Cystathionine gamma-lyase (Cth) induces efferocytosis in macrophages via ERK1/2 to modulate intestinal barrier repair.

BACKGROUND: The inflammatory response induced by intestinal ischaemia‒reperfusion injury (I/R) is closely associated with infectious complications and mortality in critically ill patients, and the timely and effective clearance of apoptotic cells is an important part of reducing the inflammatory response. Studies have shown that the efferocytosis by phagocytes plays an important role. Recently, studies using small intestine organoid models showed that macrophage efferocytosis could promote the repair capacity of the intestinal epithelium. However, no studies have reported efferocytosis in the repair of I/R in animal models. RESULTS: We used an in vivo efferocytosis assay and discovered that macrophage efferocytosis played an indispensable role in repairing and maintaining intestinal barrier function after I/R. In addition, the specific molecular mechanism that induced macrophage efferocytosis was Cth-ERK1/2 dependent. We found that Cth drove macrophage efferocytosis in vivo and in vitro. Overexpression/silencing Cth promoted/inhibited the ERK1/2 pathway, respectively, which in turn affected efferocytosis and mediated intestinal barrier recovery. In addition, we found that the levels of Cth and macrophage efferocytosis were positively correlated with the recovery of intestinal function in clinical patients. CONCLUSION: Cth can activate the ERK1/2 signalling pathway, induce macrophage efferocytosis, and thus promote intestinal barrier repair. Video Abstract.

Recognition of the toxicity of aristolochic acid.

WHAT IS KNOWN AND OBJECTIVE: Aristolochic acid (AA) is an abundant compound in Aristolochia plants and various natural herbs. In the 1990s, a slimming formula used in Belgium that contains Aristolochia fangchi was reported to cause kidney damage and bladder cancer, and aristolochic acid nephropathy (AAN) is now well recognized worldwide. In October 2017, researchers reported an AA signature that is closely associated with hepatocellular carcinoma (HCC) worldwide. COMMENT: There are differing opinions on the toxicity of AA, and different countries have taken different measures to address the issue. There is a lack of clarity on the causal role of AA in hepatocarcinogenesis and on the potential underlying mechanisms for the reported nephrotoxicity and carcinogenicity. The toxicity of AA differs depending on gender and age, and other risk factors that could explain the variability in the toxicity of AA remain to be identified. WHAT IS NEW AND CONCLUSION: Whether preparations containing AA, such as many Chinese medicines, should be used remains controversial, and this issue warrants further investigation before definite conclusions can be drawn.

Can Selenium and Molybdenum Restrain Cadmium Toxicity to Pollen Grains in Brassica napus?

Cadmium (Cd) is highly toxic, even at very low concentrations, to both animals and plants. Pollen is extremely sensitive to heavy metal pollutants; however, less attention has been paid to the protection of this vital part under heavy metal stress. A pot experiment was designed to investigate the effect of foliar application of Se (1 mg/L) and Mo (0.3 mg/L) either alone or in combination on their absorption, translocation, and their impact on Cd uptake and its further distribution in Brassica napus, as well as the impact of these fertilizers on the pollen grains morphology, viability, and germination rate in B. napus under Cd stress. Foliar application of either Se or Mo could counteract Cd toxicity and increase the plant biomass, while combined application of Se and Mo solutions on B. napus has no significant promotional effect on plant root and stem, but reduces the seeds' weight by 10⁻11%. Se and Mo have decreased the accumulated Cd in seeds by 6.8% and 9.7%, respectively. Microscopic studies, SEM, and pollen viability tests demonstrated that pollen grains could be negatively affected by Cd, thus disturbing the plant fertility. Se and Mo foliar application could reduce the toxic symptoms in pollen grains when the one or the other was sprayed alone on plants. In an in vitro pollen germination test, 500 µM Cd stress could strongly inhibit the pollen germination rate to less than 2.5%, however, when Se (10 µM) or Mo (1.0 µM) was added to the germination medium, the rate increased, reaching 66.2% and 39.4%, respectively. At the molecular level, Se and Mo could greatly affect the expression levels of some genes related to Cd uptake by roots (IRT1), Cd transport (HMA2 and HMA4), Cd sequestration in plant vacuoles (HMA3), and the final Cd distribution in plant tissue at the physiological level (PCS1).

[Values of ocular hemodynamics and serum endothelin-1 in the early diagnosis of diabetic retinopathy].

