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Avian leukemia is an infectious tumorous disease of chickens caused by subgroup A of the avian leukemia virus (ALV-A), which mainly causes long-term viremia, slow growth, immune suppression, decreased production performance, multi-tissue tumors, and even death. The infection rate of this disease is very high in chicken herds in China, causing huge economic losses to the poultry industry every year. We successfully expressed the specific antigen protein of ALV (P27) through recombinant protein technology and screened a pair of highly sensitive monoclonal antibodies (mAbs) through mouse immunity, cell fusion, and antibody pairing. Based on this pair of antibodies, we established a dual antibody sandwich ELISA and gold nanoparticle immunochromatographic strip (AuNP-ICS) detection method. In addition, the parameters of the dual antibody sandwich ELISA and AuNP-ICS were optimized under different reaction conditions, which resulted in the minimum detection limits of 0.2 ng mL−1 and 1.53 ng ml−1, respectively. Commonly available ELISA and AuNP-ICS products on the market were compared, and we found that our established immune rapid chromatography had higher sensitivity. This established AuNP-ICS had no cross-reactivity with Influenza A (H1N1), Influenza A (H9N2), respiratory syncytial virus (RSV), varicella-zoster virus (VZV), Listeria monocytogenes listeriolysin (LLO), and Staphylococcal enterotoxin SED or SEC. Finally, the established AuNP-ICS was used to analyze 35 egg samples, and the results showed 5 positive samples and 30 negative samples. The AuNP-ICS rapid detection method established by our group had good specificity, high sensitivity, and convenience, and could be applied to the clinical sample detection of ALV-A. [ABSTRACT FROM AUTHOR]

Malus sieversii (Ldb.) Roem. is the original species of modern cultivated apple and a key national essential conservation plant in China. In recent years, degradation and death of wild apple has been exacerbated by imbalances in the rhizosphere micro-ecosystems of wild apple forests due to soil nutrient loss, grazing, climate change and pest and disease outbreaks. However, the structure, diversity and response to environmental factors of wild apple rhizosphere microbial communities are so far unclear. In this study, the rhizosphere bacterial and eukaryotic communities of M. sieversii (Ldb.) Roem. in eight regions of the Yili River were analyzed using 16S/18S rDNA high-throughput sequencing technology. The results indicated that the bacterial operational taxonomic units (OTUs), Shannon index, and community composition were significantly lower in regions A, E, and F than in other regions. By contrast, the dominant eukaryotic communities in all regions were relatively similar in composition and differed less than the relative abundance of bacterial communities. Geographical and climatic distance were found to be key factors influencing the composition and diversity of wild apple rhizosphere microbial communities through mantel analysis. Moreover, these factors above were more correlated with bacterial diversity than with eukaryotes. This study identified the structure of wild apple rhizosphere microbial communities in Xinjiang and their interaction mechanisms under geographical and environmental gradients. It provides guidance for the sustainable management and ecological construction of wild apple forests in China. [ABSTRACT FROM AUTHOR]

Simple Summary: Porcine reproductive and respiratory syndrome, caused by the porcine reproductive and respiratory syndrome virus, is considered one of the most devastating swine diseases worldwide. Porcine reproductive and respiratory syndrome virus 1 was first isolated in China in 2006, and there have been few reports concerning its genetic characteristics in China. We hope to find out the regularity of genetic diversity, recombination, and evolution of the virus by analyzing all available genomic sequences during 1991–2018. We found that high-frequency recombination regions were concentrated in non-structural protein 2 and structural proteins 2 to 4 and extensive deletions in non-structural protein 2; phylogenetic analysis revealed four independent introductions in China. Our results suggest that attention should be paid to the prevention and control of porcine reproductive and respiratory syndrome virus 1 and the rational use of vaccine strains. These results will help us to understand the recombination of porcine reproductive and respiratory syndrome virus and strengthen viral inspection before mixing herds of swine to reduce the probability of novel recombinant variants. Moreover, our study might form the basis of monitoring and control measures to prevent the spread of this economically important virus. Porcine reproductive and respiratory syndrome (PRRS), caused by the PRRS virus (PRRSV), is considered one of the most devastating swine diseases worldwide. PRRSV-1 was first isolated in China in 2006. However, there were few reports concerning the genetic characteristics of PRRSV-1 in China. In this study, three PRRSV-1 strains (HL85, HeB3, and HeB47) were detected by a general RT-qPCR method from clinical samples in 2018. HeB47 was identified as a recombinant between the BJEU06-1 and CReSA228-like strains. To further analyze the recombination and deletion features of PRRSV-1, all the available 88 complete genome sequences (isolated in 19 countries) from 1991 to 2018 in GenBank were analyzed. The high-frequency recombination regions were concentrated in NSP2 and GP2 to GP4. More importantly, phylogenetic analysis of PRRSV-1 revealed four independent introductions in China. Therefore, it is necessary to strengthen the important monitoring of breeding pigs and pork products and epidemiological surveys on pig farms to prevent the further spread of PRRSV-1. [ABSTRACT FROM AUTHOR]

