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Reservoir properties and shale gas potential of the Upper Jurassic continental shales from the Mohe Foreland Basin were investigated based on organic geochemical analysis, X‐ray diffraction, scanning electron microscopy, low pressure nitrogen adsorption, high pressure mercury injection, and porosity and permeability analyses. The results indicate that the shallow lacustrine shales of the Emuerhe Formation are characterized by high total organic carbon content (0.43–22.83 wt.%), low hydrocarbon generative potential (less than 5.0 mg HC/g rock), type II kerogen, and a moderate thermal maturity stage (Ro of 1.05–1.46%). The inorganic pores dominate the pore system, and pores associated with clay minerals largely contribute to the surface area. The inorganic pore‐dominated lacustrine shale reservoir is characterized by dense, low porosity, and poor connectivity. The shales of the Emuerhe Formation show strong heterogeneity in mineralogy and are relatively enriched in clay minerals (33–66 wt.%). Due to the lack of biogenic silica, the effect of brittle minerals on hydraulic stimulation is ambiguous in the shallow lacustrine shales. The widely distributed, extensionally unfilled fractures can not only enhance hydrocarbon storage and migration capacity, but also play an important role in the generation of artificial reservoir fracturing. The pore network of lacustrine shales contributed by inorganic pores and unfilled micro‐fractures could also generate a relatively high porosity and permeability. The high‐mature thick shales in the northwest area of the Xingan Town would be the favourable zone for the shale gas exploration and exploitation in the Mohe Foreland Basin. [ABSTRACT FROM AUTHOR]

We previously reported a possible potyvirus isolated from Mirabilis jalapa that exhibited a high degree of sequence similarity to Basella rugose mosaic virus (BaRMV) in the region encoding the coat protein (CP). Here, we present the complete genome sequence of this isolate, comprising a 9666-nucleotide-long monopartite ssRNA (excluding the poly(A) tail) encoding a 3080-amino-acid polyprotein. The CP region showed a high degree of nucleotide sequence similarity to three BaRMV isolates (75.2–77.3% identity), while other regions showed nucleotide sequence identity values (48.8–73.7%) below the species demarcation threshold proposed by the ICTV. Therefore, we propose that this isolate be considered a new member of the genus Potyvirus, tentatively named "mirabilis crinkle mosaic virus" (MiCMV). [ABSTRACT FROM AUTHOR]

Background: Blastocystis is one of the most common intestinal parasites in humans and animals worldwide. At least 17 subtypes have been identified in mammals and birds. In China, although some studies have reported the occurrence of Blastocystis in humans and animals, our understanding of the role of animals in the transmission of human blastocystosis is only superficial due to a paucity of available molecular data. The aim of the present study was to understand infection rates of Blastocystis and the distribution and genetic diversity of subtypes in various mammal and bird species in northeastern China, as well as to assess the zoonotic potential of Blastocystis isolates. Methods: A total of 1265 fresh fecal specimens (1080 from ten mammal species and 185 from eight bird species) were collected in Heilongjiang, Liaoning and Jilin provinces of China. Each specimen was examined for the presence of Blastocystis by PCR amplification and sequence analysis of the partial SSU rRNA gene. Results: Fifty-four specimens (4.3%) were positive for Blastocystis. Birds (7.0%) had a higher infection rate of Blastocystis than mammals (3.8%). Blastocystis was found in seven mammal species, reindeer (6.7%), sika deer (14.6%), racoon dogs (7.5%), Arctic foxes (1.9%), dogs (2.9%), rats (3.7%) and rabbits (3.3%), as well as three bird species, pigeons (2.1%), chickens (13.0%) and red crowned cranes (14.0%). Eight subtypes were identified including ST1 (n = 5), ST3 (n = 3), ST4 (n = 13), ST6 (n = 8), ST7 (n = 6), ST10 (n = 13), ST13 (n = 4) and ST14 (n = 2). 64.8% (35/54) of Blastocystis isolates belonged to potentially zoonotic subtypes. Conclusions: To our knowledge, this is the first report of Blastocystis in reindeer (ST10 and ST13), rabbits (ST4), racoon dogs (ST3) and Arctic foxes (ST1, ST4 and ST7). The findings of potentially zoonotic subtypes suggest that the animals infected with Blastocystis might pose a threat to human health. These data will improve our understanding of the host range and genetic diversity of Blastocystis, and also help develop efficient control strategies to intervene with and prevent the occurrence of human blastocystosis in the investigated areas. [ABSTRACT FROM AUTHOR]

