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Developing alternatives to antibiotics is an urgent need in livestock production. Antimicrobial peptides (AMPs) are regarded as powerful antibiotic substitutes (ASs) because AMPs have broad-spectrum antimicrobial activities and growth-promoting ability. Here, we aimed to comprehensively assess the effects of AMPs on the growth performance, diarrhea rate, intestinal morphology and immunity of healthy or challenged piglets, compared with an antibiotics group or negative control group. We performed a set of meta-analyses of feeding trials from database inception to 27 May 2019. Among the 1379 identified studies, 20 were included in our meta-analyses (56 arms and 4067 piglets). The meta-analyses revealed that (1) compared with the negative control group, AMPs significantly improved the healthy piglets’ average daily gain (ADG), average daily feed intake (ADFI), gain : feed ratio (G/F), levels of immune globulin (Ig) IgM and IgG, and intestinal villus height : crypt depth ratio (V/C) (P < 0.05). Meanwhile, AMPs significantly increased the challenged piglets’ ADG, ADFI, G/F and V/C of the jejunum and ileum, and notably deceased the diarrhea rate (P < 0.05); (2) compared with antibiotics group, the effects of AMPs were slightly weaker than those of antibiotics in the healthy piglets, but AMPs have similar effects to those of antibiotics in challenged piglets. In a higher purity, the optimal dose of AMPs may be approximately 0.01%. Our findings indicate that AMPs can improve piglet growth performance, enhance immunity, benefit intestinal morphology and decrease the diarrheal rate. AMPs could be great ASs especially under infection conditions.
In recent years, men who have sex with men (MSM) constitute a major group of HIV transmission in China. High primary drug-resistance (PDR) rate in MSM also represents a serious challenge for the Chinese antiretroviral therapy (ART) program. To assess the efficiency of ART in controlling HIV/AIDS infection among MSM, we developed a compartmental model for the annually reported HIV/AIDS MSM from 2007 to 2019 in the Zhejiang Province of China. R0 was 2.3946 (95% CI (2.2961–2.4881)). We predict that 90% of diagnosed HIV/AIDS individuals will have received treatment till 2020, while the proportion of the diagnosed remains as low as 40%. Even when the proportion of the diagnosed reaches 90%, R0 is still larger than the level of AIDS epidemic elimination. ART can effectively control the spread of HIV, even in the presence of drug resistance. The 90-90-90 strategy alone may not eliminate the HIV epidemic in Chinese MSM. Behavioural and biologic interventions are the most effective interventions to control the HIV/AIDS epidemic among MSM.
Chlamydia trachomatis (CT) infection has been a major public health threat globally. Monitoring and prediction of CT epidemic status and trends are important for programme planning, allocating resources and assessing impact; however, such activities are limited in China. In this study, we aimed to apply a seasonal autoregressive integrated moving average (SARIMA) model to predict the incidence of CT infection in Shenzhen city, China. The monthly incidence of CT between January 2008 and June 2019 in Shenzhen was used to fit and validate the SARIMA model. A seasonal fluctuation and a slightly increasing pattern of a long-term trend were revealed in the time series of CT incidence. The monthly CT incidence ranged from 4.80/100 000 to 21.56/100 000. The mean absolute percentage error value of the optimal model was 8.08%. The SARIMA model could be applied to effectively predict the short-term CT incidence in Shenzhen and provide support for the development of interventions for disease control and prevention.
Proximal environments could facilitate smoking cessation among low-income smokers by making cessation appealing to strive for and tenable.
We sought to examine how home smoking rules and proximal environmental factors such as other household members' and peers' smoking behaviors and attitudes related to low-income smokers' past quit attempts, readiness, and self-efficacy to quit.
This analysis used data from Offering Proactive Treatment Intervention (OPT-IN) (randomized control trial of proactive tobacco cessation outreach) baseline survey, which was completed by 2,406 participants in 2011/12. We tested the associations between predictors (home smoking rules and proximal environmental factors) and outcomes (past-year quit attempts, readiness to quit, and quitting self-efficacy).
Smokers who lived in homes with more restrictive household smoking rules, and/or reported having ‘important others’ who would be supportive of their quitting, were more likely to report having made a quit attempt in the past year, had greater readiness to quit, and greater self-efficacy related to quitting.
Adjustments to proximal environments, including strengthening household smoking rules, might encourage cessation even if other household members are smokers.
To investigate the morphology and dimensions of the vestibular aqueduct on axial, single-oblique and double-oblique computed tomography images.