OBJECTIVE: To evaluate the values of ocular hemodynamics and serum endothelin-1 (ET-1) in the early diagnosis of diabetic retinopathy (DRP). METHODS: A total of 85 DRP patients were examined by ophthalmoscope and fluorescein angiography and divided into 3 groups: no obvious retinopathy (n = 20), non-proliferative diabetic retinopathy (n = 35) and proliferative diabetic retinopathy (n = 30). Control group included 15 healthy volunteers. The peak systolic velocity (PSV), end diastolic velocity (EDV) and resistance index (RI) of ophthalmic artery (OA) and central retinal artery (CRA) were measured by color Doppler energy imaging. The level of endothelin-1 was measured by radioimmunoassay. Then plasma ET-1 levels and eye vascular hemodynamic parameters were compared with correlation and diagnostic specificity after data analysis. RESULTS: Compared with the control group, DRP, EDV and PSV decreased progressively while RI increased gradually (P < 0.05). EDV and RI were more sensitive than PSV in diagnosis. The plasma level of ET-1 was significantly higher than that of control group (P < 0.05). And it was correlated positively with RI and negatively with PSV and EDV of CRA. The diagnostic value of EDV was higher than that of ET-1 level. CONCLUSION: Ocular hemodynamics become abnormal during the early stage of DRP and worsen with the progress of DRP. An elevated plasma level of ET-1 may lead to the abnormal of retinal hemodynamics. The test of plasma ET-1 and the examination of ocular hemodynamics may play an important role in the early diagnosis of DRP.

[In vivo labeling of rat neural progenitor cells in subventricular zone with superparamagnetic iron oxide for tracking of magnetic resonance imaging].

OBJECTIVE: To explore the feasibility of in vivo labeling of adult rat neural progenitor cells (NPCs) in subventricular zone (SVZ) with superparamagnetic iron oxide particles (SPIOs) for tracking of magnetic resonance imaging (MRI). METHODS: A total of 7 SD rats were stereotactically injected with 3 µl SPIOs (7 mg Fe/ml) into anterior horn of right lateral ventricle and then 5-bromo-2'-deoxyuridine (BrdU) was injected intraperitoneally once daily for 1 week. MRI was performed at 1, 3, 7 and 14 days post-injection. After the final MRI scan, all rats were transcardially perfused and their brains removed and fixed. The sections were processed for Prussian blue iron staining and Prussian blue plus BrdU immunohistochemical staining. RESULTS: In all experimental animals, SPIOs were predominantly located in the anterior horn of right lateral ventricle and partial SPIOs entered the ventricular system. A needle path and a distribution of SPIOs along rostral migratory stream (RMS) towards olfactory bulb (OB) were depicted at the sagittal view of T2(*)WI, moderate MR artifact was visible and SPIOs tracking NPCs were successful (success rate of 100%). The result of staining showed SPIOs labeling NPCs were effective. And the labeling rates were 75.5%, 42.3%, 23.6% in SVZ, RMS and OB respectively. CONCLUSION: Effective in vivo labeling of adult rat NPCs in SVZ with SPIOs is feasible. And dynamical migration of labeling NPCs along RMS towards OB may be visualized on MRI.

Integrative analysis reveals marker genes for intestinal mucosa barrier repairing in clinical patients.

This study aims to identify biomarkers of intestinal repair and provide potential therapeutic clues for improving functional recovery and prognostic performance after intestinal inflammation or injury. Here, we conducted a large-scale screening of multiple transcriptomic and scRNA-seq datasets of patients with inflammatory bowel disease (IBD), and identified 10 marker genes that potentially contribute to intestinal barrier repairing: AQP8, SULT1A1, HSD17B2, PADI2, SLC26A2, SELENBP1, FAM162A, TNNC2, ACADS, and TST. Analysis of a published scRNA-seq dataset revealed that expression of these healing markers were specific to absorptive cell types in intestinal epithelium. Furthermore, we conducted a clinical study where 11 patients underwent ileum resection demonstrating that upregulation of post-operative AQP8 and SULT1A1 expression were associated with improved recovery of bowel functions after surgery-induced intestinal injury, making them confident biomarkers of intestinal healing as well as potential prognostic markers and therapeutic targets for patients with impaired intestinal barrier functions.

Maleic acid and malonic acid reduced the pathogenicity of Sclerotinia sclerotiorum by inhibiting mycelial growth, sclerotia formation and virulence factors.

