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Antibiotics are designed to affect gut microbiota and subsequently gut homeostasis. However, limited information exists about short- and long-term effects of early antibiotic intervention (EAI) on gut homeostasis (especially for the small intestine) of pigs following antibiotic withdrawal. We investigated the impact of EAI on specific bacterial communities, microbial metabolites and mucosal immune parameters in the small intestine of later-growth-stage pigs fed with diets differing in CP levels. Eighteen litters of piglets were fed creep feed with or without antibiotics from day 7 to day 42. At day 42, pigs within each group were offered a normal- or low-CP diet. Five pigs per group were slaughtered at days 77 and 120. At day 77, EAI increased Enterobacteriaceae counts in the jejunum and ileum and decreased Bifidobacterium counts in the jejunum and ileum (P < 0.05). Moreover, tryptamine, putrescine, secretory immunoglobulin (Ig) A and IgG concentrations in the ileum and interleukin-10 (IL-10) mRNA and protein levels in the jejunum and ileum were decreased in pigs with EAI (P < 0.05). At day 120, EAI only suppressed Clostridium cluster XIVa counts in the jejunum and ileum (P < 0.05). These results suggest that EAI has a short-term effect on specific bacterial communities, amino acid decarboxylation and mucosal immune parameters in the small intestine (particularly in the ileum). At days 77 and 120, feeding a low-CP diet affected Bifidobacterium, Clostridium cluster IV, Clostridium cluster XIVa and Enterobacteriaceae counts in the jejunum or ileum (P < 0.05). Moreover, feeding a low-CP diet increased the concentrations of Igs in the jejunum and decreased pro-inflammatory cytokines levels in the jejunum and ileum (P < 0.05). At day 120, feeding a low-CP diet increased short-chain fatty acid concentrations, reduced ammonia and spermidine concentrations and up-regulated genes related to barrier function in the jejunum and ileum (P < 0.05). These results suggest that feeding a low-CP diet changes specific bacterial communities and intestinal metabolite concentrations and modifies mucosal immune parameters. These findings contribute to our understanding on the duration of the impact of EAI on gut homeostasis and may provide basis data for nutritional modification in young pigs after antibiotic treatment.
Flexibility is one of the important mechanical performance parameters of stent. The flexibility of tapered stents, especially self-expanding tapered stents, remains unknown. In this study, we developed a new selfexpanding tapered stent for tapered arteries and performed a numerical investigation of stent flexibility by using finite element method. The effect of stent design parameters, including taper and link space width, on stent flexibility was studied. The flexibility of the proposed stent was also compared with that of traditional cylindrical stents. Results show that the tapered stent is more flexible than the traditional cylindrical stent. Furthermore, the flexibility of the tapered stent increases with increasing stent taper and stent link space width. The increase in the stent link space width can contribute to the reduction in the peak stress. Therefore, tapered stents with high link space width will improve the stent flexibility. This work provides useful information for improvement of stent design and clinical selection.
Studies revealed that prenatal stress (PS) may increase the vulnerability to depression in their offspring, and ERK-CREB signal system might play a role in its mechanism.
Objectives and aims
The present study investigated the effect of MK-801 on depressive-like behavior and its impacts on ERK2, CREB, Bcl-2 mRNA expression in PS female rat offspring.
The pregnant rats were randomly divided into three groups, the control group (Con) was left undisturbed, the PS-saline group (PS-saline) and the PS-MK-801 group (PS-MK-801) were subjected to restraint stress on days 14–20 of pregnancy three times daily for 45 min, and received an i.p. administration of saline or MK-801(sigma, 0.2 mg/kg) 30 min before the first stress respectively. Forced swimming test was undertaken to assess depressive-like behavior in one month female offspring. ERK2, CREB, Bcl-2 mRNA in the hippocampus, frontal cortex, and striatum were detected by RT-PCR.
PS-saline spent significantly more immobile time compared to Con and PS-MK-801 (P < 0.05). ERK2 and CREB mRNA expression in hippocampus and frontal cortex was significantly decreased in PS-saline compared to Con and PS-MK-801 (P < 0.05), while in striatum CREB mRNA expression in PS-saline was lower than Con (P < 0.05). Bcl-2 mRNA expression in hippocampus and striatum was significantly decreased in PS-saline (P < 0.05), and in frontal cortex, its expression was significantly lower in PS-saline and PS-MK-801 (P < 0.05).
