To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
A stable reference gene is a key prerequisite for accurate assessment of gene expression. At present, the real-time reverse transcriptase quantitative polymerase chain reaction has been widely used in the analysis of gene expression in a variety of organisms. Neoseiulus barkeri Hughes (Acari: Phytoseiidae) is a major predator of mites on many important economically crops. Until now, however, there are no reports evaluating the stability of reference genes in this species. In view of this, we used GeNorm, NormFinder, BestKeeper, and RefFinder software tools to evaluate the expression stability of 11 candidate reference genes in developmental stages and under various abiotic stresses. According to our results, β-ACT and Hsp40 were the top two stable reference genes in developmental stages. The Hsp60 and Hsp90 were the most stable reference genes in various acaricides stress. For alterations in temperature, Hsp40 and α-TUB were the most suitable reference genes. About UV stress, EF1α and α-TUB were the best choice, and for the different prey stress, β-ACT and α-TUB were best suited. In normal conditions, the β-ACT and α-TUB were the two of the highest stable reference genes to respond to all kinds of stresses. The current study provided a valuable foundation for the further analysis of gene expression in N. barkeri.
Phenoloxidase (PO) plays a key role in melanin biosynthesis during insect development. Here, we isolated the 2310-bp full-length cDNA of PPO1 from Zeugodacus tau, a destructive horticultural pest. qRT-polymerase chain reaction showed that the ZtPPO1 transcripts were highly expressed during larval–prepupal transition and in the haemolymph. When the larvae were fed a 1.66% kojic acid (KA)-containing diet, the levels of the ZtPPO1 transcripts significantly increased by 2.79- and 3.39-fold in the whole larvae and cuticles, respectively, while the corresponding PO activity was significantly reduced; in addition, the larval and pupal durations were significantly prolonged; pupal weights were lowered; and abnormal phenotypes were observed. An in vitro inhibition experiment indicated that KA was an effective competitive inhibitor of PO in Z. tau. Additionally, the functional analysis showed that 20E could significantly up-regulate the expression of ZtPPO1, induce lower pupal weight, and advance pupation. Knockdown of the ZtPPO1 gene by RNAi significantly decreased mRNA levels after 24 h and led to low pupation rates and incomplete pupae with abnormal phenotypes during the larval-pupal interim period. These results proved that PO is important for the normal growth of Z. tau and that KA can disrupt the development of this pest insect.
Nitrogen (N) application and irrigation to winter wheat may decrease leaf temperature and enhance photosynthesis: as a result, more photosynthates will be allocated to the grains, resulting in higher grain yields. To investigate this hypothesis, a 2-year field study was conducted with three levels of N fertilizer application (no fertilizer, N0; 240 kg N/ha, N1; 360 kg N/ha, N2) and two different water regimes (rainfed with no irrigation, R; irrigation at the over-wintering, stem elongation and grain filling stages, W). The results show that both N application and supplemental irrigation significantly increased grain yield with increases in both grain number/m2 and the 1000-grain weight, viz., WN2>WN1>WN0>RN2>RN1>RN0. In addition, application of N under both water regimes significantly increased flag leaf area, above-ground biomass and single stem productivity and decreased leaf temperature, which led to an increase in net photosynthesis rates and ribulose bisphosphate (RuBP) carboxylase activity. Moreover, analysis of the chlorophyll α fluorescence transient showed that N fertilizer application and supplemental irrigation significantly increased electron donor and acceptor performance of the photosystem II reaction centre.