The computed tomography temporal bone scans of 112 patients were retrospectively evaluated. Midpoint and opercular measurements were performed using axial, single-oblique and double-oblique images. Morphometric analyses were also conducted. The vestibular aqueduct sizes on axial, single-oblique and double-oblique images were compared.
At the midpoint, the mean (± standard deviation) vestibular aqueduct measured 0.61 ± 0.23 mm, 0.74 ± 0.27 mm and 0.82 ± 0.38 mm on axial, single-oblique and double-oblique images, respectively; at the operculum, the vestibular aqueduct measured 0.91 ± 0.30 mm, 1.11 ± 0.45 mm and 1.66 ± 1.07 mm on the respective images. The co-efficients of variation of the vestibular aqueduct measured at the midpoint were 37.4 per cent, 36.5 per cent and 47.5 per cent on axial, single-oblique and double-oblique images, respectively; at the operculum, the measurements were 33.0 per cent, 40.5 per cent and 64.5 per cent. Regarding morphology, the vestibular aqueduct was fissured (33.5 per cent), tubular (64.3 per cent) or invisible (2.2 per cent).
The morphology and dimensions of the vestibular aqueduct were highly variable among axial, single-oblique and double-oblique images.
Cucumber powdery mildew is a destructive foliar disease caused by Podosphaera xanthii (formerly known as Sphaerotheca fuliginea) that substantially damages the yield and quality of crops. The control of this disease primarily involves the use of chemical pesticides that cause serious environmental problems. Currently, numerous studies have indicated that some plant extracts or products potentially have the ability to act as natural pesticides to control plant diseases. It has been reported that turmeric (Curcuma longa L.) and its extract can be used in agriculture due to their insecticidal and fungicidal properties. However, the most effective fungicidal component of this plant is still unknown. In the current study, the crude extract of C. longa L. was found to have a fungicidal effect against P. xanthii. Afterwards, eight fractions (Fr.1–Fr.8) were gradually separated from the crude extract by column chromatography. Fraction 1 had the highest fungicidal effect against this pathogen among the eight fractions. The active compound, (+)-(S)-ar-turmerone, was separated from Fr 1 by semi-preparative high-performance liquid chromatography and identified based on its 1H nuclear magnetic resonance (NMR) and 13C NMR spectrum data. The EC50 value of (+)-(S)-ar-turmerone was found to be 28.7 µg/ml. The compound also proved to have a curative effect. This is the first study to report that the compound (+)-(S)-ar-turmerone has an effect on controlling this disease. These results provide a basis for developing a new phytochemical fungicide from C. longa L. extract.
Studies of schizophrenia at drug-naive state and on antipsychotic medication have reported a number of regions of gray-matter (GM) abnormalities but the reports have been inconsistent. The aim of this study was to conduct multimodal meta-analysis to compare the cross-sectional voxel-based morphometry studies of brain GM in antipsychotic-naive first-episode schizophrenia (AN-FES) and those with antipsychotic treatment within 1 year (AT-FES) to determine the similarities and differences in these groups. We conducted two separate meta-analyses containing 24 studies with a sample size of 801 patients and 957 healthy controls. A multimodal meta-analysis method was used to compare the findings between AN-FES and AT-FES. Meta-regression analyses were done to determine the influence of different variables including age, duration of illness, and positive and negative symptom scores. Finally, jack-knife analyses were done to test the robustness of the results. AN-FES and AT-FES showed common patterns of GM abnormalities in frontal (gyrus rectus), superior temporal, left hippocampal and insular cortex. GM in the left supramarginal gyrus and left middle temporal gyrus were found to be increased in AN-FES but decreased in AT-FES, whereas left median cingulate/paracingulate gyri and right hippocampus GM was decreased in AN-FES but increased in AT-FES. Findings suggest that both AN-FES and AT-FES share frontal, temporal and insular regions as common anatomical regions to be affected indicating these to be the primary regions of GM abnormalities in both groups.
A new approach is proposed to analyze Bremsstrahlung X-rays that are emitted from laser-produced plasmas (LPP) and are measured by a stack type spectrometer. This new method is based on a spectral tomographic reconstruction concept with the variational principle for optimization, without referring to the electron energy distribution of a plasma. This approach is applied to the analysis of some experimental data obtained at a few major laser facilities to demonstrate the applicability of the method. Slope temperatures of X-rays from LPP are determined with a two-temperature model, showing different spectral characteristics of X-rays depending on laser properties used in the experiments.