Sclerotinia sclerotiorum is a necrotrophic plant pathogenic fungus with broad distribution and host range. Bioactive compounds derived from plant extracts have been proven to be effective in controlling S. sclerotiorum. In this study, the mycelial growth of S. sclerotiorum was effectively inhibited by maleic acid, malonic acid, and their combination at a concentration of 2 mg/mL, with respective inhibition rates of 32.5%, 9.98%, and 67.6%. The treatment of detached leaves with the two acids resulted in a decrease in lesion diameters. Interestingly, maleic acid and malonic acid decreased the number of sclerotia while simultaneously increasing their weight. The two acids also disrupted the cell structure of sclerotia, leading to sheet-like electron-thin regions. On a molecular level, maleic acid reduced oxalic acid secretion, upregulated the expression of Ss-Odc2 and downregulated CWDE10, Ss-Bi1 and Ss-Ggt1. Differently, malonic acid downregulated CWDE2 and Ss-Odc1. These findings verified that maleic acid and malonic acid could effectively inhibit S. sclerotiorum, providing promising evidence for the development of an environmentally friendly biocontrol agent.

[Small-worldness of functional networks in Alzheimer's disease].

OBJECTIVE: To construct the functional networks of human brains by resting-state functional magnetic resonance imaging (fMRI) and examine whether or not the small-world property of functional brain networks changes in patients with Alzheimer disease (AD). METHODS: A total of 33 AD patients and 20 healthy old volunteers were recruited. Their cognitive functions were evaluated by the mini-mental state examination (MMSE) and Mattis dementia rating scale (DRS). The resting-state BOLD-fMRI data were acquired and preprocessed. Then the correlation coefficient of every pair of 90 regions was calculated and correlation matrix Z (N×N, N = 90) generated by Fisher Z transformation. The small-world property of functional brain networks was tested for AD patients and normal elders according to the definition of small-worldness. The changes of relevant parameters in AD patients were examined by two sample t-tests. RESULTS: Behavioral results: the MMSE scores of AD group and normal controls (NOR) were 20.60 ± 2.30 and 28.20 ± 1.80 respectively. The DRS scores of AD and NOR groups were 96.00 ± 10.82 and 123.22 ± 13.74 respectively. The MMSE and DRS scores were statistically different between two groups. Calculation of small-world parameters: Within the range of 0.1 ≤ Sparsity ≤ 0.4, both groups satisfied the small-world property. However, the clustering coefficient Cp and the average shortest path Lp of AD group were significantly higher than those of NOR group at each threshold (P < 0.05). CONCLUSIONS: The functional brain networks in AD patients still have the property of small-world. But the levels of Cp and Lp are higher in AD patients than those in normal controls. It suggests that the capacity of information transmission in functional brain networks and the ability of information integration in different brain regions in AD patients are impaired. This finding is of great importance in elucidating the pathological mechanisms of AD from the viewpoint of networks.

[Central mechanism of electric-acupuncture at Zusanli (ST36) for gastric mucous membrane protection with FMRI].

OBJECTIVE: To explore the central mechanism of acupuncture in protecting gastric mucous membrane by a composite analysis of gastric mucous membrane related indices in peripheral blood and functional MRI (fMRI) signal changes after electric-acupuncturing Zusanli (ST36) acupoint. METHODS: Sixteen healthy adult volunteers were divided into true acupoint group (A) and sham acupoint group (B). Zusanli acupoint was used for Group A. Peripheral blood was drawn 5 min before and 5, 15, 25, 30 min after needle-removal for the detection of gastric mucous membrane related indices. fMRI was performed during acupuncture and the acquired fMRI data were analyzed by SPM2 (P < 0.001). RESULTS: The levels of calcitonin gene related peptide (CGRP) and prostaglandin E2 (PGE2) increased while those of endothelin (ET) and gastrin (GAS) decreased significantly after acupuncture in Group A (P < 0.01). And there was no significant change in Group B (P > 0.05). Acupuncturing Zusanli activated the bilateral middle frontal gyrus, caudate, left precentral and postcentral gyri, hypothalamus, anterior cingulate cortex, right hippocampus, insula and cerebellar hemisphere. But acupuncturing the sham acupoint only activated the paracentral lobule and cerebellar hemisphere. CONCLUSION: Acupuncturing Zusanli acupoint activates certain cortex areas and multiple systems to stimulate the release of neurotransmitters and regulate the peripheral humoral factors to achieve the protection of gastric mucous membrane.

Risk factors for postpartum depression: An evidence-based systematic review of systematic reviews and meta-analyses.