PS may suppress ERK-CREB signal pathway in female offspring rats, which could be partly prevented by MK- 801. (Supported by National Natural Science Foundation of China, No: 30970952).
Studies have convinced that the rodents' exposure to prenatal stress (PNS) may induce depression and anxiety to their offspring. We focused on the glutamatergic system to explore the mechanisms.
Objectives and aims:
By examining EAAT2,EAAT3 (Excitatory Amino Acid Transporter 2,3), which are the only substances to inactivate glutamate in nervous system, we explored the effect of PNS on glutamatergic system.
Pregnant rats were assigned to Control group (CON), Middle period of PNS group (MPS) and Late period of PNS group (LPS). MPS and LPS rats were exposed to restraint stress on days 7–13, 14–20 of pregnancy three times daily for 45 min. EAAT2 and EAAT3 mRNA expression in the hippocampus, frontal cortex, and striatum of one month rat offspring were checked by RT-PCR.
For the female offspring, EAAT2 mRNA expression of hippocampus in LPS and MPS was significantly lower compared to CON(P = 0.008,p = 0.003); EAAT2 and EAAT3 mRNA expression of frontal cortex in LPS were significantly lower than CON (p = 0.003,p = 0.013). for the male offspring, EAAT2 and EAAT3 mRNA expression of hippocampus in LPS and MPS were significantly lower (p = 0.005, p = 0.05); EAAT2 mRNA expression of frontal cortex was significantly lower in LPS (p = 0.022); EAAT2 mRNA in LPS group and MPS were significantly lower (p = 0.009, p = 0.014), and EAAT3 mRNA expression of striatum in MPS was significantly lower (p = 0.049).
Decreased EAAT2 and EAAT3 of PNS may explain the increase of glutamate in synaptic cleft and its downstream excitotoxicity. (Supported by National Natural Science Foundation of China, No: 30970952)
A continuum perspective to understand persecutory delusions suggests that non-clinical persecutory ideations are at the mild end on the same spectrum of persecutory delusions. Based on clinical studies, reasoning biases such as 'jumping to conclusions' (JTC) style, attributional biases (AB), and Theory of Mind (ToM) deficit have been suggested as cognitive risk factors of persecutory delusions, with most robust evidence for JTC. Consistent with the continuum perspective, it is of interest whether these reasoning biases are risk factors of persecutory ideations in the non-clinical population as well.
To examine the association between JTC, AB, ToM deficit, and persecutory ideations in non-clinical populations.
To test the following hypotheses:
1. JTC, AB, and ToM deficit will be found in individuals with non-clinical persecutory ideations.
2. Among the three biases, JTC will be more strongly associated with the severity of persecutory ideations in the non-clinical population.
Twenty studies from 2001 to 2013 analyzing the relationship between reasoning biases and severity of persecutory ideations in non-clinical populations were systematically reviewed.
JTC, AB and ToM deficit were found in individuals with non-clinical persecutory thinking but at reduced levels of severity as compared to the clinical populations. A consistent association between JTC and non-clinical persecutory thinking was found across studies. However, studies of AB and ToM deficit yielded conflicting findings.
Current findings confirm the role of JTC in the pathogenesis of persecutory delusions, and support the development of early interventions targeting data-gathering for individuals at risk of developing persecutory delusions.
Epidemiological studies have convinced that prenatal stress (PS) might cause offspring depression.
Objectives and aims:
Our pervious research work certified that PS can increases the glutamate level of hippocampus of rat offspring, which inspired us to explore the pathogenesis of depression by focusing on glutamatergic system.
Pregnant rats were randomly assigned to control group (CON), mid prenatal stress group (MPS) and late prenatal stress group (LPS). The pregnant rats of MPS and LPS were exposed to restraint stress on days 7–13, 14–20 of pregnancy three times for 45 min respectively. Tail suspension test (TST) was performed to examine the depression like behavior and Western-blot were used to test phosphorylated GluR1(pGluR1) of AMPAR expression in the hippocampus, striatum and frontal cortex of one month rat offspring.
