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Porcine reproductive and respiratory syndrome virus (PRRSV) is an RNA virus that causes reproductive failure in sows and respiratory problems in piglets. PRRSV infection leads to substantial pig mortality and causing huge economic losses so that disease outbreaks caused by the new PRRSV strain from other regions have caused great concern in China. In this study, we analysed the pathogenicity of the novel ORF5 RFLP 1‐7‐4‐like PRRSV strain, named PRRSV‐ZDXYL‐China‐2018‐1 in pigs. The viral challenge test showed that PRRSV‐ZDXYL‐China‐2018‐1 infection can cause persistent fever, moderate dyspnoea, serum viraemia and interstitial pneumonia in piglets. The levels of viral loads in serum and PRRSV‐specific antigen were also detected in lung tissues were used one‐step Taq‐Man RT‐qPCR and Immunohistochemistry, respectively. At 28dpi, the level of specific antibodies was increased among infected piglets. Importantly, the new virus appeared be a moderately virulent isolate with pathogenicity compared to HP‐PRRSV strain LQ (JXA1‐like strain). Histological examination revealed severe monocyte haemorrhage and interstitial pneumonia associated with monocyte infiltration in the lung tissue of pigs infected with PRRSV‐ZDXYL‐China‐2018‐1 and LQ‐JXA1 strains. Immunohistochemistry (IHC) results showed positive brown‐red epithelial cells and macrophages in pig lungs. Therefore, it is critical to establish an effective strategy to control the spread of PRRSV in China. [ABSTRACT FROM AUTHOR]

Based on morphological, cytological and molecular data, a new species of Gesneriaceae, Petrocodon jiangxiensis F. Wen, L.F. Fu & L.Y. Su from Jiangxi Province, China, is described and illustrated. Morphologically, it resembles the most P. asterocalyx. Both species have axillary cymes, an actinomorphic calyx and similarly shaped corolla, but P. jiangxiensis can be easily distinguished by ovate-elliptic to broadly ovate leaf blades, three bracts with a crenulate to serrate margin, smaller calyx lobes 5–6 × ca. 1 mm, smaller corolla 1.7–2.3 cm long, and glabrous anthers. Petrocodon jiangxiensis has a 2n = 36 somatic chromosome number. [ABSTRACT FROM AUTHOR]

Boehmeria, as currently circumscribed, comprises 52 species and has a pantropical distribution. Liang et al. propose a sectional classification of Boehmeria based on the phylogenetic analysis of SNP data for 20 species and an additional 10 subspecific taxa of these at the rank of variety or form. They restrict their sampling to species documented in China. We found many shortcomings in the sampling and analyses which we feel have resulted in a misleading phylogeny for the genus and the economically important fibre-plant, Boehmeria nivea. By sampling only Chinese species of this genus for their in-group and using a single distantly related outgroup, Liang et al. have failed to capture the diversity of the genus and so erroneously concluded that it forms a monophyletic group. Previous published research clearly demonstrates that Boehmeria is paraphyletic and polyphyletic, comprising at least four monophyletic groupings most closely related to several genera within the Boehmerieae. For these reasons, the sections that Liang et al. (Ind Crops Prod 148:112092, 2020. https://doi.org/10.1016/j.indcrop.2020.112092) propose for Boehmeria are not effective tools for its classification. The important fibre-plant, Boehmeria nivea, should therefore not be considered as part of the genus Boehmeria for the purposes of crop breeding, but as sister to Archiboehmeria. Breeding programmes for ramie should therefore focus on populations and germplasm of Archiboehmeria atrata. We conclude that poor taxon sampling, overlooking relevant molecular and taxonomic literature, internal conflict within their SNP data and the overinterpretation of low support values has resulted in the erroneous conclusion that Boehmeria represents a monophyletic or 'natural' genus. [ABSTRACT FROM AUTHOR]

This study was the first report about complete chloroplast genome of Aster hypoleucus (Asteraceae, Astereae), an endemic species in Xizang (China). The circular whole cp genome of A. hypoleucus was 152,300 bp in length, contained a large single-copy (LSC) region of 84,031 bp and a small single-copy (SSC) region of 18,269 bp. These two regions were separated by a pair of inverted repeat regions (IRa and IRb), each of them 25,000 bp in length. A total of 134 functional genes were encoded, consisted of 89 protein-coding genes, 37 tRNA genes, and eight rRNA genes. The overall GC content of the chloroplast genome sequence was 37.3%, and the GC contents of the LSC, SSC, and IR regions were 35.2%, 31.2%, and 43.0%, respectively. [ABSTRACT FROM AUTHOR]

