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The sense of bitter taste is critical for chickens to acquire and select feeds. It is important to understand the roles and mechanisms of bitter taste transduction in chickens. Denatonium is extensively used as a bitter taste receptor agonist to activate bitter taste receptors in recent studies. The objective of this study was to investigate the physiological effects and the potential molecular mechanisms of dietary exposure to a strong bitter taste receptor agonist on the jejunal epithelial cells of yellow-feathered chickens. A total of 240 yellow-feathered chickens were divided into four treatments receiving a normal diet (Control), a low-dose denatonium treatment (Control + 5 mg/kg denatonium), a middle-dose denatonium treatment (Control + 20 mg/kg denatonium) and a high-dose denatonium treatment (Control + 100 mg/kg denatonium) for 56 days, respectively. The results showed that dietary denatonium reduced (P < 0.05) the growth performance of chickens. High-dose denatonium damaged the morphology of the jejunal epithelium and decreased (P < 0.05) the activities of Ca2+-ATPase, sucrase and maltase after 56 days of exposure. Meanwhile, high-dose denatonium increased (P < 0.05) mRNA expressions of bitter taste receptors, which resulted in enhanced apoptosis in jejunal epithelial cells after 56 days of exposure. Furthermore, middle-dose and high-dose denatonium exhibited increased (P < 0.05) mRNA level of claudin 2 and decreased (P < 0.05) mRNA level of occludin after 28 days of exposure. Only high-dose denatonium decreased (P < 0.05) mRNA level of occludin after 56 days of exposure. In conclusion, denatonium manifested deleterious effects on the jejunum of chickens in a dose–effect manner via damaging the morphology of the jejunal epithelium, and inducing apoptosis associated with bitter taste receptors. Our data suggest that bitter-tasting feed additives may have side effects on the growth and development of intestines in chickens.
Rumen-protected betaine (RPB) can enhance betaine absorption in the small intestine of ruminants, while betaine can alter fat distribution and has the potential to affect the meat quality of livestock. Hence, we hypothesized that RPB might also affect the meat quality of lambs. Sixty male Hu sheep of similar weight (30.47 ± 2.04 kg) were selected and randomly subjected to five different treatments. The sheep were fed a control diet (control treatment, CTL); 1.1 g/day unprotected-betaine supplemented diet (UPB); or doses of 1.1 g/day (low RPB treatment; L-PB), 2.2 g/day (middle RPB treatment; M-PB) or 3.3 g/day (high RPB treatment; H-PB) RPB-supplemented diet for 70 days. Slaughter performance, meat quality, fatty acid and amino acid content in the longissimus dorsi (LD) muscle, shoulder muscle (SM) and gluteus muscle (GM) were measured. Compared with CTL, betaine (including UPB and RPB) supplementation increased the average daily weight gain (ADG) (P < 0.05) and average daily feed intake (P < 0.01) of lambs. Rumen-protected betaine increased ADG (P < 0.05) compared with UPB. With increasing RPB doses, the eye muscle area of the lambs linearly increased (P < 0.05). Compared with CTL, betaine supplementation decreased water loss (P < 0.05) in SM and increased pH24 in the SM (P < 0.05) and GM (P < 0.05). Compared with UPB, RPB decreased water loss in the GM (P < 0.01), decreased shear force (P < 0.05) in the LD and SM and increased the pH of the meat 24 h after slaughter (pH24). With increasing RPB doses, the shear force and b* value in the LD linearly decreased (P < 0.05), and the pH24 of the meat quadratically increased (P < 0.05). Compared with CTL, betaine supplementation increased the polyunsaturated fatty acid in the GM (P < 0.05). Compared with UPB, RPB supplementation decreased the saturated fatty acid (SFA) content in the LD (P < 0.05) and increased the unsaturated fatty acids (UFA), mono-unsaturated fatty acids and UFA/SFA ratio in the LD (P < 0.05). Compared with CTL, the content of histidine in the LD increased with betaine supplementation. Compared with UPB, RPB supplementation increased the content of total free amino acids and flavor amino acids in the LD of lambs (P < 0.05). With increasing RPB, the isoleucine and phenylalanine contents in the LD linearly increased (P < 0.05). Overall, the data collected indicated that the meat quality of lambs (especially in the LD) improved as a result of betaine supplementation, and RPB showed better effects than those of UPB.