PURPOSE: Postpartum depression (PPD) is the most common psychiatric condition after childbirth which not only effects the mother's health, but also might have impact on child's development and parenting behaviors. Because the etiology of PPD has not been fully cleared, the efforts towards identification of risk factors are crucial for both the children and mother's health. METHOD: PubMed, EMBASE and PsycINFO databases were searched since inception until July 2019 to collect data about the risk factors of PPD and only systematic review and meta-analysis can be included. RESULT: To identify the real risk factors, protective factors and controversial factors, nineteen parts of the interpretation were adopted. The risk factors are mainly concentrated in the following aspects: violence and abuse, immigration status, gestational diabetes, cesarean section, depressive history, vitamin D deficiency, obese and overweight, postpartum sleep disruption and poor postpartum sleep, lack of social support, traditional dietary pattern (Japanese, Indian, United Kingdom, and Brazilian dietary pattern), multiple births, preterm and low-birth-weight infants, postpartum anemia, negative birth experience. The controversial factors are serum level of cortisol, thyroid peroxidase autoantibodies status, acculturation, traditional confinement practices. Skin-to-skin care, higher concentrations of DHA in mothers' milk, greater seafood consumption, healthy dietary patterns, multivitamin supplementation, fish and PUFA intake, calcium, Vitamin D, zinc and possibly selenium are protective factors. CONCLUSION: Thirteen risk factors were identified, but five factors still controversial due to the insufficient of the evidence. What's more, skin-to-skin care and some nutrition related factors are protective factors against PPD.

Heterogeneity of nutrition care procedures in nutrition guidelines for cancer patients.

OBJECTIVES: The aim of this study was to systematically assess the nutrition care procedures in nutrition guidelines for cancer patients and identify gaps limiting evidence-based practise. METHODS: A systematic search of databases and websites was conducted to identify nutrition guidelines for cancer patients. The quality of the eligible guidelines was evaluated by using the Appraisal of Guidelines for Research and Evaluation (AGREE II). The Measurement Scale of Rate of Agreement (MSRA) was used to assess the scientific agreement of formulated recommendations for nutrition care procedures in the guidelines (2017-2019), and evidence supporting these recommendations was extracted and analysed. RESULTS: Seventeen nutrition guidelines for cancer patients were identified. Only European Society for Clinical Nutrition and Metabolism (ESPEN) and Australian guidelines have a total quality score of more than 60%, which is worthy of clinical recommendation. Twelve guidelines (2017-2019) were included to further analyse the heterogeneity and causes of nutrition care procedures, and we found that the content and tools of nutrition screening and assessment, the application of immune nutrients, and the selection of nutritional support pathways were heterogeneous. The main reasons for the heterogeneity of nutrition care procedures were insufficient attention to nutrition risk screening, differences in recommendations for nutrition assessment, immune nutrients and nutritional support, unreasonable citation of screening and assessment evidence, preference of developers, and lack of evidence of high-quality research on energy and nitrogen demand. In addition, the fairness and propensity of the guidelines for the selection of evidence for different cancer patients are also potential reasons for the heterogeneity of nutritional care procedures. CONCLUSIONS: The quality of the nutrition guidelines for cancer patients was highly variable. The nutrition care procedures were heterogeneous among the different guidelines in the last 3 years. Specific improvement of the factors leading to the heterogeneity of nutrition care procedures will be a reasonable and effective way for developers to upgrade the nutrition care procedures in the guidelines for cancer patients.

[Effects of mesenchymal stem cell transplantation on growth of liver cancer: experiment with rats].

