Dysfunction of Emotion Regulation in Mild Cognitive Impairment Individuals Combined With Depressive Disorder: A Neural Mechanism Study.

Depression increases the risk of progression from mild cognitive impairment (MCI) to dementia, where impaired emotion regulation is a core symptom of depression. However, the neural mechanisms underlying the decreased emotion regulation in individuals with MCI combined with depressive symptoms are not precise. We assessed the behavioral performance by emotion regulation tasks and recorded event-related electroencephalography (EEG) signals related to emotion regulation tasks simultaneously. EEG analysis, including event-related potential (ERP), event-related spectral perturbation (ERSP), functional connectivity and graph theory, was used to compare the difference between MCI individuals and MCI depressed individuals in behavioral performance, the late positive potential (LPP) amplitudes, neural oscillations and brain networks during the processing of emotional stimuli. We found that MCI depressed individuals have negative preferences and are prone to allocate more attentional resources to negative stimuli. Results suggested that theta and alpha oscillations activity is increased, and gamma oscillations activity is decreased during negative stimulus processing in MCI depressed individuals, thus indicating that the decreased emotion regulation in MCI depressed individuals may be associated with enhanced low-frequency and decreased high-frequency oscillations activity. Functional connectivity analysis revealed a decrease in functional connectivity in the left cerebral hemisphere of the alpha band and an increase in functional connectivity in the right cerebral hemisphere of the alpha band in MCI depressed individuals. Graph theory analysis suggested that global network metrics, including clustering coefficients and disassortative, decreased, while nodal and modular network metrics regarding local nodal efficiency, degree centrality, and betweenness centrality were significantly increased in the frontal lobe and decreased in the parieto-occipital lobe, which was observed in the alpha band, further suggesting that abnormal alpha band network connectivity may be a potential marker of depressive symptoms. Correlational analyses showed that depressive symptoms were closely related to emotion regulation, power oscillations and functional connectivity. In conclusion, the dominant processing of negative stimuli, the increased low-frequency oscillations activity and decreased high-frequency activity, so as the decrease in top-down information processing in the frontal parieto-occipital lobe, results in the abnormality of alpha-band network connectivity. It is suggested that these factors, in turn, contribute to the declined ability of MCI depressed individuals in emotion regulation.

[Distribution and Removal of Antibiotic-Resistant Bacteria and Antibiotic Resistance Genes in Petrochemical Wastewater Treatment Plants].

A petrochemical wastewater treatment plant (PWWTP) was selected to investigate the distribution and removal of antibiotic-resistant bacteria (ARB) and three forms of antibiotic resistance genes (ARGs), namely intracellular ARGs (iARGs), adsorbed-extracellular ARGs (aeARGs), and free extracellular ARGs (feARGs). Tetracycline, sulfanilamide, and ampicillin ARB were detected with the total absolute concentration of 8.45×102-2.38×105 CFU·mL-1; the absolute concentrations of three types of ARB decreased by 0.04 lg-0.21 lg through anaerobic treatment. The effect of aeration and precipitation treatment on ARB varies with its type, and the absolute concentration of ARB in effluent was 0.12 lg-0.63 lg higher than that in influent. The absolute abundance of aeARGs and iARGs in activated sludge was 1.96×107-3.02×1010 copies·g-1 and 5.22×107-4.15×1010 copies·g-1, respectively; the absolute abundance of feARGs in wastewater was 5.90×108-1.01×1012 copies·L-1. Anaerobic treatment can remove 0.13 lg-0.65 lg aeARGs and 0.04 lg-0.28 lg iARGs, while the removal efficiency of aeARGs and iARGs by aeration and precipitation process was affected by ARGs types and forms. The absolute abundance of feARGs in effluent is 0.06 lg-0.81 lg higher than that in influent. Redundancy analysis showed that the concentration of ARB was significantly positively correlated with chemical oxygen demand (COD), Cl-, and total nitrogen concentration (P<0.05). The abundance of aeARGs was positively correlated with COD and total nitrogen concentration (P<0.05), and both the abundance of iARGs and feARGs are positively correlated with heavy metals concentration (P<0.05). This study confirmed the enrichment risk of ARB and different forms of ARGs in PWWTPs, which provided references for the research and prevention of antibiotic resistance pollution in industrial wastewater.

Microbial Diversity and Community Variation in the Intestines of Layer Chickens.

The intestinal microbiota is increasingly recognized as an important component of host health, metabolism and immunity. Early gut colonizers are pivotal in the establishment of microbial community structures affecting the health and growth performance of chickens. White Lohmann layer is a common commercial breed. Therefore, this breed was selected to study the pattern of changes of microbiota with age. In this study, the duodenum, caecum and colorectum contents of white Lohmann layer chickens from same environment control farm were collected and analyzed using 16S rRNA sequencing to explore the spatial and temporal variations in intestinal microbiota. The results showed that the diversity of the microbial community structure in the duodenum, caecum and colorectum increased with age and tended to be stable when the layer chickens reached 50 days of age and the distinct succession patterns of the intestinal microbiota between the duodenum and large intestine (caecum and colorectum). On day 0, the diversity of microbes in the duodenum was higher than that in the caecum and colorectum, but the compositions of intestinal microbes were relatively similar, with facultative anaerobic Proteobacteria as the main microbes. However, the relative abundance of facultative anaerobic bacteria (Escherichia) gradually decreased and was replaced by anaerobic bacteria (Bacteroides and Ruminococcaceae). By day 50, the structure of intestinal microbes had gradually become stable, and Lactobacillus was the dominant bacteria in the duodenum (41.1%). The compositions of dominant microbes in the caecum and colorectum were more complex, but there were certain similarities. Bacteroides, Odoribacter and Clostridiales vadin BB60 group were dominant. The results of this study provide evidence that time and spatial factors are important factors affecting the intestinal microbiota composition. This study provides new knowledge of the intestinal microbiota colonization pattern of layer chickens in early life to improve the intestinal health of layer chickens.