, highlighting the demand for the development of high coverage and specificity primers for comammox Nitrospira investigations in the future. The abundance of comammox Nitrospira clade A was positively correlated with total nitrogen (TN) and NH4+ concentration, while that of clade B was positively associated with soil organic carbon (SOC), TN and NH4+ Concentration. Overall, our findings demonstrated that simulated N deposition increased the relative importance of AOA in nitrification in the natural Castanopsis carlesii forest soil. These findings could provide theoretical support in coping with global change and N deposition in these regions.


Assuntos
Amônia , Solo , Archaea/genética , Bactérias/genética , Carbono , Florestas , Nitrificação , Nitrogênio , Oxirredução , Filogenia , Solo/química , Microbiologia do Solo
3.
Microb Ecol ; 2022 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-35034141

RESUMO

Plant species play a crucial role in mediating the activity and community structure of soil microbiomes through differential inputs of litter and rhizosphere exudates, but we have a poor understanding of how plant species influence comammox Nitrospira, a newly discovered ammonia oxidizer with pivotal functionality. Here, we investigate the abundance, diversity, and community structure of comammox Nitrospira underneath five plant species and a bare tidal flat at three soil depths in a subtropical estuarine wetland. Plant species played a critical role in driving the distribution of individual clades of comammox Nitrospira, explaining 59.3% of the variation of community structure. Clade A.1 was widely detected in all samples, while clades A.2.1, A.2.2, A.3 and B showed plant species-dependent distribution patterns. Compared with the native species Cyperus malaccensis, the invasion of Spartina alterniflora increased the network complexity and changed the community structure of comammox Nitrospira, while the invasive effects from Kandelia obovata and Phragmites australis were relatively weak. Soil depths significantly influenced the community structure of comammox Nitrospira, but the effect was much weaker than that from plant species. Altogether, our results highlight the previously unrecognized critical role of plant species in driving the distribution of comammox Nitrospira in a subtropical estuarine wetland.

4.
Org Biomol Chem ; 19(30): 6588-6592, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34023869

RESUMO

Using visible light as a driving force and molecular oxygen as a green oxidant, we developed bis(oxazoline)-Ni(acac)2 catalyzed asymmetric α-hydroxylation of ß-keto esters under low photosensitizer loading, and the protocol enabled an efficient transformation to provide the desired chiral α-hydroxy-ß-keto esters in high yields (up to 99%) and enantioselectivities (up to 99% ee) at room temperature.

5.
Ann Palliat Med ; 10(2): 2036-2047, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33549019

RESUMO

BACKGROUND: To compare the efficacy and safety of PSORI-CM01 granules with Yinxieling tablets in patients with chronic plaque psoriasis (CPP), we plan to conduct a multicentre, randomized, double-blinded, double-dummy, controlled trial. This pilot study was conducted to determine the feasibility and the potential of the protocol for the full-scale randomized controlled trial (RCT). METHODS: This pilot study was conducted in three centers, and compared PSORI-CM01 granules with Yinxieling tablets in patients with CPP during a 12-week treatment and 3-month follow-up period. The primary efficacy endpoint was the decrease of the psoriasis area severity index (PASI) at week 12. The secondary outcome measures included reduction rates of PASI, pruritus scores on the Visual Analogue Scale (VAS), body surface area (BSA), and the Dermatology Life Quality Index (DLQI). Safety was assessed via the incidence of adverse events (AEs) in each treatment group. RESULTS: A total of 211 patients were screened, and 63 subjects who met the inclusion criteria were randomised to PSORI-CM01 granule group (N=31) or Yinxieling tablets group (N=32) while 39 subjects finished the study. The primary outcome measure showed a mean decrease of PASI of 2.03 in the PSORICM01 group compared to 0.89 in the Yinxieling group at week 12. Except for the VAS score (t=-2.261, P=0.027), the secondary outcomes showed no significant improvement from baseline in both groups at week 12. No safety or tolerability concerns related to the drugs were observed in either group. CONCLUSIONS: This pilot study showed that the RCT is feasible for randomization, patient recruitment, and assessment. Major strategies are necessary to reduce the patient dropout rate before conducting the full RCT. In this pilot study, the PSORI-CM01 granule exhibited greater potential for development compared to its original formula (Yinxieling tablets) for the treatment of CPP.


Assuntos
Medicamentos de Ervas Chinesas , Psoríase , Método Duplo-Cego , Humanos , Projetos Piloto , Psoríase/tratamento farmacológico , Índice de Gravidade de Doença , Comprimidos , Resultado do Tratamento
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