The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
Sodium and chloride are the key factors maintaining normal osmotic pressure (OSM) and volume of the extracellular fluid, and influencing the acid–base balance of body fluids. The experiment was conducted to investigate the effects of dietary Na+ and Cl− level on growth performance, excreta moisture, blood biochemical parameters, intestinal Na+–glucose transporter 1 (SGLT1) messenger RNA (mRNA), and Na+–H+ exchanger 2 (NHE2) mRNA, and to estimate the optimal dietary sodium and chlorine level for yellow-feathered chickens from 22 to 42days. A total of 900 22-day-old Lingnan yellow-feathered male chickens were randomly allotted to five treatments, each of which included six replicates of 30 chickens per floor pen. The basal control diet was based on corn and soybean meal (without added NaCl and NaHCO3). Treatments 2 to 5 consisted of the basal diet supplemented with equal weights of Na+ and Cl−, constituting 0.1%, 0.2%, 0.3% and 0.4% of the diets. Supplemental dietary Na+ and Cl− improved the growth performance (P<0.05). Average daily gain (ADG) showed a quadratic broken-line regression to increasing dietary Na+ and Cl− (R2=0.979, P<0.001), and reached a plateau at 0.1%. Supplemental Na+ and Cl− increased (P<0.05) serum Na+ and OSM in serum and showed a quadratic broken-line regression (R2=0.997, P=0.004) at 0.11%. However, supplemental Na+ and Cl− decreased (P<0.05) serum levels of K+, glucose (GLU) and triglyceride. Higher levels of Na+and Cl− decreased duodenal NHE2 transcripts (P<0.05), but had no effect on ileal SGLT1 transcripts. The activity of Na+ /K+-ATPase in the duodenum decreased (P<0.05) with higher levels of dietary Na+ and Cl−. In conclusion, the optimal dietary Na+ and Cl− requirements for yellow-feathered chickens in the grower phase, from 22 to 42 days of age, to optimize ADG, serum Na+, OSM, K+ and GLU were 0.10%, 0.11%, 0.11%,0.17% and 0.16%, respectively, by regression analysis.
It is a challenge for small, fixed-wing aerial vehicles to maintain flight stability under gusts. Inspired by the geometric features and the structural dynamic characteristics of the gliding bird wing, an elastic wing with similar characteristics was designed and optimised for use as part of unmanned aerial vehicle. A flight dynamic model, which includes the coupling of the longitudinal flight modes and the aeroelastic modes of the flexible wing, was built to analyse the mechanisms of specific coupling for the structural characteristics of the wing design, and how these specific couplings affect flight dynamics. The results showed that the bio-inspired elastic wing effectively allows alleviation of the gust response of the prototype through coupling effects of the short period and the first aeroelastic mode, even with a considerable frequency gap. These effects become more significant when the airspeed becomes larger. The conclusions of this research can facilitate further development of bird-sized unmanned aerial vehicles to extend their applications and make these vehicles more adaptive for flight in complex atmospheric environments.
It was reported that high blood cholesterol levels increased the susceptibility to mitochondrial dysfunction. This study hypothesized that the gestational hypercholesterolemia (HC) could induce the mitochondrial dysfunction in term human placenta. The eligible pregnant women were recruited from Xuanwu Hospital in Beijing during their first prenatal visit (before their 10th week of pregnancy). In total, 19 pregnant women whose serum total cholesterol levels were higher than 7.25 mm at third trimester (measured at 36–38 weeks) were selected as gestational HC. Other 19 pregnant women with normal cholesterol level matched with age, pre-gestational body mass index, and the neonatal gender were included as the control group. Full-term placenta samples were collected. The mitochondrial DNA (mtDNA) copy number, messenger RNA (mRNA) expression of cytochrome c oxidase subunit I, adenosine triphosphate monophosphatase 6 (ATP6ase), citrate synthase, peroxisome proliferator-activated receptor-γ (PPARγ) co-activator 1α, PPARγ co-activator 1β and estrogen-related receptor-α, and the activity of mitochondrial respiratory chain enzyme complex were measured. Pregnancy outcomes were obtained by extraction from medical records and the labor ward register. The results showed that only placental mtDNA copy number and mRNA expression of ATP6ase were significantly decreased in HC group. No significant differences were detected of other measurements between the two groups. These findings indicated that gestational HC might not induce the damage of placental function seriously.