Human cystic echinococcosis is a widespread, chronic, endemic, helminthic zoonosis caused by larval tapeworms of the species Echinococcus granulosus. At present, there is no rational and effective therapy for patients with echinococcosis. The present study evaluated whether the combination of alkaloids from Sophora moorcroftiana seeds (SMSa2) and Bacillus Calmette–Guérin (BCG) was effective in the treatment of experimental echinococcosis. After 20 weeks of secondary infection with protoscoleces, mice were randomly allocated to five groups and treated for 6 weeks by daily intragastric administration of albendazole (ABZ, 100 mg/kg), SMSa2 (100 mg/kg), BCG (abdominal subcutaneous injection at 5 × 106 CFU), SMSa2 + BCG (100 mg/kg SMSa2 and 5 × 106 CFU BCG) or normal saline (untreated group), respectively. The results indicated a significant reduction in the weight of hydatid cysts in the SMSa2 + BCG group compared with the untreated, SMSa2 and BCG groups. The rate of inhibition of hydatid cyst growth in the SMSa2 + BCG group (76.1%) was obviously increased compared with that in the SMSa2 (25.7%) and BCG (26.6%) groups, respectively. Compared with the untreated control, the SMSa2 + BCG group showed a non-significant increase in serum interleukin-4 (IL-4). Furthermore, the serum levels of interferon-γ (IFN-γ) between the untreated and SMSa2 + BCG groups were not statistically different. Therefore, the combination of alkaloids from S. moorcroftiana seeds and BCG can reduce cyst burden and is an effective therapeutic regimen against echinococcosis.
This study aimed to evaluate the acaricidal activity of lettuce (Lactuca sativa) extracts against carmine spider mites (Tetranychus cinnabarinus Boisd.) and isolate the acaricidal components. Acaricidal activities of lettuce extracts isolated from different parts (the leaf, root and seed) using various solvents (petroleum ether, acetone and methanol) were evaluated with slide-dip bioassay and relatively high median lethal concentration (LC50) values were detected. Acetone extracts of lettuce leaves harvested in July and September were fractionated and isolated with silica gel and thin-layer chromatography. Consequently, acetone extracts of lettuce leaves harvested in July exhibited higher acaricidal activity than those harvested in September, with an LC50 value of 0.268 mg ml−1 at 72 h post-treatment. A total of 27 fractions were obtained from the acetone extract of lettuce leaves harvested in July, and mite mortalities with the 11th and 12th fractions were higher than those with the other 25 fractions (LC50: 0.751 and 1.258 mg ml−1 at 48 h post-treatment, respectively). Subsequently, active acaricidal components of the 11th fraction were identified by infrared, nuclear magnetic resonance and liquid chromatography/mass spectrometry. Five components were isolated from the 11th fraction, with components 11-a and 11-b showing relatively high acaricidal activities (LC50: 0.288 and 0.114 mg ml−1 at 48 h post-treatment, respectively). Component 11-a was identified as β-sitosterol. In conclusion, acetone extracts of lettuce leaves harvested in July might be used as a novel phytogenic acaricide to control mites.
Neoseiulus barkeri (HUGHES) is the natural enemy of spider mites, whiteflies and thrips. Screening for chemically-resistant predatory mites is a practical way to balance the contradiction between the pesticide using and biological control. In this study, the number of eggs laid by fenpropathrin-susceptible and resistant strains of N. barkeri was compared. Additionally, we cloned three N. barkeri vitellogenin (Vg) genes and used quantitative real-time polymerase chain reaction to quantify Vg expression in susceptible and resistant strains. The total number of eggs significantly increased in the fenpropathrin-resistant strain. The full-length cDNA cloning of three N. barkeri Vg genes (NbVg1, NbVg2 and NbVg3) revealed that the open reading frames of NbVg1, NbVg2 and NbVg3 were 5571, 5532 and 4728 bp, encoding 1856, 1843 and 1575 amino acids, respectively. The three N. barkeri Vg possessed the Vitellogenin-N domain (or lipoprotein N-terminal domain (LPD_N)), von Willebrand factor type D domain (VWD) and the domain with unknown function 1943 (DUF1943). The NbVg1 and NbVg2 expression levels were significantly higher in the resistant strain than in the susceptible strain, while the NbVg3 expression level was lower in the resistant strain. Thus, we speculate that the increased number of eggs laid by the fenpropathrin-resistant strain of N. barkeri may be a consequence of changes in Vg gene expression.