For both male and female offspring, the time of immobility of TST in LPS (156±11, 155±12) and MPS (173±15, 155±12) was significantly longer (P< 0.05) than CON(118±8,113±12), the latency in MPS (18±3, 24±3) was significantly shorter (P< 0.05) than CON (30±5, 58±11). The pGluR1 expression in hippocampus and frontal cortex in LPS (1.77±0.45, 1.00±0.09) and MPS (1.65±0.51, 1.05±0.18) were significantly lower (P< 0.05) than CON (3.72±0.86, 2.05±0.34) in male rat offspring.
It is suggested that the PS may induce depression like behavior in rat offspring, and glutamate receptors subunit pGluR1 might be involved in the etiology of depression.
(The research is supported by National Natural Science Foundation of China, No: 30970952, 18110059).
It is assumed that dysfunctional meta-cognitive beliefs about one's thoughts increase problematic appraisals and coping behaviors, which further contribute to the development of mental disorders (Wells and Matthews, 1994; Wells, 2000). Although this research interest originated around generalized anxiety disorder (GAD), recent studies have begun to examine similar meta-cognitive processes in other disorders. The majority of studies using Meta-cognitions Questionnaire (MCQ; Cartwright-Hatton & Wells, 1997) and its variants to assess meta-cognitive beliefs.
We conducted a meta-analysis to integrate empirical findings on group differences in meta-cognitive beliefs between healthy individuals and patients with various psychiatric disorders.
We followed the PRISMA guideline (Liberati et al., 2009). A systematic literature search was conducted. We included studies that involved a diagnosed psychiatric group and healthy controls (aged 18 or above), reported group comparisons of metacognition, and were published during the period of 1990–27 August 2015. Effect sizes were computed.
A final set of 43 studies was included. Large combined effect sizes were found on each subdomain of the MCQ, indicating increased levels of dysfunctional meta-cognitive beliefs in patients. Subgroup analyses were carried out based on psychiatric diagnosis (i.e. psychosis, n = 10; GAD, n = 7; obsessive-compulsive disorder, OCD, n = 15; anorexia nervosa, n = 5). All patient groups were more dysfunctional on each subtype of meta-cognitive beliefs than controls. Effect size of U/D was particularly large for GAD, and that of CSC was particularly large for OCD.
Dysfunctional meta-cognitive beliefs are evident across several psychiatric disorders, with specific types of beliefs being more marked in certain diagnoses.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Childhoods in urban or rural environments may differentially affect risk for neuropsychiatric disorders. Here, we leveraged on dramatic urbanization and rural-urban migration since the 1980s in China to explore the hypothesis that rural or urban childhoods may differentially influence memory processing and neural responses to neutral and aversive stimuli.
Explore the underlying mechanisms of childhood environment effect on brain function and neuropsychiatric risk.
We examined 420 adult subjects with similar current socioeconomic status and living in Beijing, China, but with differing rural (n = 227) or urban (n = 193) childhoods. In an episodic memory paradigm scanned in a 3 T GE MRI, subjects viewed blocks of neutral or aversive pictures in the encoding and retrieval sessions.
Episodic memory accuracy for neutral stimuli was less than for aversive stimuli (P < 0.001). However, subjects with rural childhoods apparently performed less accurately for memory of aversive but not neutral stimuli (P < 0.01). In subjects with rural childhoods, there was relatively increased engagement of bilateral striatum at encoding, increased engagement of bilateral hippocampus at retrieval of neutral and aversive stimuli, and increased engagement of amygdala at aversive retrieval (P < 0.05 FDR corrected, cluster size > 50).
Rural or urban childhoods appear associated with physiological and behavioural differences, particularly in the neural processing of aversive episodic memory at medial temporal and striatal brain regions. It remains to be explored the extent to which these effects relate to individual risk for neuropsychiatric or stress-related disorders.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Dysfunctions in metacognition have been reported in individuals with anxiety disorders. Although recent studies have examined metacognition in other disorders, how dysfunctional metacognition compares across disorders is not clear. This review aimed to ascertain the importance of dysfunctional metacognition in various psychopathologies, and to identify similarities and differences in metacognitive profiles across disorders.