• A one-step RT-LAMP assay was developed for the detection of maize yellow mosaic virus (MaYMV). • The MaYMV detection limit in the RT-LAMP assay was 1 pg of plant total RNA template in a 10 μL reaction volume, which was 100 times more sensitive than that of the corresponding RT-PCR assay. • The optimized RT-LAMP assay successfully detected MaYMV using rapidly extracted crude RNA from MaYMV-infected maize as a template. • The RT-LAMP assay did not cross-react with any of the maize-infecting virus families tested. Maize is one of the most widely cultivated cereal crops worldwide. Maize yellow mosaic virus (MaYMV) (species Maize yellow mosaic virus, genus Polerovirus and family Luteoviridae) was first reported in maize from China. In this study, a one-step reverse-transcription loop-mediated isothermal amplification (RT-LAMP) assay was developed for detecting MaYMV. The optimal concentrations of betaine, Mg2+ and dNTPs for the assay were 0 M, 1.4 mM and 6 mM, respectively, and the optimal reaction time was 50 min. Using total plant RNA as the template, the detection limit of the RT-LAMP assay for MaYMV was 1 pg, while that of RT-PCR was 100 pg, indicating that the RT-LAMP assay developed was 100 times more sensitive than RT-PCR. Importantly, the RT-LAMP assay successfully detected MaYMV using rapidly extracted crude RNA from infected maize as a template. In conclusion, the RT-LAMP assay developed was a rapid, specific, sensitive and low-cost method for the detection of MaYMV in field samples of maize. [ABSTRACT FROM AUTHOR]

• A multiplex RT-PCR assay for MCMV, SCMV, MaYMV and MATV was developed for the early field detection of co-infections of these viruses in maize. • The detection limits of the multiplex RT-PCR assay for MaYMV and MCMV were 100 pg of cDNA template and those for MATV and SCMV were 1 ng cDNA template. • To validate the reliability of this multiplex RT-PCR assay, 138 maize samples from China were tested using this method and both single and co-infections were detected. Maize lethal necrosis disease (MLND) is a serious disease of worldwide importance. It is caused by the co-infection of maize with maize chlorotic mottle virus (MCMV) and a potyvirus, such as sugarcane mosaic virus (SCMV), that acts synergistically to produce more severe symptoms and production losses. More recently, maize yellow mosaic virus (MaYMV) and maize-associated totivirus (MATV) were found to co-infect with MCMV and SCMV in maize plants. To facilitate the detection of these viruses in co-infected maize, a multiplex RT-PCR assay was developed in this study. The assay used five specific primer pairs and simultaneously amplified these four viruses as well as the elongation factor 1α (EF 1α) gene use as internal control in one tube. The concentration of the primers, annealing temperature, annealing time, extension time and amplification cycles were optimized for the multiplex RT-PCR. The detection limit of the assay was up to 100 pg of total cDNA template. This multiplex RT-PCR assay was shown to be a sensitive and effective tool for the screening of field samples for the presence of these viruses in co-infected maize. [ABSTRACT FROM AUTHOR]