Petrocodon tongziensis R.B.Zhang & F.Wen, a new species from northern Guizhou province, China, is described and illustrated based on molecular and morphological evidence. The new species was found growing in crevices and on tufa of moist surfaces of limestone hills in Tongzi County. A maximum parsimony (MP) analysis based on the combined ITS and trnL‐F DNA regions showed that the new species falls within a large polytomy within Petrocodon, but is resolved as most closely related to an unidentified species (WF2014) and these two taxa are in turn resolved as sister to Petrocodon hunanensis X.L.Yu & Ming Li. This is congruent with the fact that both P. hunanensis and P. tongziensis have four fertile stamens, a character state likely to be an ancestral state distinguishing this clade from the rest of Petrocodon. Petrocodon tongziensis differs from P. hunanensis by lacking a terrestrial stem, as well as by the number of bracts, presence of bracteoles, shape of the lobes of the upper lip, and reduced number and length of staminodes. [ABSTRACT FROM AUTHOR]

The Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) cause a huge economic loss around the pig industry worldwide; the NADC30-like PRRSV have attracted much attention outbreaks in China in recent years. Recombination between PRRSV subtypes, point mutations, insertions and deletions that contribute to the emergence of new variants in the genome. In this study, the PRRSV-HB-16-China-2019 strain's full-length genomic sequence shares 93.0% nucleotide similarity to NADC30 PRRSV without any gene insertion. Compared with VR-2332, it has an NSP2 coding region that is different from NADC30, which has a discontinuous 206-aa (111-aa from position 323 to 433 and 95-aa from position 476 to 570) deletion. Compared with other NADC30-Like strains, it has a discontinuous 75-amino acid (75-aa from position 476 to 552) deletion, which was first reported. Notably, the strain, PRRSV-HB-16-China-2019, contained an addition a 1-aa deletion in ORF5 and a unique 3-nt deletion in 3′-UTR similar to NADC30, the strain is recombined between a NADC30-like strain and a vaccine strain named RespPRRS MLV(parental strain VR-2332). Our findings indicate that PRRSV-HB-16-China-2019 is a new NSP2-deletion NADC30-like strain with certain deletions and mutations. Our results show that the emergence of the new NADC30-like strain has increased the difficulty of PRRSV prevention in China. • The complete genomic sequence of a new NSP2-deletion isolated in Hebei Province, northern China. • Compared with other NADC30-Like strains, it has a discontinuous 75-amino acid (75-aa from position 476 to 552) deletion, which was first reported. • The PRRSV-HB-16-China-2019 strain was a recombination event between the NADC30-like strains (lineage 1) and RespPRRS MLV vaccine strain (lineage 5). [ABSTRACT FROM AUTHOR]

The outbreaks of fungal diseases in cultured fish have been severe in recent years, which is harmful to the healthy and sustainable development of fish farming. In this study, an investigation was conducted for significant fungal infections of 12 species of fish in four regions in Xinjiang, China, to understand the distribution of local fish fungal pathogens. Twenty-six fungal strains with pathogenicity were isolated, and the challenge experiment showed that eight strains from Changji area had high infection rate to fish eggs. Based on internal transcribed spacer sequence data and molecular analysis, the 26 strains were classified into nine different species of six fungal genera. Phylogenetic analysis showed that all strains were divided into two clades, namely Cluster 1 (contains only the genus Mucor) and Cluster 2 (consists of five small branches), and the distribution of strains from the same region was scattered in two clusters. There is no strict host selectivity for these fungi to infect fish. Mucor sp. are the main fungal pathogen of fish in these four regions, whereas Hypophthalmichthys molitrix and Carassius auratus are two types of fish that were susceptible to pathogen. In addition, the environmental adaptability experiments showed that eight highly pathogenic strains have different adaptability to the environment, and their optimum temperature and pH were 25°C and 7.0, respectively, whereas the concentration of NaCl was negatively correlated with the growth of strains. Therefore, these results indicated that the coinfection of multiple fungal pathogens in a culture region should be considered in the future study., (© 2021 Fisheries Society of the British Isles.)

Platelet function tests have been increasingly used to assist in the diagnosis of platelet disorders and prethrombotic state, monitoring of the efficacy of antiplatelet therapies, and personalized treatment. On the basis of light transmission aggregometry, new methods for platelet function test have been developed successively. At present, the research and development of platelet function detector is in its infancy in China. The active constituents of antiplatelet Chinese medicines can be classified into terpenoids, flavonoids, saponins, organic acids, lignans, diketones, volatile oils, and stilbenes. The results of dose-antiplatelet effect relationship of Chinese medicines and the active constituents showed that the effective concentration of the extracts or monomers of Chinese medicines was at micromolar level(μmol·L~(-1)), among which salvianolic acid B and ginkgolide K, ginkgolide B, and ginkgolide A had the strongest antiplatelet effect. These results suggest that the antiplatelet effect of Chinese medicine may be weaker than that of chemical drugs and biological products. Therefore, it is necessary to explore the structure-activity relationship of the active constituents in existing Chinese medicines and further improve their efficacy through structure modification. The antiplatelet effect of Chinese medicines and the constituents involves multiple pathways and multiple targets. These research results provide a reference for clinical application of them. However, there is still a lack of large-scale multi-center clinical trials to confirm the efficacy and safety of them. The regularity of the relationship between the structures of various constituents and their corresponding functions is still unknown and the relevant signal transduction pathways and structure-activity relationship need to be further studied. This paper summarized and analyzed the determination methods of platelet functions and the research results of antiplatelet Chinese medicines, which is of reference value for the research of effective and safe antiplatelet Chinese medicines.