At the end of 2013, China reported a countrywide outbreak of measles. From January to May 2014, we investigated the clinical and immunological features of the cases of the outbreak admitted to our hospital. In this study, all 112 inpatients with clinically diagnosed measles were recruited from the 302 Military Hospital of China. The virus was isolated from throat swabs from these patients, and cytokine profiles were examined. By detecting the measles virus of 30 of the 112 patients, we found that this measles outbreak was of the H1 genotype, which is the major strain in China. The rates of complications, specifically pneumonia and liver injury, differed significantly in patients aged <8 months, 8 months to 18 years, and >18 years: pneumonia was more common in children, while liver injury was more common in adults. Pneumonia was a significant independent risk factor affecting measles duration. Compared to healthy subjects, measles patients had fewer CD4+IL-17+, CD4+IFN-γ+, and CD8+IFN-γ+ cells in both the acute and recovery phases. In contrast, measles patients in the acute phase had more CD8+IL-22+ cells than those in recovery or healthy subjects. We recommend that future studies focus on the age-related distribution of pneumonia and liver injury as measles-related complications as well as the association between immunological markers and measles prognosis.
The abundance and cross-linking of intramuscular connective tissue contributes to the background toughness of meat, and is thus undesirable. Connective tissue is mainly synthesized by intramuscular fibroblasts. Myocytes, adipocytes and fibroblasts are derived from a common pool of progenitor cells during the early embryonic development. It appears that multipotent mesenchymal stem cells first diverge into either myogenic or non-myogenic lineages; non-myogenic mesenchymal progenitors then develop into the stromal-vascular fraction of skeletal muscle wherein adipocytes, fibroblasts and derived mesenchymal progenitors reside. Because non-myogenic mesenchymal progenitors mainly undergo adipogenic or fibrogenic differentiation during muscle development, strengthening progenitor proliferation enhances the potential for both intramuscular adipogenesis and fibrogenesis, leading to the elevation of both marbling and connective tissue content in the resulting meat product. Furthermore, given the bipotent developmental potential of progenitor cells, enhancing their conversion to adipogenesis reduces fibrogenesis, which likely results in the overall improvement of marbling (more intramuscular adipocytes) and tenderness (less connective tissue) of meat. Fibrogenesis is mainly regulated by the transforming growth factor (TGF) β signaling pathway and its regulatory cascade. In addition, extracellular matrix, a part of the intramuscular connective tissue, provides a niche environment for regulating myogenic differentiation of satellite cells and muscle growth. Despite rapid progress, many questions remain in the role of extracellular matrix on muscle development, and factors determining the early differentiation of myogenic, adipogenic and fibrogenic cells, which warrant further studies.
Following the LAMOST Spectroscopic Survey and Xuyi's Photometric Survey of the Galactic anti-center (GAC), we plan to conduct a time-domain survey of GAC to study the variable sky using Nanshan 1m telescope. The survey will be conducted during winter (in Nov., Dec., and Jan.). The first goal of the survey is to cover 270 sq.deg. of sky area in three years. The survey intends to detect some strong transient events of stars and find some short time-scale variable stars of different types. In this paper, we introduce the survey and present the preliminary results already carried out.
The brown planthopper Nilaparvata lugens is a serious phloem-feeding pest of rice in China. The current study focuses on a saccharopine dehydrogenase (SDH) that catalyzes the penultimate reaction in biosynthesis of the amino acid lysine (Lys), which plays a role in insect growth and carnitine production (as a substrate). The protein, provisionally designated as NlylsSDH [a SDH derived from yeast-like symbiont (YLS) in N. lugens], had a higher transcript level in abdomens, compared with heads, wings, legs and thoraces, which agrees with YLS distribution in N. lugens. Ingestion of Nlylssdh targeted double-stranded RNA (dsNlylssdh) for 5, 10 and 15 days decreased the mRNA abundance in the hoppers by 47, 70 and 31%, respectively, comparing with those ingesting normal or dsegfp diets. Nlylssdh knockdown slightly decreased the body weights, significantly delayed the development of females, and killed approximately 30% of the nymphs. Moreover, some surviving adults showed two apparent phenotypic defects: wing deformation and nymphal cuticles remained on tips of the legs and abdomens. The brachypterours/macropterours and sex ratios (female/male) of the adults on the dsRNA diet were lowered compared with the adults on diets without dsRNA. These results suggest that Nlylssdh encodes a functional SDH protein. The adverse effect of Nlylssdh knockdown on N. lugens implies the importance of Lys in hopper development. This study provides a proof of concept example that Nlylssdh could serve as a possible dsRNA-based pesticide for planthopper control.