Mirabilis crinkle mosaic virus (MiCMV) was tentatively classified as a new member of the genus Potyvirus in the family Potyviridae in 2019. However, it was considered to be basella rugose mosaic virus based on the sequence similarity of the coat protein (CP) region. In this study, infectious MiCMV cDNA clones under the control of the 35S promoter were constructed with an In-Fusion cloning method. Systemically infected leaves of Mirabilis jalapa and Nicotiana benthamiana plants inoculated with pMiCMV and pMiCMV-NIb/eGFP had mosaic symptoms by 5 dpi. Infections were confirmed by a western blot analysis, electron microscopy, RT-PCR, and the inoculation of N. benthamiana seedlings with progeny virions. Systemic infections were not observed after Nicotiana glutinosa leaves were similarly inoculated, with eGFP fluorescence detected only in the inoculated leaves. Interestingly, the symptoms induced by pMiCMV and pMiCMV-NIb/eGFP were not similar to those caused by the wild-type MiCMV in Basella rubra plants. Moreover, RT-PCR analyses of B. rubra plants with virus-specific primers (MicpF and MicpR) indicated that a non-target fragment corresponding to the MiCMV CP coding region was amplified. This is the first report of the construction of a biologically active, full-length cDNA copy of the MiCMV RNA genome., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Multilocus sequence typing (MLST) tools have been used widely to characterize population genetic structure of some Cryptosporidium species. To understand MLST subtypes and population genetic structure of Cryptosporidium cuniculus from rabbits in Heilongjiang Province, China, 34 C. cuniculus DNA specimens were collected including VbA21 (n = 6), VbA28 (n = 2), VbA29 (n = 18) and VbA32 (n = 8). They were analyzed by nested-PCR amplification and sequencing at seven microsatellite, minisatellite and polymorphic loci including CP47, CP56, ML2, DZ-HRGP, MSC6-5, MSC6-7 and RPGR. The CP47, CP56, MSC6-5 and MSC6-7 loci were monomorphic. The remaining loci were polymorphic, with two, three and two subtypes being found at ML2, DZ-HRGP and RPGR loci, respectively. Six MLST subtypes were obtained based on sequence information of 29 DNA specimens successfully amplified at all eight loci including gp60 locus. Linkage disequilibrium (LD) analysis showed a clonal population structure of C. cuniculus in the investigated areas. STRUCTURE, neighbor-joining and network analyses indicated the presence of two distinct groups, corresponding to VbA21 subtype and VbA28, VbA29 and VbA32 subtypes. This is the first report of MLST analysis of C. cuniculus. A clonal population structure of C. cuniculus suggested the prevalence of C. cuniculus in Heilongjiang Province is not attributed to the introduction of rabbits. Thus, prevention and control strategies should be focused on making stricter measures to avoid occurrence of cross-transmission and re-infection among rabbit individuals. Based on the previous findings of VbA21 subtype only in rabbits and VbA28, VbA29 and VbA32 subtypes both in rabbits and humans, the results of subpopulation analyses might be used to assess zoonotic potential of C. cuniculus subtypes in Vb family. These data will be helpful to explore source attribution of infection/contamination of C. cuniculus and understand its transmission dynamics in humans and rabbits in the investigated areas., (Copyright © 2018. Published by Elsevier B.V.)

Background: Cryptosporidium spp. and Enterocytozoon bieneusi are prevalent zoonotic pathogens responsible for the high burden of diarrheal diseases worldwide. Rodents are globally overpopulated and are known as reservoirs or carriers of a variety of zoonotic pathogens including Cryptosporidium spp. and E. bieneusi. However, few data are available on genetic characterizations of both pathogens in rodents in China. The aim of the present work was to determine the prevalence and genetic characterizations of Cryptosporidium spp. and E. bieneusi in brown rats (Rattus norvegicus) from Heilongjiang, China., Methods: A total of 242 wild brown rats were captured in Heilongjiang Province of China. A fresh fecal specimen was collected directly from the intestinal and rectal content of each brown rat. All the fecal specimens were examined for the presence of Cryptosporidium spp. and E. bieneusi by PCR and sequencing of the partial small subunit (SSU) rRNA gene and the internal transcribed spacer (ITS) region of the rRNA gene of the two pathogens, respectively., Results: The infection rate was 9.1% (22/242) for Cryptosporidium spp. and 7.9% (19/242) for E. bieneusi. Sequence analysis confirmed the presence of C. ubiquitum (1/22, 4.5%) and three genotypes of Cryptosporidium, including Cryptosporidium rat genotype I (14/22, 63.6%), Cryptosporidium rat genotype IV (6/22, 27.3%) and Cryptosporidium suis-like genotype (1/22, 4.5%). Meanwhile, two E. bieneusi genotypes were identified, including D (17/19, 89.5%) and Peru6 (2/19, 10.5%)., Conclusions: To the best of our knowledge, Enterocytozoon bieneusi genotype Peru6 was identified in rodents for the first time globally and Cryptosporidium rat genotype I and Cryptosporidium rat genotype IV were found in rats in China for the first time. The finding of zoonotic C. ubiquitum and C. suis-like genotype, as well as E. bieneusi genotypes, suggests that brown rats pose a threat to human health. It is necessary to control brown rat population in the investigated areas and improve local people's awareness of the transmission risk of the two pathogens from brown rats to humans.

