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Objectives: Citrobacter spp. especially Citrobacter freundii, is frequently causing nosocomial infections, and increasingly becoming multi-drug resistant (MDR). In this study, we aimed to determine the genetic diversity and relationships of Citrobacter spp. from diarrheal patients and food sources, their antimicrobial resistance profiles and in vitro virulence properties.Methods: Sixty two Citrobacter isolates, including 13 C. freundii, 41 C. youngae and eight C. braakii isolates, were obtained from human diarrheal patients and food sources. Multilocus Sequence Typing (MLST) of seven housekeeping genes and antimicrobial susceptibility testing using the broth microdilution method according to CLSI recommendations were carried out. Adhesion and cytotoxicity to HEp-2 cells were performed. PCR and sequencing were used to identify blaCTX−M, blaSHV, blaTEM and qnr genes.Results: The 62 isolates were divided into 53 sequence types (STs) with all STs being novel, displaying high genetic diversity. ST39 was a predominant ST shared by 5 C. youngae strains isolated from four foods and a diarrheal patient. All isolates were resistant to cefoxitin, and sensitive to imipenem, meropenem and amikacin. The majority of Citrobacter isolates (61.3%) were MDR of three or more antibiotics out of the 22 antibiotics tested. Two C. freundii isolates each carried the blaTEM−1 gene and a variant of qnrB77. Three Citrobacter isolates each carried qnrS1 and aac(6')-Ib-cr genes. Seven isolates that showed strong cytotoxicity to HEp-2 cells were MDR.Conclusions: Citrobacter spp. from human and food sources are diverse with variation in virulence properties and antibiotic resistance profiles. Food may be an important source of Citrobacter species in transmission to humans. C. freundii and C. youngae are potential foodborne pathogens.

1. Characterizing patterns of variation in plant traits across species and environmental gradients is critical for understanding performance of species in ecosystems.One-dimensional pattern of variation has been demonstrated in leaf traits, which is known as the leaf economic spectrum. However, it is unclear whether such a spectrum exists for root traits.2. For roots of 15 species from temperate grasslands, we determined respiration rate, relative growth rate, life span and 10 morphological, chemical and anatomical root traits. We further evaluated pairwise and multiple-trait relationships by Pearson's correlation and principle component analysis including phylogenetic contrasts.3. We found that root functions were related to three clusters of variation. Root respiration rate and relative growth rate were positively correlated with average root diameter (AD), but they were negatively correlated with specific root length (SRL). In contrast, root life span was not correlated with AD, but it was positively correlated with SRL. These results are inconsistent with the presumption of the root economic spectrum. 4. The principle components analysis revealed a multi-dimensional pattern of variation in root traits among the 15 coexisting herbaceous species. Moreover, species within the same phylogenetic clades tended to have similar root trait syndromes.Most of the root traits exhibited a significant phylogenetic signal. Synthesis.Our results do not support a one-dimensional root economic spectrum in the coexisting herbaceous species of temperate grasslands. In contrast, the pattern of variation in root traits was multi-dimensional. We further demonstrated that species in different phylogenetic clades possess diverse root trait syndromes for efficient resource acquisition. Our findings provide a next step in understanding root functions and plant strategies in temperate grasslands. K E Y W O R D Scoexisting species, phylogenetic clades, phylogeny, resource acquisition, root economic spectrum, root traits, temperate grasslands | 2321Journal of Ecology ZHOU et al.

Aristolochic acids (AAs) are a group of toxins commonly present in the plants of genus Aristolochia and Asarum , which are spread all over the world. Since the 1990s, AA-induced nephropathy (AAN) and upper tract urothelial carcinoma (UTUC) have been reported in many countries. The underlying mechanisms of AAN and AA-induced UTUC have been extensively investigated. AA-derived DNA adducts are recognized as specific biomarkers of AA exposure, and a mutational signature predominantly characterized by A→T transversions has been detected in AA-induced UTUC tumor tissues. In addition, various enzymes and organic anion transporters are involved in AA-induced adverse reactions. The progressive lesions and mutational events initiated by AAs are irreversible, and no effective therapeutic regimen for AAN and AA-induced UTUC has been established until now. Because of several warnings on the toxic effects of AAs by the US Food and Drug Administration and the regulatory authorities of some other countries, the sale and use of AA-containing products have been banned or restricted in most countries. However, AA-related adverse events still occur, especially in the Asian and Balkan regions. Therefore, the use of AA-containing herbal remedies and the consumption of food contaminated by AAs still carry high risk. More strict precautions should be taken to protect the public from AA exposure.

Monitoring intracorporal pressures are important for health care and diagnosis. In this work, a contact lens tonometer employing graphene woven fabrics (GWFs), which indicate great sensibility of resistance to strain, flexibility, stretchability, transparency, and biocompatibility, is proposed for real-time monitoring intraocular pressure (IOP) with high resolution. The mechanical properties of the device during the deformation were analyzed, and the sensitivity of the fabricated device was tested on a mimic human eyeball. In vitro experiments on porcine eyes were executed to test the effectiveness of the device. The change rate of resistance under different IOP was tested. Also, the relationship between the current changes and IOP variation when keeping the voltage constant for different devices was obtained. The contact lens tonometers with GWFs as high-resolution sensing element have shown a promising prospective to realize the low-cost disposable sensing contact lens with lower power.

Adrenal primitive neuroectodermal tumor is a very rare tumor. It originates in primitive neuroectoderma and is found mainly in 20-30-year-old young populations. It has non-specific clinical or imaging manifestation and its diagnosis is mostly based on pathological examinations. The tumor is fast-developing, highly malignant with poor prognosis.

Renal cell carcinoma (RCC) is the second most lethal urinary cancer. RCC is frequently asymptomatic and it is already metastatic at diagnosis. There is an urgent necessity for RCC specific biomarkers selection for diagnostic and prognostic purposes. In present study, we applied liquid chromatography—mass spectrometry (LC-MS) based metabolomics to analyze urine samples of 100 RCC, 34 benign kidney tumors and 129 healthy controls. Differential metabolites were analyzed to investigate if urine metabolites could differentiate RCC from non-RCC. A panel consisting of 9 metabolites showed the best predictive ability for RCC from the health controls with an area under the curve (AUC) values of 0.905 for the training dataset and 0.885 for the validation dataset. Separation was observed between the RCC and benign samples with an AUC of 0.816. RCC clinical stages (T1 and T2 vs. T3 and T4) could be separated using a panel of urine metabolites with an AUC of 0.813. One metabolite, N-formylkynurenine, was discovered to have potential value for RCC diagnosis from non-RCC subjects with an AUC of 0.808. Pathway enrichment analysis indicated that tryptophan metabolism was an important pathway in RCC. Our data concluded that urine metabolomics could be used for RCC diagnosis and would provide candidates for further targeted metabolomics analysis of RCC.