The role of the protozoan parasite Toxoplasma gondii in the pathogenesis of liver disease has recently gained much interest. The aim of this study was to determine the prevalence and risk factors associated with T. gondii infection in patients with liver disease from three cities in Shandong and Henan provinces, China. A case–control study was conducted from December 2014 to November 2015 and included 1142 patients with liver disease and 1142 healthy controls. Serum samples were collected from all individuals and were examined with enzyme-linked immunosorbent assay for the presence of anti-T. gondii IgG and IgM antibodies. Information on the demographics, clinical, and lifestyle characteristics of the participants was collected from the medical records and by the use of a questionnaire. The prevalence of anti-T. gondii IgG was 19·7% in patients with liver disease compared with 12·17% in the controls. Only 13 patients had anti-T. gondii IgM antibodies compared with 12 control individuals (1·14% vs. 1·05%, respectively). The highest seroprevalence was detected in patients with liver cancer (22·13%), followed by hepatitis patients (20·86%), liver cirrhosis patients (20·42%), and steatosis patients (20%). Multivariate logistic regression analysis indicated that consumption of raw meat (odds ratio (OR) = 1·32; 95% confidence interval (CI) 1·01–1·71; P = 0·03) and source of drinking water from wells (OR = 1·56; 95% CI 1·08–2·27; P = 0·01) were independent risk factors for T. gondii infection in liver disease patients. These findings indicate that T. gondii infection is more likely to be present in patients with liver disease. Therefore, efforts should be directed toward health education of populations at high risk of T. gondii infection and measures should be taken to protect vulnerable patients with liver disease.
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.
Twenty Small Tailed Han (STH) and 20 Ujumqin (UJU) ewes naturally infected with gastrointestinal nematodes were randomly assigned to one of four treatments arranged in a 2 × 2 factorial design, receiving anthelmintic treatment (AT) or non-anthelmintic treatment (NonAT) prior to lambing. After lambing, the effects of AT on feed intake, digestion and milk yield in ewes, and the growth rates of lambs fed their mother's milk were assessed for 28 days. Faecal samples were collected to determine faecal egg counts (FECs), milk was collected to measure milk yield and ewes and lambs were weighed to quantify daily body weight change. The results showed that AT significantly increased ewe dry matter intake (2411 g/d for AT and 2209 g/d for NonAT) and decreased FECs (50 eggs/g for AT and 2655 eggs/g for NonAT). All ewes lost weight after lambing, but body weight loss in the AT (43 g/d) was significantly less than in NonAT (84 g/d), and STH ewes (70 g/d) lost more weight than UJU ewes (58 g/d). Anthelmintic-treated ewes produced more milk for their lambs to consume. However, the extent of these positive effects of AT differed between STH and UJU ewes. The average daily body weight gain of lambs in AT was higher than those in NonAT. In conclusion, effective AT in ewes before lambing benefits subsequent lactation in ewes and growth rate in lambs.
We discuss a model for polarization of pulsar radio emission, based on the assumption that waves propagate in two elliptically polarized natural modes. Some results from numerical simulation of single pulses are discussed with emphasis on circular polarization, microstructures and single pulse statistics.
The absorption counterpart of curvature emission is reexamined based on the Landau-Lifshitz approach. Early derivations led to the conclusion that maser emission is not possible, but these early derivations neglected a drift effect which was first discussed by Zheleznyakov and Shaposhnikov. When the drift effect is included, the derivation implies that curvature maser emission is possible. It is shown that for maser emission to be possible, the Lorentz factor needs to satisfy γ ≳ 103 for radius of curvature of the magnetic field lines RB ≈ 106 to 109cm and frequency ω ≈ 107 to 1011 s−1. Possible application to pulsars is discussed.