Enterocytozoon bieneusi is the most frequently diagnosed microsporidian species in humans and is also found in a wide range of animals. It is considered to be an important but neglected zoonotic pathogen. With the development of deer bred in captivity, the number of deer has been increasing in recent years in China and there are more people involved in this work. The aims of this study were to determine prevalence and genotypes of E. bieneusi in red deer (Cervus elaphus) and Siberian roe deer (Capreolus pygargus), and to assess their potential zoonotic transmission. A total of 122 fecal specimens were collected from 104 red deer and 18 roe deer from three deer farms in Heilongjiang and Jilin Provinces, China. Enterocytozoon bieneusi was detected and genotyped by PCR and sequencing of the internal transcribed spacer (ITS) region of the rRNA gene. The average infection rate was 8.2% (10/122), with 7.7% (8/104) for red deer and 11.1% (2/18) for roe deer. Two genotypes were identified: a known genotype BEB6 (n = 9) and a novel genotype named HLJD-VI (n = 1). This is the first report of E. bieneusi infection in Siberian roe deer. The fact that genotype BEB6 was detected previously in one human case of microsporidiosis, and that genotype HLJD-VI fell into zoonotic group 1, suggest the possibility of transmission to humans. A brief review of E. bieneusi genotypes in deer worldwide shows that 40 genotypes have been found in seven deer species, with genotype BEB6 being predominant., (© W. Zhao et al., published by EDP Sciences, 2017.)

In preparation for the introduction of human papillomavirus (HPV) vaccine, we investigated awareness and knowledge of HPV/HPV vaccine and potential acceptability to HPV vaccine among mothers with a teenage daughter in Weihai, Shandong, China. A cross-sectional survey was conducted in 2013 with a sample of 1850 mothers who had a daughter (aged 9-17 years) attending primary, junior and senior high schools. In the final sample (N = 1578, response rate 85.30%), awareness of HPV was reported by 305 (19.32%) mothers. Awareness varied significantly by daughter's age (P<0.01), mother's education level (P<0.01), mother's occupation (P<0.01), household income (P<0.01) and residence type (P<0.01). Knowledge about HPV/HPV vaccine was poor with a mean total score of 3.56 (SD = 2.40) out of a possible score of 13. Mothers with a higher education level reported higher levels of knowledge (P = 0.02). Slightly more than one-fourth (26.49%) of mothers expressed their potential acceptability of HPV vaccine for their daughters. Acceptability increased along with increased daughters' age (P<0.01), household income (P<0.01) and knowledge level (P<0.01). House wives and unemployed mothers had the highest acceptability (P<0.01). The most common reasons for not accepting HPV vaccination were "My daughter is too young to have risk of cervical cancer (30.95%)", "The vaccine has not been widely used, and the decision will be made after it is widely used (24.91%)", "Worry about the safety of the vaccine (22.85%)". Awareness and knowledge of HPV/HPV vaccines are poor and HPV vaccine acceptability is low among these Chinese mothers. These results may help inform appropriate health education programs in this population.