The bird cherry-oat aphid Rhopalosiphum padi (L.) is one of the most important wheat pests with polyphagia and autumn migrants. And, chemosensory genes were thought to play a key role in insect searching their hosts, food and mate. However, a systematic identification of the chemosensory genes in this pest has not been reported. Thus, in this study, we identified 14 odorant-binding proteins, nine chemosensory proteins, one sensory neuron membrane protein, 15 odorant receptors, 19 gustatory receptors and 16 ionotropic receptors from R. padi transcriptomes with a significantly similarity (E-value < 10−5) to known chemosensory genes in Acyrthosiphon pisum and Aphis gossypii. In addition, real-time quantitative polymerase chain reaction (RT-qPCR) was employed to determine the expression profiles of obtained genes. Among these obtained genes, we selected 23 chemosensory genes to analyze their expression patterns in different tissues, wing morphs and host plants. We found that except RpOBP1, RpOBP3, RpOBP4 and RpOBP5, the rest of the selected genes were highly expressed in the head with antennae compared with body without head and antennae. Besides that, the stimulation and depression of chemosensory genes by plant switch indicated that chemosensory genes might be involved in the plant suitability assessment. These results not only provide insights for the potential roles of chemosensory genes in plant search and perception of R. padi but also provide initial background information for the further research on the molecular mechanism of the polyphagia and autumn migrants of it. Furthermore, these chemosensory genes are also the candidate targets for pest management control in future.
About 30,000 astronomical photographic plates were digitised between 2012–2017 with a special digitising machine that has high precision in both astrometry and photometry. All the images from the plates, together with plate information and measured coordinates of all the objects on the plates, have been stored in the Chinese Virtual Observatory.
A liquid chromatography mass spectrometry method for determination of clothianidin in brown rice, straw, rice hull, paddy water and paddy sediment was developed and residue levels were determined in the different components. The limit of quantification was set at 0·01 mg/kg for the matrices studied. Clothianidin degradation in straw, paddy water and soil was studied, and clothianidin residues in brown rice, straw, hull and paddy soil were determined. Concurrent recoveries were between 85·6 and 92·5%, with relative standard deviations ranging from 1·3 to 6·8% at three fortification levels between 0·01 and 5·0 mg/kg. The half-lives in straw, paddy water and paddy sediment were found to be 1·9–4·9, 4·1–5·0 and 4·9–6·3 days, respectively. The maximum residues in brown rice, straw, hull and paddy soil samples were 0·38, 1·88, 1·38 and 0·14 mg/kg, respectively.
Diarrhea is a common cause of morbidity and mortality and the incidence of diarrhea in the world has changed little over the past four decades. To assess the prevalence of and healthcare practices for diarrhea, a cross-sectional study was conducted in Pudong, Shanghai, China. In October 2014, a total of 5324 community residents were interviewed. Respondents were asked if they had experienced diarrhea (defined as ⩾3 passages of watery, loose, bloody, or mucoid stools within a 24-h period) in the previous month prior to the interview. The monthly prevalence of diarrhea was 4·1% (95% CI: 3·3–4·8), corresponding to an incidence rate of 0·54 episodes per person-year. The proportion of individuals with diarrhea who sought healthcare was 21·2% (95% CI: 13·4–29·0). Diarrhea continues to impose a considerable burden on the community and healthcare system in Pudong. Young age and travel were identified as predictors of increased diarrhea occurrence.
To investigate the effect of microRNA let-7a on OPN expression in a mouse model of allergic rhinitis.
Thirty-two mature female C57BL/6 mice were randomly divided into four groups, with eight mice in each group: microRNA let-7a, microRNA control, OVA and phosphate-buffered saline groups. The microRNA let-7a, microRNA control and OVA groups were sensitised with OVA to establish a mouse model of allergic rhinitis. Nose-scratching events were counted. Nasal mucosa was used to evaluate histological changes of goblet cell hyperplasia. Interleukins 5 and 13 were detected. Interferon-γ levels in the nasal lavage fluid were assayed with enzyme-linked immunosorbent assay. OPN expression was estimated with polymerase chain reaction.
