Deciphering Multidrug-Resistant Plasmids in Disinfection Residual Bacteria from a Wastewater Treatment Plant.

Current disinfection processes pose an emerging environmental risk due to the ineffective removal of antibiotic-resistant bacteria, especially disinfection residual bacteria (DRB) carrying multidrug-resistant plasmids (MRPs). However, the characteristics of DRB-carried MRPs are poorly understood. In this study, qPCR analysis reveals that the total absolute abundance of four plasmids in postdisinfection effluent decreases by 1.15 log units, while their relative abundance increases by 0.11 copies/cell compared to investigated wastewater treatment plant (WWTP) influent. We obtain three distinctive DRB-carried MRPs (pWWTP-01-03) from postdisinfection effluent, each carrying 9-11 antibiotic-resistant genes (ARGs). pWWTP-01 contains all 11 ARGs within an ∼25 Kbp chimeric genomic island showing strong patterns of recombination with MRPs from foodborne outbreaks and hospitals. Antibiotic-, disinfectant-, and heavy-metal-resistant genes on the same plasmid underscore the potential roles of disinfectants and heavy metals in the coselection of ARGs. Additionally, pWWTP-02 harbors an adhesin-type virulence operon, implying risks of both antibiotic resistance and pathogenicity upon entering environments. Furthermore, some MRPs from DRB are capable of transferring and could confer selective advantages to recipients under environmentally relevant antibiotic pressure. Overall, this study advances our understanding of DRB-carried MRPs and highlights the imminent need to monitor and control wastewater MRPs for environmental security.

Microplastics exacerbate co-occurrence and horizontal transfer of antibiotic resistance genes.

Microplastic pollution is a rising environmental issue worldwide. Microplastics can provide a niche for the microbiome, especially for antibiotic-resistant bacteria, which could increase the transmission of antibiotic resistance genes (ARGs). However, the interactions between microplastics and ARGs are still indistinct in environmental settings. Microplastics were found to be significantly correlated with ARGs (p < 0.001), based on the analysis of samples taken from a chicken farm and its surrounding farmlands. Analysis of chicken feces revealed the highest abundance of microplastics (14.9 items/g) and ARGs (6.24 ×108 copies/g), suggesting that chicken farms could be the hotspot for the co-spread of microplastics and ARGs. Conjugative transfer experiments were performed to investigate the effects of microplastic exposure for different concentrations and sizes on the horizontal gene transfer (HGT) of ARGs between bacteria. Results showed that the microplastics significantly enhanced the bacterial conjugative transfer frequency by 1.4-1.7 folds indicating that microplastics could aggravate ARG dissemination in the environment. Potential mechanisms related to the up-regulation of rpoS, ompA, ompC, ompF, trbBp, traF, trfAp, traJ, and down-regulation of korA, korB, and trbA were induced by microplastics. These findings highlighted the co-occurrence of microplastics and ARGs in the agricultural environment and the exacerbation of ARGs' prevalence via rising the HGT derived from microplastics.

Clptm1, a new target in suppressing epileptic seizure by regulating GABAA R-mediated inhibitory synaptic transmission in a PTZ-induced epilepsy model.

Disruption of gamma-amino butyric acid type A receptors (GABAA Rs) synaptic clustering and a decrease in the number of GABAA Rs in the plasma membrane are thought to contribute to alteration of the balance between excitatory and inhibitory neurotransmission, which promotes seizure induction and propagation. The multipass transmembrane protein cleft lip and palate transmembrane protein 1 (Clptm1) controls the forward trafficking of GABAA R, thus decaying miniature inhibitory postsynaptic current (mIPSC) of inhibitory synapses. In this study, using a pentylenetetrazol (PTZ)-induced epilepsy rat model, we found that Clptm1 regulates epileptic seizures by modulating GABAA R-mediated inhibitory synaptic transmission. First, we showed that Clptm1 expression was elevated in the PTZ-induced epileptic rats. Subsequently, we found that downregulation of Clptm1 expression protected against PTZ-induced seizures, which was attributed to an increase in the number of GABAA Rγ2s in the plasma membrane and the amplitude of mIPSC. Taken together, our findings identify a new anti-seizure target that provides a theoretical basis for the development of novel strategies for the prevention and treatment of epilepsy.

[Evapotranspiration estimation using three-temperature model and influencing factors of Nanning City, China]. / åŸºäºŽä¸‰æ¸©æ¨¡åž‹çš„å—å®å¸‚è’¸æ•£é‡ä¼°ç®—åŠå ¶å½±å“å› ç´ .