OBJECTIVE: To evaluate the effects of mesenchymal stem cell (MSC) transplantation on the growth of liver cancer. METHODS: MSCs were isolated from the bone marrows of SD rats. Walker-256 cancer cells were isolated from the cancerous ascites of rat and cultured. Forty-five SD rats were randomly divided into 3 equal groups: mixed transplantation group undergoing laparotomy and transplantation of cancer cells mixed with MSCs into the liver, MSC IV transplantation group undergoing injection of MSCs into the caudal vein, and control group undergoing only MSC transplantation into the liver. MR imaging was performed s at days 3, 6, 9 and 12 after modeling to measure the maximum cross section area of the tumor. At day 12 the rats were killed after MR imaging with their livers taken out to undergo HE staining and pathological examination. Immunohistochemistry was used to detect the expression of vascular endothelial cell growth factors (VEGF), nm23 gene, a tumor metastasis inhibiting gene, and proliferating cell nuclear antigen (PCNA), a nuclear polypeptide necessary in the DNA synthesis. RESULTS: No significant evidence of tumor formation was detected by MRI at days 3 and 6 after modeling in all rats and tumor nodules were observed since day 9. The maximum cross section areas of tumor of the mixed transplantation group and MSC IV transplantation group were significantly larger than that of the control group at days 9 and 12 (F = 4.21, P < 0.05; F = 8.52, P < 0.01). Immunohistochemistry showed that VEGF expression levels of the two study groups were both significantly higher than that of the control group (F = 9.58, P < 0.01), while the nm23 gene expression levels of the 2 study groups were both significantly lower than that of the control group (F = 4.61, P < 0.05). The PCNA expression level of the mixed transplantation group was significantly higher than that of the control group (d'((1, 0.05)) = 0.34, d'((1, 0.01)) = 0.63, P < 0.05), however, there was no significant difference in the PCNA expression level between the MSCs IV transplantation group and the control group (d'((1, 0.05)) = 0.32, d'((1, 0.01)) = 0.48, P > 0.05). There was no significant difference in the tumor apoptotic index between the 2 study groups and the control group (F = 1.25, P > 0.05). CONCLUSION: MSC transplantation increases the expression of VEGF and PCNA, while decreases the expression of nm23 gene in cancer cells, thus favoring the tumor growth.

Sample entropy and surrogate data analysis for Alzheimer's disease.

Alzheimer's disease (AD) is a neurological degenerative disease, which is mainly char-acterized by the memory loss. As electroencephalogram (EEG) device is relatively cheap, portable and non-invasive, it has been widely used in AD-related studies. We proposed a method to detect the differences between healthy subjects and AD patients, which combines classical sample entropy (Sam-pEn) and surrogate data method. EEGs from 14 AD patients and 20 healthy subjects were analyzed. The results based on the original data showed that the SampEn of AD patients was significantly de-creased (p < 0.01) at electrodes c3, f3, o2 and p4, which confirmed that AD could cause complexity loss. However, using original data could be subject to human judgement, so we generated a series of surrogate data. We found that, there were significant difference of SampEn between the original time series and their surrogate data at c3 and o2 electrodes and the differences between healthy subjects and AD patients can be verified. Our method is capable of distinguishing AD patients from healthy subjects, which is consistent with the concept of physiologic complexity, and providing insights for understanding of AD.

[Anxiety disease: decreased of functional connectivity in left superior temporal gyrus (GTs) and right GTs].

OBJECTIVE: Neuronal circuits involved in the pathophysiology of anxiety are not yet fully understood. We used functional connectivity MRI to explore the characteristic of functional connectivity in anxiety disorders patient and the neural mechanism of this disease. This work was selected as an oral presentation in 2006 ISMRM. METHODS: Twenty right-handed subjects were included in this study, and were divided into two groups. The anxiety (P) group (n = 10; 7 male, mean age 42 years) consisted of patients meeting DSM-IV criteria for a principal diagnosis of anxiety disorder. The control (C) group consisted of volunteers free of psychiatric symptoms, and was matched on age and gender (n = 10; 7 male) with the panic patients. The subjects underwent noninvasive functional magnetic resonance imaging while listening actively to (1): emotionally neutral word alternating with no word as the control condition (CN, PN), and (2): threat-related words alternating with emotionally neutral word as the experimental condition (CT, PT). Each word was presented in pseudorandom order in each 16 s block of 12 words of the same type. Eight alternating blocks of neutral words were presented for about 256 s. The subject was only asked to passively listen to each word. All MRI data were obtained on a 1.5-Tesla scanner Data analysis was performed with SPM99 to find significant activations in two tasks for two groups. Based on group t-test, we chose two anatomically defined regions: left superior temporal gyrus (GTs) and right GTs. Then, based on individual t-map, the voxel with the largest t-value within two regions was taken as the subject-specific peak voxel. We define clusters based on faces and edges, but not corners, so each voxel has 18 neighbors. Subject-specific averaged time series were extracted by averaging the time series of 19 voxels. Since healthy control subjects showed no significant activation (corrected, P < 0.05) during processing of anxiety word to neutral word, region of interest during processing of neutral word to no word was used as substitution. The connectivity degree eta(i j) between the node i and the node j is used to identify the change of the functional connectivity associated with differential tasks, which calculated by using the methods that have developed by ourselves. Moreover, we just consider coherence in low-frequency (0-0.15 Hz). RESULTS: The activation brain regions have been reported in our previous work. Patients were significant different from normal controls on two experiments. The connectivity degree of left Gts and right Gts in two tasks across all subjects was calculated. Comparing during processing neutral word to blank, a significant decrease (P < 0.001) in functional degree was observed during processing of threaten word to neutral word (eta = 0.5636 for CN, eta = 0.555 for CT, eta = 0.5616 for PN, eta = 0.4926 for PT). Especially, the greater decrease connectivity degree was identified for patient group compared with normal control during threat-related words alternating with emotionally neutral word condition. The connectivity degree identifies that functional interactions change with differential task. CONCLUSION: This result suggests decreased functional connectivity among left superior temporal gyrus and right GTs during processing of anxiety word to neutral word in anxiety patients. This dysfunction may mediate the neural mechanism of this sort of disease.