A large-scale network named the default mode network (DMN) dynamically cooperates and competes with an external attention system (EAS) to facilitate various cognitive functioning that is prominently impaired in schizophrenia. However, it is unclear whether the cognitive deficit in schizophrenia is related to the disrupted competition and/or cooperation between these two networks.
A total of 35 schizophrenia patients and 30 healthy controls were scanned using gradient-echo echo-planar imaging during n-back working memory (WM) processing. Brain activities of the DMN and EAS were measured using general linear modelling of the functional magnetic resonance imaging data. Dynamic interaction between the DMN and EAS was decomposed into two directions using Granger causality analysis.
We observed a significant failure of DMN suppression in patients with schizophrenia, which was significantly related to WM/attentional deficit. Granger causality modelling showed that in healthy controls, while the EAS inhibitorily influenced the DMN, the DMN exerted an ‘excitatory’ or cooperative influence back on the EAS, especially in those with lower WM accuracy. In schizophrenia, this ‘excitatory’ DMN→EAS influence within the reciprocal EAS–DMN loop was significantly reduced, especially in patients with WM/attentional deficit.
The dynamic interaction between the DMN and EAS is likely to be comprised of both competitive and cooperative influences. In healthy controls, both the ‘inhibitory’ EAS→DMN interaction and ‘excitatory’ DMN→EAS interaction are correlated with WM performance. In schizophrenia, reduced ‘cooperative’ influence from the DMN to dorsal nodes of the EAS occurs in the context of non-suppression of the DMN and may form a possible pathophysiological substrate of WM deficit and attention disorder.
We derive zphot for sources in the entire (~0.4 deg2) H-HDF-N field with the EAzY code, based on PSF-matched broad-band (U band to IRAC 4.5 μm) photometry. Our catalog consists of a total of 131,678 sources. We find σNMAD = 0.029 for non-X-ray sources. We also classify each object as a star or galaxy through SED fitting. Furthermore, we match our catalog with the 2 Ms CDF-N main X-ray catalog. For the 462 matched non-stellar X-ray sources, we improve their zphot quality (σNMAD = 0.035) by adding three additional AGN templates. We make our photometry and zphot catalog publicly available.
Thermo-camera is employed here to analyze kinds of quality abnormal and improve production process during manufacture procedure of silicon-based thin-film solar modules. It shows that thermo-camera device can help engineers to solve problem of production line quickly and accurately, and save the manpower and financial resources at the same time.
The aim of this study was to investigate the variations in meat quality, lipid metabolism-related genes, myosin heavy chain (MyHC) isoform genes and peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) gene mRNA expressions in longissimus dorsi muscle (LM) of two different pig breeds. Six Rongchang and six Landrace barrows were slaughtered at 161 days of age. Subsequently, meat quality traits and gene expression levels in LM were observed. Results showed that Rongchang pigs not only exhibited greater pH, CIE a*24 h and intramuscular fat content but also exhibited lower body weight, carcass weight, dressing percentage, LM area and CIE b*24 h compared with Landrace pigs (P<0.05). Meanwhile, the mRNA expression levels of the lipogenesis (peroxisome proliferator-activated receptor gamma, acetyl-CoA carboxylase and fatty acid synthase) and fatty acid uptake (lipoprotein lipase)-related genes were greater in the Rongchang (P<0.05), whereas the lipolysis (adipose triglyceride lipase and hormone sensitive lipase) and fatty acid oxidation (carnitine palmitoyltransferase-1B)-related genes were better expressed in the Landrace. Moreover, compared with the Landrace, the mRNA expression levels of MyHCI, MyHCIIa and MyHCIIx were greater, whereas the mRNA expression levels of MyHCIIb were lower in the Rongchang pigs (P<0.05). In addition, the mRNA expression levels of PGC-1α were greater in Rongchang pigs than in the Landrace (P<0.05), which can partly explain the differences in MyHC isoform gene expressions between Rongchang and Landrace pigs. Although the small number of samples does not allow to obtain a definitive conclusion, we can suggest that Rongchang pigs possess better meat quality, and the underlying molecular mechanisms responsible for the better meat quality in fatty pigs may be partly due to the higher mRNA expression levels of lipogenesis and fatty acid uptake-related genes, as well as the oxidative and intermediate muscle fibers, and due to the lower mRNA expression levels of lipolysis and fatty acid oxidation-related genes, as well as the glycolytic muscle fibers.