Compared with microRNA control mice, microRNA let-7a treated mice had a significantly increased number of nose-scratching events, nasal mucosal eosinophilia and goblet cell hyperplasia (p < 0.05), and significantly higher interleukins 5 and 13 in nasal mucosa (p < 0.05), but there was no significant difference in interferon-γ (p > 0.05). In addition, microRNA let-7a treated mice had significantly enhanced OPN expression in nasal mucosa (p < 0.05).
MicroRNA let-7a can promote allergic rhinitis development partly by regulating OPN expression.
Mesoscale heterogeneous material systems are efficient and adaptive to real world environments, owing to the non-uniform stress fields that result from the convolution of component geometries, loading conditions, and environmental changes. With the advent of multi-material additive manufacturing, the production of heterogeneous material systems with a pre-defined mesoscale material distribution becomes feasible. This unlocks the design freedom at a characteristic length scale between the macroscale geometry and microstructures, but also calls for a new design framework to optimize the mesoscale material distribution in multi-material additive manufacturing. Here, we propose and demonstrate such a design framework by incorporating digital image correlation-based deformation mapping with 3D finite element modeling-based computational optimization. The constitutive behavior of each constituent material or their mixtures is calibrated by matching the local deformation data. The optimal mesoscale material distribution can then be determined using global optimization algorithms and validated experimentally.
The paper is devoted to the shapes of the solar wind ion flux fluctuation spectrum at the transition between the inertial and the kinetic range using in situ high-resolution measurements of the Russian mission Spektr-R. We analyse the variability of the transition region and select five typical types of spectral shapes: (i) spectra with two slopes and one break, (ii) spectra characterized by a nonlinear steepening in the kinetic range, (iii) spectra with flattening in the vicinity of the break, (iv) spectra with a bump in the vicinity of the break and (v) spectra without any steepening in the kinetic range. The most popular is the well-known type (i) observed in approximately half of the cases. The second most popular type of spectra is type (iii) occurring in approximately one third of the cases. The other three types are observed less often: type (ii) – in approximately 6 %; type (iv) in 3 % and type (v) in 6 % of cases. An analysis of typical plasma conditions for different types of spectra revealed that the last two type of spectra (iv) and (v) are generally observed in a very slow solar wind with a low proton density, (i) and (iii) are observed in the solar wind with rather typical conditions and (ii) is usually observed in high-speed streams. The effect of nonlinear steepening of the spectra in the kinetic range increases with the solar wind speed. We present also the analysis of statistical properties of the observed events and compare them with the predictions of several statistical turbulence models. We show that intermittency is always observed in the solar wind flow despite the presence of one or another shape of spectra. The log-Poisson model with a dominant contribution of filament-like structures shows the best parameterization of the experimentally observed scaling.
MicroRNAs (miRNAs) are a class of small non-coding RNAs that negatively regulate gene expression of target messenger RNAs (mRNAs) and miRNAs have been proven to play vital roles in skeletal muscle development. The miRNA-499-5p has been reported to be negatively related with the expression of Sox6, a critical transcription factor for the maintenance of fast-twitch skeletal muscle. In this study, we amplified a length of 2012-bp mRNA that contains a 1512-bp porcine Sox6 (pSox6) 3'UTR from skeletal muscle of a Duroc×Landrace×Yorkshire pig. By luciferase reporter assay we verified that pSox6 is a target of miR-499-5p. In extensor digitorum longus and Soleus muscles of pigs, the expression levels of miR-499-5p and pSox6 mRNA were also inversely correlated. Besides, overexpression of miR-499-5p in porcine satellite cells promoted the expression of MyHC I and MyHC IIa mRNA, along with a reduction of pSox6 mRNA. Taken together, these results indicate that miR-499-5p may facilitate the oxidative myofibers formation by downregulating pSox6 expression.