[CT and pathological manifestations of intraductal papillary mucinous neoplasm of pancreas: a comparative study].

OBJECTIVE: To evaluate the diagnostic value of CT in pancreas intraductal papillary mucinous neoplasm (IPMN) by analyzing its CT feature and pathological findings. METHODS: The clinical and CT data was analyzed among 39 patients with IPMN whose diagnosis was confirmed by pathology. The CT manifestations were classified into 3 types: simple main pancreatic duct enlargement; main pancreatic duct enlargement combined with pancreatic cystic lesion; and simple pancreatic cystic lesion. The correlation between the CT types and Takada pathological types (main duct type, branch type, and mixed type) was analyzed. All the cases were pathologically classified into benign and malignant/boundary groups. Statistical tests of the difference of CT features (mural nodule, septa, size, caliber of main pancreatic duct and common bile duct) between the 2 groups were performed. RESULTS: The CT type I matched the main duct type, the CT type II mainly matched the branch type and mixed type, and the CT type III matched the branch type (P < 0.001). The probability of benign lesion was 92% with no mural nodule in the lesion, while the probability of benign lesion was only 42% with mural nodule presented (P = 0.003). In terms of the septa, there was no significant difference between benign and malignant lesions (P = 0.793). The size of malignant/boundary lesions exceeded that of benign lesions (P = 0.016). There were no significant difference in calibers of main pancreatic duct and common bile duct between the benign and malignant/ boundary groups. Without considering pathological grouping the caliber of main pancreatic duct exceeded that of the common bile duct in all the cases (P = 0.02). CONCLUSION: CT typing of IPMN well matches the pathological typing which benefits the CT diagnosis of IPMN. The caliber of main pancreatic duct usually exceeds that of common bile duct in IPMN. This feature contributes to its diagnosis.

[Effects of Wastewater Nitrogen Concentrations and NH4+/NO3- on Nitrogen Removal Ability and the Nitrogen Component of Myriophyllum aquaticum (Vell.) Verdc].

Solution culture experiments were conducted to investigate the effect of wastewater nitrogen levels and NH4+/NO3- on nitrogen removal ability and the nitrogen component of Myriophyllum aquaticum. Experiments with three nitrogen levels and NH4+/NO3- were set up as follows:20, 100, and 200 mg·L-1and NH4+/NO3- 1:0, 0.5:0.5, and 0:1. The results showed that the biomass of plants increased fastest during the first week. The plants treated with NH4+/NO3-=1:0 with nitrogen levels of 20 and 100 mg·L-1 and those treated with NH4+/NO3-=0.5:0.5 with a nitrogen concentration of 200 mg·L-1 exhibited higher biomass than the others. The removal rates of water total nitrogen, ammonium nitrogen, and nitrate nitrogen during the first week were the maximum for all treatments and increased with water nitrogen levels. There were no significant differences in the removal rate between ammonium nitrogen and nitrate nitrogen with a nitrogen level of 20 mg/L, while with nitrogen levels of 100 and 200 mg·L-1, the nitrate removal rates were higher than those for ammonium nitrogen. The Myriophyllum aquaticum nitrogen accumulation and its contribution rate to nitrogen removal from water and sediment were all increased with water nitrogen levels and increased fastest during the first week. The contribution rate of nitrogen accumulated by plants with NH4+/NO3-=0:1 was the highest with nitrogen levels of 20 mg·L-1, while plants with NH4+/NO3-=0.5:0.5 were the highest with nitrogen levels of 100 and 200 mg·L-1. The protein, amino, and nitrate nitrogen contents in Myriophyllum aquaticum plants were all increased by increasing water nitrogen levels with a ranking of protein content > amino nitrogen content > nitrate nitrogen content. The protein concentrations in plants with NH4+/NO3-=1:0 and NH4+/NO3-=0.5:0.5 were higher regardless of water nitrogen levels, while the amino nitrogen concentration in plants with NH4+/NO3-=1:0 and the nitrate nitrogen content in plants with NH4+/NO3-=0:1 were higher than the others. It was concluded that the nitrogen removal ability of Myriophyllum aquaticum was improved by raising water nitrogen levels under the tested condition, which indicates that Myriophyllum aquaticum could purify high nitrogen wastewater. Myriophyllum aquaticum is an ammonium-nitrophile, but had the strongest capacity for growing and removing wastewater nitrogen exhibited with higher than 100 mg·L-1 nitrogen levels only with equal NH4+ to NO3-. The nitrogen component concentrations of protein, amino, and nitrate in Myriophyllum aquaticum plant were all affected by the ratio of NH4+/NO3-.

