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Liao, Q.

Publications and source records attributed to Liao, Q..

4 recordsLinked to original sources

Population based hospitalization burden of laboratory-confirmed hand, foot and mouth disease caused by multiple enterovirus serotypes in southern China

BackgroundHand, foot and mouth disease (HFMD) is spread widely across Asia, and the hospitalization burden is as yet not well understood. Here, we estimated serotype-specific and age-specific hospitalization rates of HFMD in Southern China.\n\nMethodsWe enrolled pediatric patients admitted to 3/3 county-level hospitals and 3/23 township level hospitals in Anhua county, Hunan (CN) with HFMD, and collected samples to identify enterovirus serotypes by RT-PCRs between October 2013 and September 2016. The information of other eligible but un-enrolled patients were retrospectively collected from the same six hospitals. Monthly number of hospitalizations for all causes was collected from each of 23 township level hospitals to extrapolate hospitalizations associated with HFMD among these.\n\nResultsDuring the three years, an estimated 3,236 pediatric patients were hospitalized with lab-confirmed HFMD, and among these only one patient was severe. The mean hospitalization rates were 660 (95% CI: 638-684) per 100,000 person-years for lab-confirmed HFMD, with higher rates among CV-A16 and CV-A6 associated HFMD (213 vs 209 per 100,000 person-years), and lower among EV-A71, CV-A10 and other enteroviruses associated HFMD (134, 39 and 66 per 100,000 person-years, p<0.001). Children aged 12-23 months had the highest hospitalization rates (3,594/100,000 person-years), followed by those aged 24-35 months (1,828/100,000 person-years) and 6-11 months (1,572/100,000 person-years). Compared with other serotypes, CV-A6-associated hospitalizations were evident at younger ages.\n\nConclusionsOur study indicates a substantial hospitalization burden associated with non-severe HFMD in a rural county in southern China. Future mitigation policies should take into account the disease burden identified, and optimize interventions for HFMD.

epidemiology

NRT1.1-dependent NH4+ toxicity in Arabidopsis is associated with disturbed balance between NH4+ uptake and assimilation

A high concentration of a sole ammonium (NH4+) source in growth media is often toxic to plants. The nitrate transporter NRT1.1 is involved in plant NH4+ toxicity; however, its mechanism remains undefined. In this study, wild-type Arabidopsis (Col-0) and NRT1.1 mutants (chl1-1 and chl1-5) were grown hydroponically in NH4NO3 and (NH4)2SO4 media to evaluate NRT1.1 function in NH4+ stress responses. All plants grew normally in mixed N sources, but Col-0 displayed more chlorosis, and lower biomass and photosynthesis than the NRT1.1 mutants in the (NH4)2SO4 condition. Grafting experiments between Col-0 and chl1-5 further confirmed that NH4+ toxicity is NRT1.1-dependent. In (NH4)2SO4 medium, NRT1.1 facilitated the higher expression of NH4+ transporters, increasing NH4+ uptake. Additionally, glutamine synthetase (GS) and glutamate synthetase (GOGAT) in roots of Col-0 plants decreased and soluble sugar accumulated significantly, whereas pyruvate kinase (PK)-mediated glycolysis was not affected, all of which contributed to NH4+ accumulation. In contrast, the NRT1.1 mutants reduced NH4+ accumulation and enhanced NH4+ assimilation through glutamate dehydrogenase (GDH) and glutamate-oxaloacetate transamination (GOT) activity. In addition, the upregulation of genes involved in senescence in Col-0 plants treated with (NH4)2SO4 suggests that ethylene could be involved in NH4+ toxicity responses. Our results indicate that NH4+ toxicity is dependent on NRT1.1 in Arabidopsis, characterized by enhanced NH4+ accumulation and by perturbed NH4+ metabolism, which stimulated ethylene-induced plant senescence.\n\nHighlight: Nitrate transporter NRT1.1 enhances NH4+ accumulation, disturbs the NH4+ metabolism, and aggravates NH4+ toxicity in Arabidopsis when grown under sole NH4+ condition.

plant biology

Mitochondrial Methylation Two-Peak Profile Absent in Parkinson's Disease Patient

Whole-mitochondrial genome methylation profiles were obtained for mitochondrial DNA (mtDNA) from blood samples of one sporadic Parkinsons Disease (PD) patient and one healthy control donor, via Whole-Genome Next-Generation Bisulfite Sequencing. Methylation frequency was determined at 836 CpG sites out of the 1146 CpG sites in mtDNA (73% of the total). The control mtDNA methylation profile exhibited a two-peak frequency distribution, with most CpG sites showing either no methylation, or a methylation above 7%. Instead, the sporadic PD mtDNA methylation profile exhibited a generic bell-shaped frequency distribution. The data is suggestive of the bell-shaped methylation profile arising via a degradation towards randomness of the healthy sample two-peak methylation pattern. Overall, this finding provides a possible explanation for the repeated observation of PD-phenotypic characteristics in cybrid cell lines where solely the mtDNA originates from a PD patient. We discuss the finding in terms of the sporadic PD Hematopoietic Origin Theory (HOT).

cell biology

DNA 5-Hydroxymethylcytosines from Cell-free Circulating DNA as Diagnostic Biomarkers for Human Cancers

DNA modifications such as 5-methylcytosines (5mC) and 5-hydroxymethylcytosines (5hmC) are epigenetic marks known to affect global gene expression in mammals(1, 2). Given their prevalence in the human genome, close correlation with gene expression, and high chemical stability, these DNA epigenetic marks could serve as ideal biomarkers for cancer diagnosis. Taking advantage of a highly sensitive and selective chemical labeling technology(3), we report here genome-wide 5hmC profiling in circulating cell-free DNA (cfDNA) and in genomic DNA of paired tumor/adjacent tissues collected from a cohort of 90 healthy individuals and 260 patients recently diagnosed with colorectal, gastric, pancreatic, liver, or thyroid cancer. 5hmC was mainly distributed in transcriptionally active regions coincident with open chromatin and permissive histone modifications. Robust cancer-associated 5hmC signatures in cfDNA were identified with specificity for different cancers. 5hmC-based biomarkers of circulating cfDNA demonstrated highly accurate predictive value for patients with colorectal and gastric cancers versus healthy controls, superior to conventional biomarkers, and comparable to 5hmC biomarkers from tissue biopsies. This new strategy could lead to the development of effective blood-based, minimally-invasive cancer diagnosis and prognosis approaches.

cancer biology