Relativistic collisionless shock charged particle acceleration is considered as a possible origin of high-energy cosmic rays. However, it is hard to explore the nature of relativistic collisionless shock due to its low occurring frequency and remote detecting distance. Recently, there are some works attempt to solve this problem by generating relativistic collisionless shock in laboratory conditions. In laboratory, the scheme of generation of relativistic collisionless shock is that two electron–positron pair plasmas knock each other. However, in laboratory, the appropriate pair plasmas have been not generated. The 10 PW laser pulse maybe generates the pair plasmas that satisfy the formation condition of relativistic collisionless shock due to its ultrahigh intensity and energy. In this paper, we study the positron production by ultraintense laser high Z target interaction using numerical simulations, which consider quantum electrodynamics effect. The simulation results show that the forward positron beam up to 1013/kJ can be generated by 10 PW laser pulse interacting with lead target. The estimation of relativistic collisionless shock formation shows that the positron yield satisfies formation condition and the positron divergence needs to be controlled. Our results indicate that the generation of relativistic collisionless shock by 10 PW laser facilities in laboratory is possible.
An analytical solution is launched for Twin-cell Composite Box Beam (TCCBB) considering the impact of shear lag effects of concrete slab and twin-cell steel girder. To in-depth explore its mechanical mechanism, a new warping displacement mode of wide flange is chosen to meet the essential deformation feature of this TCCBB model by authors. Combining the virtual work principle with the thin-walled beam theory, its governing equations and boundary conditions are established for the TCCBB model. Closed form solutions for longitudinal strain and its shear lag coefficients are also derived under concentrated loads. What's more, experiment investigation and related parameter impact analysis are carried out for this established TCCBB model. Through this research, it shows that the proposed method can be applied to describe and predict shear lag behaviors for this type of composite structure. That further suggests that it provides a certain reference value for engineering design and its late reinforcement and maintenance in the composite structure.
This study aimed to test the expression of maspin in invasive fungal rhinosinusitis and explore its value in diagnosing invasive fungal rhinosinusitis.
Forty-two fungal rhinosinusitis cases (12 invasive and 30 non-invasive) were selected as the experimental group, and 30 chronic rhinosinusitis cases comprised the control group. Maspin expression was assessed in nasal mucous membrane specimens by immunohistochemical staining.
Compared with the control group, maspin expression was down-regulated in the fungal rhinosinusitis group (p < 0.05). Furthermore, the staining score for maspin was lowest in the invasive fungal rhinosinusitis group, as compared with both the non-invasive fungal rhinosinusitis group and the control group (p < 0.05). A maspin staining score of 5.70 was the critical value for diagnosis of invasive fungal rhinosinusitis, with sensitivity and specificity of 91.7 per cent and 88.3 per cent, respectively.
The results of this study suggest that the maspin staining score may be a biomarker for effective and rapid diagnosis of invasive fungal rhinosinusitis.
Worldwide 350 million people suffer from major depression, with the majority of cases occurring in low- and middle-income countries. We examined the patterns, correlates and care-seeking behaviour of adults suffering from major depressive episode (MDE) in China.
A nationwide study recruited 512 891 adults aged 30–79 years from 10 provinces across China during 2004–2008. The 12-month prevalence of MDE was assessed by the Modified Composite International Diagnostic Interview-short form. Logistic regression yielded adjusted odds ratios (ORs) of MDE associated with socio-economic, lifestyle and health-related factors and major stressful life events.
Overall, 0.7% of participants had MDE and a further 2.4% had major depressive symptoms. Stressful life events were strongly associated with MDE [adjusted OR 14.7, 95% confidence interval (CI) 13.7–15.7], with a dose–response relationship with the number of such events experienced. Family conflict had the highest OR for MDE (18.9, 95% CI 16.8–21.2) among the 10 stressful life events. The risk of MDE was also positively associated with rural residency (OR 1.5, 95% CI 1.4–1.7), low income (OR 2.3, 95% CI 2.1–2.4), living alone (OR 2.6, 95% CI 2.3–3.0), smoking (OR 1.4, 95% CI 1.3–1.6) and certain other mental disorders (e.g. anxiety, phobia). Similar, albeit weaker, associations were observed with depressive symptoms. Among those with MDE, about 15% sought medical help or took psychiatric medication, 15% reported having suicidal ideation and 6% reported attempting suicide.
Among Chinese adults, the patterns and correlates of MDE were generally consistent with those observed in the West. The low rates of seeking professional help and treatment highlight the great gap in mental health services in China.