Forty-seven studies were selected from 586 articles published between 1990 and August 2015, including a total sample of 3772 patients and 3376 healthy individuals. Studies that measured metacognition using the Meta-Cognitions Questionnaire (MCQ) and its variants were included. We conducted five meta-analyses including 49 to 55 effect sizes, comparing psychiatric patients to healthy individuals on respective metacognitive dimensions of the MCQ.
We found elevated metacognitive dysfunctions in patients, as a group, on all MCQ dimensions. Group effects were large and robust for the two negative beliefs (i.e., beliefs about the uncontrollability and danger of thoughts, and beliefs about the need to control thoughts), and moderate and unstable for the positive beliefs. Patients showed decreased cognitive confidence and heightened cognitive self-consciousness on moderate to large levels. Moderator analyses revealed that negative beliefs about uncontrollability and danger of thoughts were most prevalent in generalized anxiety disorder, whereas heightened cognitive self-consciousness was more characteristic in obsessive-compulsive disorder. Generalized anxiety disorder, obsessive-compulsive disorder and eating disorders manifested more similar metacognitive profiles than other disorders.
Our findings supported dysfunctional metacognition as common processes across psychopathologies, with certain dimensions being more prevalent in particular disorders.
The process of high energy electron acceleration along the surface of grating targets (GTs) that were irradiated by a relativistic, high-contrast laser pulse at an intensity
was studied. Our experimental results demonstrate that for a GT with a periodicity twice the laser wavelength, the surface electron flux is more intense for a laser incidence angle that is larger compared to the resonance angle predicted by the linear model. An electron beam with a peak charge of
, for electrons with energies
, was measured. Numerical simulations carried out with parameters similar to the experimental conditions also show an enhanced electron flux at higher incidence angles depending on the preplasma scale length. A theoretical model that includes ponderomotive effects with more realistic initial preplasma conditions suggests that the laser-driven intensity and preformed plasma scale length are important for the acceleration process. The predictions closely match the experimental and computational results.
Small intestinal epithelium homeostasis involves four principal cell types: enterocytes, goblet, enteroendocrine and Paneth cells. Epidermal growth factor (EGF) has been shown to affect enterocyte differentiation. This study determined the effect of dietary EGF on goblet, enteroendocrine and Paneth cell differentiation in piglet small intestine and potential mechanisms. Forty-two weaned piglets were used in a 2 × 3 factorial design; the major factors were time post-weaning (days 7 and 14) and dietary treatment (0, 200 or 400 µg/kg EGF supplementation). The numbers of goblet and enteroendocrine cells were generally greater with the increase in time post-weaning. Moreover, the supplementation of 200 µg/kg EGF increased (P < 0.01) the number of goblet and enteroendocrine cells in villus and crypt of the piglet small intestine as compared with the control. Dietary supplementation with 200 µg/kg EGF enhanced (P < 0.05) abundances of differentiation-related genes atonal homologue 1, mucin 2 and intestinal trefoil factor 3 messenger RNA (mRNA) as compared with the control. Piglets fed 200 or 400 µg/kg EGF diet had increased (P < 0.05) abundances of growth factor-independent 1, SAM pointed domain containing ETS transcription factor and pancreatic and duodenal homeobox 1 mRNA, but decreased the abundance (P < 0.01) of E74 like ETS transcription factor 3 mRNA as compared with the control. Animals receiving 400 µg/kg EGF diets had enhanced (P < 0.05) abundances of neurogenin3 and SRY-box containing gene 9 mRNA as compared with the control. The mRNA abundance and protein expression of lysozyme, a marker of Paneth cell, were also increased (P < 0.05) in those animals. As compared with the control, dietary supplementation with 200 µg/kg EGF increased the abundance of EGF receptor mRNA and the ratio of non-phospho(p)-β-catenin/β-catenin (P < 0.05) in villus epithelial cells at days 7 and 14. This ratio in crypt epithelial cells was higher (P < 0.05) on the both 200 and 400 µg/kg EGF groups during the same period. Our results demonstrated that dietary EGF stimulated goblet, enteroendocrine and Paneth cell differentiation in piglets during the post-weaning period, partly through EGFR and Wnt/β-catenin signalling.