Altered default mode network activity in patient with anxiety disorders: an fMRI study.

Anxiety disorder, a common mental disorder in our clinical practice, is characterized by unprovoked anxiety. Medial prefrontal cortex (MPFC) and posterior cingulate cortex (PCC), which closely involved in emotional processing, are critical regions in the default mode network. We used functional magnetic resonance imaging (fMRI) to investigate whether default mode network activity is altered in patients with anxiety disorder. Ten anxiety patients and 10 healthy controls underwent fMRI while listening to emotionally neutral words alternating with rest (Experiment 1) and threat-related words alternating with emotionally neutral words (Experiment 2). In Experiment 1, regions of deactivation were observed in patients and controls. In Experiment 2, regions of deactivation were observed only in patients. The observed deactivation patterns in the two experiments, which included MPFC, PCC, and inferior parietal cortex, were similar and consistent with the default model network. Less deactivation in MPFC and greater deactivation in PCC were observed for patients group comparing to controls in Experiment 1. Our observations suggest that the default model network is altered in anxiety patients and dysfunction in MPFC and PCC may play an important role in anxiety psychopathology.

[Assessment of preclinical cognition impairment in hypertension patients with functional magnetic resonance imaging].

OBJECTIVE: To explore whether the hypertension patients with no clinical cognitive impairment manifestations have certain brain dysfunctions. METHODS: Twenty-five moderately to severely hypertensive patients, males and females, aged 63.0 +/- 1.6 (60 approximately 65), with a disease history if 5 to 10 years, and 25 sex, age, and educational level-matched healthy persons underwent tests by mini-mental status examination (MMSE) scales, state anxiety inventory (STAI-S) and trait anxiety inventory (STAI-T), and then underwent two functional magnetic resonance imaging (fMRI) studies. In Experiment 1, the subjects were demanded to listen actively to the meaningless words (pseudowords) and in Experiment 2 the subjects listened actively to real words and make the valence (abstract or concrete) of the words in silence. The subjects were told to listen passively the noise from the MR scanners during the resting period, which was used as the control task. The fMRI data were analyzed with statistical parametric mapping (SPM99) software. RESULTS: The MMSE score of the patient group was 29.3 +/- 1.1, not significantly different from that of the control group (29.6 +/- 0.5, P > 0.05). The STAI-S score of the patient group was 47 +/- 5.3748, significantly higher than that of the control group (41.6 +/- 4.9777, P < 0.05). The STAI-S score of the patient group was 45 +/- 3, not significantly different from that of the control group (43 +/- 4, t = 1.0619, P = 0.3032). In Experiment 1, the activated patterns and deactivated patterns were nearly similar for the patient and control groups. The activated regions included the bilateral superior temporal lobe, bilateral inferior frontal cortex and supplementary motor areas. In Experiment 2, the activated patterns were also nearly similar for these 2 groups. The regions included the bilateral superior temporal lobe, bilateral inferior frontal cortex, left angular gyrus, bilateral superior frontal cortex, bilateral cerebellum, premotor areas, and supplementary motor areas. The deactivation patterns were similar for the patients and controls both in Experiment 1 and Experiment 2. These regions were medial prefrontal cortex, posterior cingulate and bilateral inferior parietal cortex, which nearly overlapping with the default model network proposed by Raichle et al. However, the activation and deactivation magnitude and extent of the brain were significantly greater for the patients than for the controls both in Experiment 1 and Experiment 2. CONCLUSION: Some brain dysfunction may have already existed in patients with moderately to severely hypertension disorders, though their behavior performance scores are within the normal range of ages. The fMRI technique can be a useful tool to detect the preclinical brain abnormalities.