Evapotranspiration is the key element of hydrological energy cycle and climate system. It is of great significance to estimate the spatiotemporal variation of evapotranspiration and its response to climate and land use changes for understanding the effects of water cycle and ecological processes in urban basins. Based on the three-temperature model and MODIS Image, we estimated and analyzed the spatiotemporal variation of evapotranspiration in Nanning City from 2001 to 2018, and examined the influence and driving mode of main climate factors and land use types on evapotranspiration. The results showed that the annual average evapotranspiration of Nanning City ranged from 495.7 to 781.1 mm during 2001-2018, with the inter annual relative variability ranging from -22.5% to 23.1%, showing an overall upward trend. The regional evapotranspiration showed a distribution pattern of high north-south and low middle, with the urban evapotranspiration being significantly lower than suburban area. The evapotranspiration had a significant multiple correlation with climate factors. The influence of temperature on the evapotranspiration was stronger than precipita-tion. Evapotranspiration was temperature driven in suburbs, but was driven by multiple factors in urban area. The average evapotranspiration of different land use types in Nanning was forests (823.4 mm) > grasslands (675.6 mm) > croplands (582.9 mm) > urban area (346.6 mm). The change of land use type was the main underlying surface factor leading to the significant change of regional evapotranspiration.

[Expression and Clinical Significance of LcnRNA XLOC_109948 in Patients with Acute Myeloid Leukemia].

OBJECTIVE: To detect the expression level of LncRNA XLOC_109948 in bone marrow and serum of patients with acute myeloid Leukemia (AML), to verify the consistency between the expression in bone marrow and serum and to explore the role of LncRNA XLOC_109948 expression in the occurrence a development of AML. METHODS: Bone marrow and peripheral blood samples were collected from 62 patients with AML, including 36 patients with AML (AML group), 26 AML patients with complete remission (AML-CR group), and peripheral blood from 20 healthy persons (control group) were also collected. The expression level of LncRNA XLOC_109948 was detected by real-time quantitative fluorescence PCR (qRT-PCR), and the relationship between its expression and clinical characteristics was analyzed. RESULTS: The expression of LncRNA XLOC_109948 in bone marrow and serum of AML patients was higher than that of AML patients with complete remission and healthy people (P<0.001). And there was no statistically significant difference between the AML-CR group and control group (P>0.05). The expression of LncRNA XLOC_109948 significantly decreased when AML patients reached to CR, and significantly increased when the disease relapsed (P<0.05). The expression of LncRNA XLOC_109948 significantly correlated with the clinicopathologic parameters of cytogenetics (P<0.05), but not significantly correlated with sex, age, WBC count, blast in bone marrow, FAB classification and other clinical characteristics (P>0.05). CONCLUSION: The expression of LncRNA XLOC_109948 in bone marrow and serum of AML patients is high, and its expression in time and sequence is consistent between bone marrow and serum, which can reflect the occurrence, development, chemotherapy efficacy and prognosis of AML patients.

[Evaluation of in vivo viability of human platelets cryopreserved at -80 degrees C by using SCID mouse model].

The purpose of this study was to evaluate the in vivo viability of human platelets cryopreserved at -80 degrees C by using SCID mouse model and flow cytometry. The fresh human platelets were frozen with 5% DMSO at -80 degrees C for 10 days, thawed, and centrifuged for concentration. A 100 ml aliquot of concentrated platelets was injected into the SCID mouse tail vein by using a 1 ml insulin-syringe fitted with a 29-gauge ultra-fine needle. The whole blood was collected into heparinized capillary tube at 0.5, 2, 4, 6, 12, and 24 hours after infusion via a tail vein and was labelled with CD61-PE. Then the human platelets in mouse whole blood were detected by flow cytometry. The 30 minute time point was used as 100% to calculate the survival time of human platelets. The results showed that the survival time of cryopreserved human platelets were more significantly decreased than that of fresh platelets in SCID mice. Survival rates at 4 hours after transfusion of fresh platelets and cryopreserved platelets in SCID mice were 79.5% +/- 9.1% (n = 8) and 40.6% +/- 6.6% (n = 8) respectively, and a T(1/2) estimated were 7 hours for fresh platelets, but 2.5 hours for the cryopreserved. In conclusion, platelets survival time in SCID mice was shortened after frozen with DMSO at -80 degrees C.