The purposes of this study were to provide palynological information about apricots and to reveal the relationships among six ecological groups of apricots by describing the morphological characteristics of their pollen. The pollen grains of 175 accessions belonging to three species (Prunus armeniaca L., Prunus sibirica L., and Prunus mume Sieb. et Zucc.) of Prunus were examined using light microscopy and scanning electron microscopy. The pollen grains were isopolar monads, radially symmetric, medium to large in size, prolate or subprolate, and 3-colporate. Most pollen grains exhibited striate exine ornamentation, and a few exhibited striato-reticulate or cerebroid exine ornamentation. Cluster analysis divided the six ecological groups into two groups: one including the Central Asian, North China, and Dzhungar-Ili ecological group accessions and another including the Northeast Asian, European, and East China ecological group accessions. Principal component analysis revealed that equatorial diameter, colpus length, colpus width, and ridge width were the most important metrical pollen traits, and can be used as powerful diagnostic characters in apricot identification. We speculated that the cultivated apricots in Xinjiang were domesticated from wild apricots from the Ili Valley. This study describes the morphological characteristics of apricot pollen grains and provides some morphological information for future studies on the phylogenetic relationships of apricots. [ABSTRACT FROM AUTHOR]

In this study, a gold immunochromatographic assay (GICA) based on a penicillin receptor protein (PBP) is proposed to simultaneously detect penicillin, cephalosporin, and carbapenem antibiotics in milk and chicken. A mutant PBP, carboxy-terminal of the β-lactam sensor-transducer protein (BlaR-CTD, I188KS19CG24C) from Bacillus licheniformis ATCC14580 was expressed in E. coli as a soluble His-tag fusion protein. The purified BlaR-CTD mutant was labeled with colloidal gold (CG-BlaR-CTD-M) and applied to develop GICA. The GICA method was performed based on a competitive form, where the binding of the ampicillin-bovine serum albumin conjugate (Amp-BSA) to CG-BlaR-CTD-M was inhibited by free β-lactams in samples. The performance of the assay was confirmed by analysis of milk and chicken samples. The limits of detection of 21 β-lactam antibiotics met the maximum residue limits set by the European Union and China. The GICA gave results within 10 min, thus providing a rapid and reliable method for the on-site detection of multiple β-lactams in milk and chicken samples. [ABSTRACT FROM AUTHOR]

The Xianshuihe fault (XSHF) zone, characterized by intense tectonic activity, is located at the southwest boundary of the Bayan Har block, where several major earthquakes have occurred, including the 2008 Wenchuan and the 2013 Lushan earthquakes. This study analysed underground temperature sequence data for four years at seven measuring points at different depths (maximum depth: 18.9 m) in the southeastern section of the XSHF zone. High-frequency atmospheric noise was removed from the temperature sequences to obtain relatively stable temperature fields and heat fluxes near the measurement points. Our measurements show that the surrounding bedrock at (the seven stations distributed in the fault zone) had heat flux values range from −41.0 to 206 mW/m2, with a median value of 54.3 mW/m2. The results indicate a low heat flux in the northern section of Daofu-Kangting and a relatively high heat flux in the southern section of Kangting, which is consistent with the temperature distributions of the hot springs near the fault. Furthermore, our results suggest that the heat transfer in this field results primarily from stable underground heat conduction. In addition, the underground hydrothermal activity is also an obvious factor controlling the geothermal gradient. [ABSTRACT FROM AUTHOR]

Tectonic activities are accompanied with material movement and energy transfer, which definitely change the state of thermal radiation on the ground. Thus it is possible to infer present-day tectonic activities based on variations of the thermal radiation state on the ground. The received satellite infrared information is, however, likely influenced by many kinds of factors. Therefore, the first problem that needs to be solved is to extract information on tectonic activities and eliminate effects of external (non-tectonic) factors. In this study, we firstly make a review of the current studies on this subject, and then present the technical approach and our research goal. Using the data of 20 years from the infrared band of the satellite of National Oceanic and Atmospheric Administration (NOAA) and the method we have developed, we investigate fault activities in western China. The results show that the areas with high residual values of land surface brightness temperature (LSBT), which is presumably related to faultings in space, accord usually with the locations of followed major earthquakes. The times of their value growing are also roughly consistent with the beginning of active periods of earthquakes. The low frequency component fields of the LSBT, acquired from wavelet analysis, exhibit well the spatial distributions of active faults. The "heat penetrability index" (HP1) related with enhancement of subsurface thermal information has been expressed well for the backgrounds of accelerated tectonic motions, and some correlations exist between HP! and the local faulting and seismicity. This study provides a new approach to study temporal-spatial evolution of recent activities of faults and their interactions. [ABSTRACT FROM AUTHOR]

