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BackgroundThe incidence of nosocomial candidemia has increased in recently years, however, the epidemiological data remain insufficient in China.MethodsA total of 234 candidemia patients were included from Xiamen University Zhong Shan hospital between January 2006 and October 2024. Incidence, species proportion, distribution, antifungal drug resistance of candidemia was analyzed. A nomogram model for 30-day morbidity of candidemia was determined using the least absolute shrinkage and logistic regression analysis.ResultsThe incidence of candidemia increased in recent years (2020: 0.025%, 2021: 0.029%, 2023:0.022%). The dominant species of candidemia were Candida albicans (n=99,42.31%), Candida parapsilosis (n=47,20.09%), Candida tropicalis (n=43,18.38%), Candida glabrata (n=31,13.25%). Departments with a higher detection of candidemia included intensive care unit (n=55), emergency department (n=24) and hepatobiliary surgery (n=22). Candida tropicalis performed the highest resistance to azole (fluconazole: 55.81%, voriconazole:55.00% and itraconazole:58.14%). The resistance of Candida albicans to fluconazole, voriconazole and itraconazole were 32.32%, 23.53% and 31.31%. The mortality rate of 30-day discharge for candidemia reached 52.99%. 205 cases of candidemia patients from January 2006 to December 2023 were included as the training set, while 29 cases of candidiasis patients from January to October 2004 were included as the validation set. Five independent factors included Candida albicans, decreased albumin, multiple organ dysfunction syndrome, solid tumor and septic shock were adopted in a nomogram for 30-days mortality of candidemia. In the training set, the area under curve was 0.866 (95%CI: 0.817-0.916), the optimal cutoff value was 0.617, the sensitivity was 80% and the specificity was 80.4%. In the validation set, the area under curve was 0.808 (95%CI:0.737-0.970), the optimal cutoff value was 0.543. The sensitivity was 72.7% and the specificity was 83.3%.ConclusionThe incidence of nosocomial candidemia has risen in recent years. Candida albicans remains the primary species, with the highest incidence is intensive care unit. Candida tropicalis exhibits the highest resistance rate to azole drugs. A nomogram predicting 30-day mortality discharge for candidemia patients has been constructed, and the independent risk factors including Candida albicans, multiple organ dysfunction syndrome, septic shock, solid tumors, and decreased albumin.

Clinically used inhibitors of mammalian target of rapamycin (mTOR) negatively impacts endothelial-dependent vasodilatation (EDD) through unidentified mechanisms. Here we show that either the endothelium-specific deletion of Mtor to inhibit both mTOR complexes, or depletion of Raptor or Rictor to disrupt mTORC1 or mTORC2, causes impaired EDD, accompanied by reduced NO in the serum of mice. Consistently, inhibition of mTOR decreases NO production by human and mouse EC. Specifically, inhibition of mTORC1 suppresses eNOS gene expression, due to impairment in p70S6K-mediated posttranscriptional regulation of the transcription factor KLF2 expression. In contrast to mTORC1 inhibition, a positive-feedback between MAPK (p38 and JNK) activation and Nox2 upregulation contributes to the excessive generation of reactive oxygen species (ROS), which causes eNOS uncoupling and decreased NO bioavailability in mTORC2-inhibited EC. Adeno-associated virus-mediated EC-specific overexpression of KLF2 or suppression of Nox2 restores EDD function in endothelial mTORC1- or mTORC2-inhibited mice.

[Objective] This study is aimed at comprehensively evaluating the soil quality of different vegetation restoration types in the mountainous areas of Beijing, and further identifying the key factors affecting soil quality, so as to provide data support for vegetation restoration and reconstruction in the region. [Methods] The study utilized various vegetation types, including Platycladus orientalis pure forest, Pinus tabulaeformis pure forest, P. orientalis-P. tabulaeformis mixed forest, P. orientalis coniferous and broadleaved mixed forest, P. tabulaeformis coniferous and broadleaved mixed forest, deciduous broad-leaved mixed forest, and non-forest land (CK), with similar stand conditions, as research objects. Fourteen soil physical and chemical indicators were measured to establish the total data set (TDS) for evaluating soil quality. Principal component analysis (PCA) and Pearson correlation analysis were employed to determine the minimum data set (MDS) for soil quality evaluation. Two scoring methods, linear (L) and non-linear (NL), were used to calculate the soil quality index (SQI) and a general linear model (GLM) was employed to identify key factors influencing soil quality. [Results] The bulk density and sand content decreased, while the content of soil nutrients such as organic matter, total nitrogen, total potassium, available nitrogen, and available potassium increased after the vegetation restoration compared with the non-forest land. The screened MDS indicators for soil quality evaluation in the study area were total nitrogen (TN), sand content, total potassium (TK), pH, and available water capacity (AWC). Under the four methods (SQI-LT, SQI-NLT, SQI-LM, and SQI-NLM), the SQI values of different vegetation restoration types were ranked as deciduous broadleaf mixed forest > P. orientalis coniferous and broadleaved mixed forest > P. tabulaeformis pure forest > P. tabulaeformis coniferous and broadleaved mixed forest > P. orientalis-P. tabulaeformis mixed forest > P. orientalis pure forest > non-forest land, and the soil quality significantly improved after vegetation restoration. The soil quality evaluation method of SQI-NLM exhibited better applicability in the mountainous areas of Beijing. Compared with non-forested land, the SQI-NLM of other vegetation restoration types improved by 64%, 48%, 45%, 36%, 33% and 27%, respectively. The GLM model accounted for 85.24% of the total variation in the soil quality index, with vegetation type explaining the largest proportion of the soil quality index (45.09%). [Conclusion] The selection of suitable vegetation restoration types is crucial for improving regional soil quality. In future vegetation restoration efforts, priority should be given to broad-leaved species in tree species selection. Additionally, the choice of silvicultural configuration should depend on the tree species, such as introducing native broad-leaved species into Platycladus orientalis pure forest to form a Platycladus orientalis coniferous and broadleaved mixed forest, or selecting Pinus tabulaeformis pure forest as the optimal silvicultural model.

An analytic model is used to calculate the Raman and fluorescence enhancement of a molecule in between two closely spaced gold nanospheres. Instead of using the conventional approach that only the dipolar plasmonic mode is considered, we calculate the electric field enhancement in the nanometre sized gap, by taking account of the higher order modes in one gold sphere, which couples to the dipolar mode of the other sphere. The experimental confirmation is performed by gap-dependent tip-enhanced Raman spectroscopy (TERS) measurements. The photoluminescence and Raman enhancement are both observed with different growing trends as the gap width decreases. Red-shift of the background spectra is observed and implies the increasing coupling between the nanospheres. This analytic model is shown to be able to interpret the enhancement mechanisms underlying gap-dependent TERS experimental results.