Some studies have shown that the excessive metabolic heat production is the primary cause for dead chicken embryos during late embryonic development. Increasing heat shock protein (HSP) expression and adjusting metabolism are important ways to maintain body homeostasis under heat stress. This study was conducted to investigate the effects of in ovo injection (IOI) of vitamin C (VC) at embryonic age 11th day (E11) on HSP and metabolic genes expression. A total of 320 breeder eggs were randomly divided into normal saline and VC injection groups. We detected plasma VC content and rectal temperature at chick’s age 1st day, and the mRNA levels of HSP and metabolic genes in embryonic livers at E14, 16 and 18, analysed the promoter methylation levels of differentially expressed genes and predicted transcription factors at the promoter regions. The results showed that IOI of VC significantly increased plasma VC content and decreased rectal temperature (P < 0.05). In ovo injection of VC significantly increased heat shock protein 60 (HSP60) and pyruvate dehydrogenase kinase 4 (PDK4) genes expression at E16 and PDK4 and secreted frizzled related protein 1 (SFRP1) at E18 (P < 0.05). At E16, IOI of VC significantly decreased the methylation levels of total CpG sites and −336 CpG site in HSP60 promoter and −1137 CpG site in PDK4 promoter (P < 0.05). Potential binding sites for nuclear factor-1 were found around −389 and −336 CpG sites in HSP60 promoter and potential binding site for specificity protein 1 was found around −1137 CpG site in PDK4 promoter. Our results suggested that IOI of VC increased HSP60, PDK4 and SFRP1 genes expression at E16 and 18, which may be associated with the demethylation in gene promoters. Whether IOI of VC could improve hatchability needs to be further verified by setting uninjection group.
Thermal imaging diagnostics was used as a surface temperature mapping tool to characterize the energy density distribution of a high-intensity pulsed ion beam. This approach was tested on the TEMP-6 accelerator (200–250 kV, 150 ns). The beam composition included carbon ions (85%) and protons, and the energy density in the focus was 5–12 J/cm2. Targets of stainless steel, titanium, brass, copper, and tungsten were examined. Our observations show that the maximum energy density measured with the thermal imaging diagnostics considerably exceeds the ablation threshold of the targets. An analysis of the overheating mechanisms of each target was carried out, including metastable overheating of the target to above its boiling temperature during rapid heating; formation, migration, and the subsequent annealing of fast radiation-induced defects in the target under ion beam irradiation. This expands the range of energy density measurement for this thermal imaging diagnostics from 2–3 J/cm2 up to 10–12 J/cm2 but introduces error into the results of measurement. For a stainless steel target, this error exceeds 15% at an energy density of more than 4 J/cm2. A method of correcting the results of the thermal imaging diagnostics is developed for a pulsed ion beam under conditions of intense ablation of the target material.
An algorithm for Global Navigation Satellite System satellite atomic clock integrity monitoring based on an extended measurement model is proposed. A detection statistic achieved by parity transformation is used to detect clock anomalies, and the concept of the optimal accumulation number, with a method to find it, is provided. Numerical simulations are adopted to verify the validity of detecting two typical anomalies.
Force-feeding was considered as a traditional high-efficiency approach to improve growth performance and accelerate fat deposition of Pekin ducks. However, force-feeding is a serious violation of international advocacy on animal welfare, because it can induce serious injuries to animals, such as damages to the digestive tract, effects on immunity and even severe oxidative stress. Therefore, it is urgent to stop force-feeding. The aim of this study was to determine the effects of force feeding on immune function, digestive function and oxidative stress in the mucosa of duodenum and jejunum of Pekin ducks. A total of 500 ducks were randomly divided into two groups. The control group was allowed to feed freely on a basal diet. The experimental group was force-fed by inserting a plastic feeding tube 8 to 10 inches long down the esophagus for 6 days. Compared with the control group, there was a significant (P<0.05) increase in serum diamine oxidase, d-lactic acid, endotoxin and corticosterone levels in the force-feeding group. The crypt depth in duodenum and jejunum showed significant differences (P<0.05) between the two groups and the intestinal villus epithelium cell was severely damaged in force-feeding group. Similarly, the activities of digestive enzymes as well as the levels of immune function in the duodenal and jejunal mucosa in the force-feeding group were significantly higher than the control group (P<0.05). However, there was a significant decrease in the superoxide dismutase, glutathione peroxidase and catalase levels with a marked increase in malondialdehyde level in duodenal and jejunal mucosa (P<0.05). In summary, at the end of the fattening period with force-feeding for 6 days, Pekin ducks experienced an adverse effect on the integrity of their duodenal and jejunal mucosa epithelium cell as well as their immune function and antioxidant capacity of Pekin ducks but also had improvement in digestive enzyme activities.