Importance: Asian patients undergoing cosmetic rhinoplasty often want surgeons to concentrate on the broad nasal tip. Modifying the cartilage framework is considered to be the fundamental strategy; during the modification procedures, the cephalic portion of the lower lateral cartilage is often excised and discarded. However, given the supporting function and volumetric filling properties of autologous cartilage, the cephalic cartilage should and can be salvaged by using our cruciate overlap technique., Objectives: To introduce a novel technique in modification of broad nasal tip in Asian patients undergoing rhinoplasty and assess its efficacy and safety., Design, Setting, and Participants: Dissection of 5 fresh cadaver head specimens was performed and the plausibility and reliability of the new procedure were determined at Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College. In addition, the cruciate overlap technique was performed in 43 Chinese patients between January 1, 2011, and December 31, 2013, and the surgical results were assessed subjectively and objectively during the follow-up period, ranging from 12 to 36 months, with the final follow-up November 30, 2014. Anthropometric measurements of patients' noses preoperatively and postoperatively were taken and the patients' complications were reviewed., Main Outcomes and Measures: Cadaveric evaluation, subjective and objective assessments of the surgical results (rated on a scale of 1 to 4, with 4 indicating much improvement from the preoperative level), nasal measurements of the patients, and evaluation of the complications., Results: The mean size of the cartilaginous flap in the cruciate overlap technique was 12.0 mm long and 3.0 mm wide, allowing for 180° rotation and graft coverage, with the nasal cartilage framework protected from collapse. Mean (SD) scores for the subjective and objective judgment of the outcomes were 3.3 (0.4) and 3.5 (0.3), respectively. Moreover, nasal measurements demonstrated significant postoperative improvement by increasing the mean nasal tip protrusion (from 14.3 [1.5] to 16.7 [2.0] mm) and reducing the mean tip width (from 22.7 [1.7] to 18.2 [1.6] mm) and tip angle (from 101.0° [6.3°] to 87.7° [6.7°]) (all P < .001). Acceptable ranges of edema, ecchymosis, and pain were observed in the early postoperative period and resolved within a short period. No aesthetic or functional adverse effects were reported during the follow-up period., Conclusions and Relevance: The cruciate overlap technique is an efficacious and reliable alternative for modification of broad nasal tips in Asian patients undergoing rhinoplasty., Level of Evidence: 4.

Background: Cleft palate is one of the most common congenital malformations in the maxillofacial region. After a cleft palate repair, surgeons must deal with the transverse growth restriction and palatal fistulas caused by scar tissue on the raw bone surface around the hard palate. This report describes the technique of the buccinator musculomucosal flap procedure performed together with repair of the cleft palate. The objective is to cover exposed bone areas of the hard palate to decrease scar contraction and subsequent transverse maxillary growth restriction, as well as tension at the closure., Methods: From August 2009 to February 2012, 15 patients underwent the buccinator musculomucosal flap procedure. First, the cleft palate was repaired by mucoperiosteal flaps, resulting in wide and raw bone surfaces around the hard palate. The outline of the flap was marked on the buccal mucosa. Grounding on the exposed bone areas around the hard palate, the authors designed widths of flaps ranging from 1.5 to 2.5 cm. These flaps were elevated from the buccopharyngeal fascia and turned 90° to cover the raw hard palate bone surfaces. The donor sites were closed by direct suture., Results: The follow-up period was 1-26 months (average, 10 months). No complications were found in any patient who underwent the procedure, and no fistulas occurred in the midline of the palate. No patients experienced complications related to the donor sites. No trismus or other dysfunction related to mouth movement was observed., Conclusions: The buccinator musculomucosal flap is a convenient and safe flap procedure with fewer donor-site complications. This procedure also has significant potential for improving maxilla growth and reducing the secondary complications that often can result from cleft palate repair., Level of Evidence Iv: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Background: The objective of this study is to established evidence of the existence of a novel member of the hepadnavirus family endemic in swine. Temporarily this virus was designated as swine hepatitis B virus (SHBV). This SHBV can be detected by using human hepatitis B virus diagnostic kits including ELISA, immunohistochemical staining, and transmission electron microscopy (TEM). Also seroprevalence of pig farms in Beijing, China, and pathological features of SHBV infection was determined., Results: Screened result shows that overall prevalence of HBsAg was 24.8%, closed to that of anti-HBsAg, whereas HBeAg and anti-HBe were barely detectable. The distribution of HBsAg and HBcAg was examined by immunohistochemistry of liver samples. Typical hepatitis pathological change, such as spotty parenchymal cell degeneration, necrosis of hepatocytes and proliferation of fibrous connective tissue were observed during histopathological analysis. Analysis of HBsAg-positive serum with TEM revealed two morphologic forms, 20 nm and 40 nm sized particles, similar to small spherical and Danes particles of HBV. Observation of the ultrastructure of the liver also found HBV-like particles in the nucleus of hepatocytes., Conclusion: Our research result implies that SHBV could be a causative agent of swine. The discovery of SHBV will unveil novel evolutionary aspects of hepatitis and provides new information for further hepadnavirus research.