A cylindrical-shaped micropillar array embedded microfluidic device was proposed to enhance the dispersion of cell clusters and the efficiency of single cell encapsulation in hydrogel. Different sizes of micropillar arrays act as a sieve to break Escherichia coli (E. coli) aggregates into single cells in polyethylene glycol diacrylate (PEGDA) solution. We applied the external force for the continuous breakup of cell clusters, resulting in the production of more than 70% of single cells into individual hydrogel particles. This proposed strategy and device will be a useful platform to utilize genetically modified microorganisms in practical applications.
We developed a tunnel-current based identification method by using nano-gap integrated devices. We performed electrical measurements for mono-nucleotide and oligo-nucleotide during its translocation of molecules between the nano-gap. Based on this determined electrical conductivity for single-nucleotides, we electrically identify the base-type in oligonucleotides, and found that this time-profiles represents the molecular translocation behaviors inside nano-gap. This method could be a promising for an electrical nucleotide sequencing methodology with label-free, high-speed, and low-cost.
A dual experimental and numerical top-down approach is applied to investigate the link between osteocyte morphology and mechanical perception of their environment at the progenitor and mature stages. The numerical model is based on explicit tissue morphology discretization to identify bone diffuse damage at the cellular scale. The in vitro experimental model presents a live allograft bone system where a patient progenitor or mature osteocytes were reseeded in fresh human donor cortical bone tissues subjected to mechanical loading. The live systems behaved mechanically as fresh bone and the cells spatially reorganized in vitro as in vivo. The system under mechanical load also showed an adaptation of the calcium membrane transport rate to the expected in vivo mechanical load detected by bone cells at different stages of differentiation.
The very synthesis of functional microparticles is generally deemed the most necessary, but obviously not the only step in successful product development. The behavior of obtained microparticles has to be tested in environments resembling the end use conditions to ensure the desired functionality. During the testing, various problems concerning particles behavior can arise, e.g. unwanted adhesion (before the successful delivering of particles to the region of interest, they will adhere somewhere else, thus hindering the delivery of transported substance), insufficient adhesion (in cases, when the particle adhesion is desired, e.g. specific adhesion for targeted delivery, the end amount of adhered particles might not be sufficient for reaching the expected concentration of released substance, meaning adhesion is not strong enough under given conditions) or particle breakage (some particles are of more fragile structure, which can result in condition limitations, in which they can exist without damage). Furthermore, regarding specific adhesion, the demonstration of such particle functionality should also be performed before testing on living organisms, preferably in conditions resembling the end use.
Breast cancer (BrCa) is the second commonest cause of cancer-related deaths in women. The metastatic breast cancer exhibits a high affinity to bone, leading to debilitating skeletal complications associated with significant morbidity and poor prognosis. Traditional in vitro and in vivo BrCa bone metastasis models contain many inherent limitations with regards to controllability, reproducibility, and flexibility of design. Thus, the objective of this research is to use a 3D bioprinting system and nanomaterials to recreate a biomimetic and tunable bone model suitable for the effective simulation and study of metastatic BrCa invading and colonizing a bone environment. For this purpose, we designed and 3D printed a series of scaffolds, comprised of a bone microstructure and nano hydroxyapatites (nHA, inorganic nano components in bone). The size and geometry of the bone microstructure was varied with 250 and 150 µm pores, in repeating square and hexagon patterns, for a total of four different pore geometries. 3D bioprinted scaffolds were subsequently conjugated with nHA, using an acetylation chemical functionalization process and then characterized by scanning electron microscope (SEM). SEM imaging showed that our designed microfeatures were printable with the predesigned resolutions described above. Imaging further confirmed that acetylation effectively attached nHA to the surface of scaffolds and induced a nanoroughness. Metastatic BrCa cell 4 h adhesion and 1, 3 and 5 day proliferation were investigated in the bone model in vitro. The cell adhesion and proliferation results showed that all scaffolds are cytocompatible for BrCa cell growth; in particular the nHA scaffolds with small hexagonal pores had the highest cell density. Given this data, it can be stipulated that our 3D printed nHA scaffolds may make effective biomimetic environments for studying BrCa bone metastasis.