MicroRNAs are endogenous ~22nt RNAs that negatively regulate gene expression at the posttranscriptional level via binding to the 3′-untranslated region (3′UTR) of target mRNAs. The microRNA miR-27a was reported to depress the expression of myostatin, a critical inhibitor of skeletal myogenesis, by binding to its 3′UTR in mouse. In this study, we cloned the full-length 3′UTR of porcine myostatin by rapid amplification of 3′-cDNA ends (3′-RACE) and demonstrated that the 3′UTR of porcine myostatin is targeted by miR-27a. The phenomenon that the level of myostatin inversely correlated with miR-27a was observed in fat and heart of pigs and also in proliferating porcine myoblasts. Besides, overexpression of miR-27a in porcine myoblasts promoted cell proliferation by reducing the expression of myostatin. Our data suggest that miR-27a positive regulates porcine myoblast proliferation via targeting myostatin.
Because cerebral morphological abnormalities in major depressive disorder (MDD) may be modulated by antidepressant treatment, inclusion of medicated patients may have biased previous meta-analyses of voxel-based morphometry (VBM) studies. A meta-analysis of VBM studies on medication-free MDD patients should be able to distinguish the morphological features of the disease itself from those of treatment.
A systematic search was conducted for the relevant studies. Effect-size signed differential mapping was applied to analyse the grey matter differences between all medication-free MDD patients and healthy controls. Meta-regression was used to explore the effects of demographics and clinical characteristics.
A total of 14 datasets comprising 400 medication-free MDD patients and 424 healthy controls met the inclusion criteria. The pooled meta-analysis and subgroup meta-analyses showed robustly reduced grey matter in prefrontal and limbic regions in MDD. Increased right thalamus volume was only seen in first-episode medication-naive patients, and increased grey matter in the bilateral anterior cingulate cortex only in medication wash-out patients. In meta-regression analyses the percentage of female patients in each study was negatively correlated with reduced grey matter in the right hippocampus.
By excluding interference from medication effects, the present study identified grey matter reduction in the prefrontal–limbic network in MDD. The subgroup meta-analysis results suggest that an increased right thalamus volume might be a trait directly related to MDD, while an increased anterior cingulate cortex volume might be an effect of medication. The meta-regression results perhaps reveal the structural underpinning of the sex differences in epidemiological and clinical aspects of MDD.
Low-dose clarithromycin has been recommended for the treatment of chronic rhinosinusitis without nasal polyps. However, it is uncertain whether a high dose of clarithromycin is more effective than a low dose.
Forty-three chronic rhinosinusitis patients were randomised to low-dose or high-dose clarithromycin groups, and clinical efficacy was evaluated. Pre- and post-treatment measures included: nasal symptom assessment, endoscopic inspection (Lund–Kennedy system), a quality of life questionnaire (the Sino-Nasal Outcome Test 20) and examination of cytokine levels (interleukin-5 and -8) in nasal secretions.
The high dose of clarithromycin was significantly better in terms of clinical efficacy than the low dose for the treatment of chronic rhinosinusitis (p < 0.025). Significant differences in nasal cytokine levels (interleukin-5 and -8) were also observed between the low-dose and high-dose groups after short-term clarithromycin treatment (p < 0.025).
Short-term, high-dose clarithromycin appears to be more effective for the treatment of chronic rhinosinusitis than low-dose clarithromycin.