Uptake, transport and distribution of molybdenum in two oilseed rape (Brassica napus L.) cultivars under different nitrate/ammonium ratios.

OBJECTIVES: To investigate the effects of different nitrate sources on the uptake, transport, and distribution of molybdenum (Mo) between two oilseed rape (Brassica napus L.) cultivars, L0917 and ZS11. METHODS: A hydroponic culture experiment was conducted with four nitrate/ammonium (NO3-:NH4+) ratios (14:1, 9:6, 7.5:7.5, and 1:14) at a constant nitrogen concentration of 15 mmol/L. We examined Mo concentrations in roots, shoots, xylem and phloem sap, and subcellular fractions of leaves to contrast Mo uptake, transport, and subcellular distribution between ZS11 and L0917. RESULTS: Both the cultivars showed maximum biomass and Mo accumulation at the 7.5:7.5 ratio of NO3-:NH4+ while those were decreased by the 14:1 and 1:14 treatments. However, the percentages of root Mo (14.8% and 15.0% for L0917 and ZS11, respectively) were low under the 7.5:7.5 treatment, suggesting that the equal NO3-:NH4+ ratio promoted Mo transportation from root to shoot. The xylem sap Mo concentration and phloem sap Mo accumulation of L0917 were lower than those of ZS11 under the 1:14 treatment, which suggests that higher NO3-:NH4+ ratio was more beneficial for L0917. On the contrary, a lower NO3-:NH4+ ratio was more beneficial for ZS11 to transport and remobilize Mo. Furthermore, the Mo concentrations of both the cultivars' leaf organelles were increased but the Mo accumulations of the cell wall and soluble fraction were reduced significantly under the 14:1 treatment, meaning that more Mo was accumulated in organelles under the highest NO3-:NH4+ ratio. CONCLUSIONS: This investigation demonstrated that the capacities of Mo absorption, transportation and subcellular distribution play an important role in genotype-dependent differences in Mo accumulation under low or high NO3-:NH4+ ratio conditions.

[Effect of Wastewater Nitrogen Concentrations on Nitrogen Removal Ability of Myriophyllum aquaticum].

Myriophyllum aquaticum, which is an important plant for constructed wetlands, has powerful purification ability for wastewater, however, the relationship between nitrogen removal ability of Myriophyllum aquaticum and wastewater nitrogen concentrations is still unclear. In this study, pot culture experiment was conducted to investigate the effect of wastewater nitrogen levels on nitrogen removal ability of Myriophyllum aquaticum. 7 nitrogen levels were set up as following:2, 5, 10, 20, 100, 200, 400 mg·L-1. The results showed that when the wastewater nitrogen concentration was not higher than 20 mg·L-1, Myriophyllum aquaticum with 20 mg·L-1 of nitrogen concentration grew best in the first 3 weeks; the removal rates of total and ammonia nitrogen were nearly 100% after one week, while the nitrate nitrogen concentrations were very low and varied little; the nitrogen contents of Myriophyllum aquaticum had no significant change, the upper part nitrogen content was higher than the underneath, Myriophyllum aquaticum could also remove nitrogen from the sediment. When wastewater nitrogen concentrations were 100-400 mg·L-1, Myriophyllum aquaticum with 200 mg·L-1 of nitrogen concentration grew best from 4th to 5th week; the removal rates of total nitrogen were 76.5%, 71.5% and 48.1% in the three treatments, and the removal rates of ammonia nitrogen were 99.6%, 99.3% and 60.2% respectively, while the removal rates of nitrate nitrogen were all about 50% and there was no significant difference among treatments; the nitrogen contents of Myriophyllum aquaticum increased with nitrogen levels, but the difference between upper part and underneath was not remarkable, showing uniform distribution; nitrogen accumulations by Myriophyllum aquaticum and sediment accounted for 27.9%-48.4% and 12.2%-24.4% of total nitrogen loss in wastewater. Therefore, the nitrogen removal ability of Myriophyllum aquaticum should be inhibited by higher wastewater nitrogen level, the ammonia nitrogen removal rate was significantly higher than nitrate, the mechanism of Myriophyllum aquaticum nitrogen accumulation and distribution should also be affected by wastewater nitrogen level, and further research is needed.