Purpose: The purpose of this article is to study the effect of autologous platelet-rich plasma (PRP) injected into the upper cavity of the temporomandibular joint (TMJ) on the treatment of TMJ osteoarthritis., Patients and Methods: We retrospectively analyzed the data of 27 patients with TMJ osteoarthritis treated at the China Medical University Hospital of Stomatology from September 2018 to September 2019. Maximal interincisal opening, pain intensity, and TMJ sounds were recorded and compared before treatment and at the 3rd and 6th months after the treatment. SPSS 24.0 software was used to analyze the data of each group, and the imaging changes in the condylar bone were compared before and 6 months after the treatment. The P-value was set at .05., Results: Better results were observed in the group treated with PRP on maximal interincisal opening and pain intensity than in the group receiving chitosan treatment. Regarding TMJ sounds, relief was observed in both groups, with no significant difference., Conclusions: The effect of PRP on the improvement of the maximal interincisal opening and pain intensity of patients with TMJ osteoarthritis is better than that of chitosan. However, it should be noted that the incidence of complications associated with the injection of PRP may be higher than that with injection of chitosan., (Copyright © 2020 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

The porcine circovirus type 3 (PCV3) becomes an important causative agent of swine disease since its discovery in 2016. PCV3 infection exhibits a wide range of clinical syndromes causing substantial economic losses in swine industry. Previous studies have reported the detection of numerous known viruses including circovirus in mosquitoes. However, the transmission of PCV3 in field-caught mosquitoes remains largely unknown. This study aims to detect PCV3 infection in mosquitoes and analyze its genomic characteristics. Here, we performed a PCR to detect the PCV3 in 269 mosquito samples collected from pig farms located in Heilongjiang, Jilin, and Yunnan provinces. The proportion of PCV3-positive mosquitoes was 32.0 % (86/269), ranging from 21.4%-42.5% at farm level, which may imply that mosquito serves as a route of transmission for PCV3. To determine the possible origin of PCV3 in mosquitoes, 80 pig serum samples were collected from the pig farms where mosquito sampling was also performed. The proportion of PCV3-positive farms ranged from 15.0%-30.0 % in which infection of positive pigs positively correlated with mosquitoes carrying the virus. Additionally, we sequenced the entire genome of 6 strains of PCV3 in mosquitoes and 2 strains of PCV3 in pigs. Sequence analysis indicated a 100 % nucleotide similarity between mosquito and pig viral isolates that were all collected from similar farms. Phylogenetic analysis showed that PCV3 could be divided into two clades, PCV3a and PCV3b, and the PCV3 strains isolated in mosquitoes were distributed on the two clades. Our results demonstrate that mosquitoes may serve as a potential transmission vector in the life-cycle of PCV3, revealing possible transmission routes of PCV3., (Copyright © 2019 Elsevier B.V. All rights reserved.)

We analyzed 52 pollen samples of surface soils from the southern slope of western Tian-shan, China, to understand the relationship between the surface pollen and modern vegetation, and the significance of the Artemisia/Chenopodiaceae (A/C). The results showed that there were five vegetation zones from the mountain top to the foot, i.e., alpine desert zone, alpine meadow zone, meadow and steppe zone, mountain desert zone, and typical desert zone. The typical taxa were Artemisia, Chenopodiaceae, Poaceae and Ephedra. The surface pollen assemblages greatly differed across different vegetation zones in this area. Surface pollen in the southern slope of the western Tianshan Mountains was affected by the northern slope, with the impacts increasing with the increases of altitude. The A/C increased with altitude, peaked in the alpine meadow zone, and then decreased, which could effectively indicate the vertical moisture change. Given the great fluctuation of A/C value, when using this ratio to reconstruct climate and environment, attention should be paid to the fact that high values caused by human activities and other factors may lead to misjudgments.

Rice stripe virus (RSV) is one of the most economically important pathogens of rice and is repeatedly epidemic in China, Japan and Korea. The most recent outbreak of RSV in eastern China in 2000 caused significant losses and raised serious concerns. In this paper, we provide a genotyping profile of RSV field isolates and describe the population structure of RSV in China, based on the nucleotide sequences of isolates collected from different geographical regions during 1997-2004. RSV isolates could be divided into two or three subtypes, depending on which gene was analysed. The genetic distances between subtypes range from 0.050 to 0.067. The population from eastern China is composed only of subtype I/IB isolates. In contrast, the population from Yunnan province (southwest China) is composed mainly of subtype II isolates, but also contains a small proportion of subtype I/IB isolates and subtype IA isolates. However, subpopulations collected from different districts in eastern China or Yunnan province are not genetically differentiated and show frequent gene flow. RSV genes were found to be under strong negative selection. Our data suggest that the most recent outbreak of RSV in eastern China was not due to the invasion of new RSV subtype(s). The evolutionary processes contributing to the observed genetic diversity and population structure are discussed.