To solve the on-ground lateral direction control problem of the unswept flying-wing unmanned aerial vehicle (UAV) without rudder, steering system or breaking system, a control approach which uses differential propeller thrust to control the lateral direction is proposed. First, a mathematical model of the unswept flying-wing UAV on-ground moving is established. Second, based on the active disturbance rejection control (ADRC) theory, a yaw angle controller is designed by using the differential propeller thrust as the control output. Finally, a straight line trajectory tracking control law is designed by improving the vector field path following method. Experiment results show that the proposed control laws have a shorter response time, better robustness and better control precision compared with proportional integral derivative (PID) controller. The proposed controller has small computational complexity, simple parameter setting process, and uses practical measurable physical quantities, providing a reference solution for further engineering applications.
Hypoimmunity and numerous stresses are two major challenges in broiler industry. Nutrient intervention at the specific time of embryonic stage is a feasible way to improve animal performance. This study was conducted to investigate the possible effects of in ovo feeding (IOF) of vitamin C at embryonic age 15th day (E15) on growth performance, antioxidation and immune function of broilers. A total of 240 broiler fertile eggs were randomly divided into two groups (0 and 3 mg injected dose of vitamin C at E15), and new-hatched chicks from each treatment were randomly allocated into six replicates with 10 chicks per replicate after incubation. The results indicated that in ovo vitamin C injection improved the hatchability (P < 0.05) and increased immunoglobulin M (IgM) (at the broiler’s age 1st day, D1), IgG and IgM concentrations (D21), as well as lysozyme activity (D21, P < 0.05) and total antioxidant capacity (D42, P < 0.01) in plasma of broilers. On D21, the splenic expression level of DNA methyltransferase 1 (DNMT1) was up-regulated in vitamin C (VC) group, whereas interleukin (IL)-6, interferon-γ, ten-eleven translocation protein 1 and thymine-DNA glycosylase were down-regulated (P < 0.05). On D42, in ovo vitamin C injection up-regulated splenic expression levels of DNMT1, DNA methyltransferase 3B (DNMT3B) and growth arrest and DNA-damage-inducible protein beta (P < 0.05), whereas down-regulated splenic expression levels of IL-6, tumour necrosis factor-α and methyl-CpG-binding domain protein 4 (P < 0.05). Our findings suggested that IOF of 3 mg vitamin C at E15 could improve, to some extent, the antioxidant activity and immune function in plasma, corresponding with the lower expression of pro-inflammatory cytokines in spleen. However, IOF of vitamin C leading to the changes in the expression of DNA methyltransferases and demethylases may suggest an increased trend of DNA methylation level in spleen and whether DNA methylation variation is associated with the lower expression of pro-inflammatory cytokines in spleen warrants future study.
A new generation of high power laser facilities will provide laser pulses with extremely high powers of 10 petawatt (PW) and even 100 PW, capable of reaching intensities of
in the laser focus. These ultra-high intensities are nevertheless lower than the Schwinger intensity
at which the theory of quantum electrodynamics (QED) predicts that a large part of the energy of the laser photons will be transformed to hard Gamma-ray photons and even to matter, via electron–positron pair production. To enable the investigation of this physics at the intensities achievable with the next generation of high power laser facilities, an approach involving the interaction of two colliding PW laser pulses is being adopted. Theoretical simulations predict strong QED effects with colliding laser pulses of
focused to intensities