Marinobacter shengliensis subsp. alexandrii Subsp. Nov., Isolated from Cultivable Phycosphere Microbiota of Highly Toxic Dinoflagellate Alexandrium catenella LZT09 and Description of Marinobacter shengliensis Subsp. shengliensis Subsp. Nov.

Phycosphere hosts the boundary of unique holobionts harboring dynamic algae-bacteria interactions. During our investigating the microbial consortia composition of phycosphere microbiota (PM) derived from diverse harmful algal blooms (HAB) dinoflagellates, a novel rod-shaped, motile and faint yellow-pigmented bacterium, designated as strain LZ-6 T, was isolated from HAB Alexandrium catenella LZT09 which produces high levels paralytic shellfish poisoning toxins. Phylogenetic analysis based on 16S rRNA gene and two housekeeping genes, rpoA and pheS sequences showed that the novel isolate shared the highest gene similarity with Marinobacter shengliensis CGMCC 1.12758 T (99.6%) with the similarity values of 99.6%, 99.9% and 98.5%, respectively. Further phylogenomic calculations of average nucleotide identity (ANI), average amino acid identity (AAI) and digital DNA-DNA hybridization (dDDH) values between strains LZ-6 T and the type strain of M. shengliensis were 95.9%, 96.4% and 68.5%, respectively. However, combined phenotypic and chemotaxonomic characterizations revealed that the new isolate was obviously different from the type strain of M. shengliensis. The obtained taxonomic evidences supported that strain LZ-6 T represents a novel subspecies of M. shengliensis, for which the name is proposed, Marinobacter shengliensis subsp. alexandrii subsp. nov. with the type strain LZ-6 T (= CCTCC AB 2018388TT = KCTC 72197 T). This proposal automatically creates Marinobacter shengliensis subsp. shengliensis for which the type strain is SL013A34A2T (= LMG 27740 T = CGMCC 1.12758 T).

A distal ileum malignant peripheral nerve sheath tumor causing intussusception in a patient in China: a case report.

BACKGROUND: Malignant peripheral nerve sheath tumors (MPNSTs) arise from a peripheral nerve or display nerve sheath differentiation. Most MPNSTs typically originate on the trunk, extremities, head, neck, and paravertebral regions. Gastrointestinal MPNSTs are rare entities with only 10 cases reported worldwide in the literatures. CASE PRESENTATION: Here, we report the first Chinese case of a malignant peripheral nerve sheath tumor of the distal ileum presenting as intussusception. A 53-year-old female patient without pathological antecedent for neurofibromatosis was admitted with pain in the right lower abdomen and multiple episodes of vomiting for 1 week. Preoperative diagnosis was intussusception with a contrast-enhanced computed tomography scan (CECT) of the abdomen showing characteristic target sign. Due to difficulty reducing the ileum-colon intussusception, right hemicolectomy with ileocolostomy was performed. Histopathology was suggestive of low-grade MPNST. The patient received postoperative care and was followed up for 9 months. There is no sign of tumor recurrence and metastatic disease. CONCLUSIONS: This case is unique in terms of a rare tumor presenting with unusual complication.

Biological characteristics of Chinese precocious strain of eimeria acervulina and its immune efficacy against different field strains.

In this study, the biologic characteristics of one experimental precocious strain of Eimeria acervulina and seven field isolates from different geographic locations in China were compared, and the immune efficacy of two precocious strains against coccidiosis in chickens was assessed to explore their potential use as coccidiosis vaccines. All the different strains were purified by single oocyst separation and their monospecificity was confirmed using E acervulina-specific PCR assays. The average sizes of E. acervulina oocysts were 18.28-20.19 X 14.09-14.79 microm and the shape indexes were from 1.28 to 1.40. The prepatent periods ranged from 93 to 115 hr, except for the Heyuan precocious strain (HYP; 75 hr). Chickens infected with Huadu field strain (GHD) produced the highest oocyst output whereas HYP induced the lowest level. When inoculated with 50,000 sporulated oocysts or more, the average weight gains of infected chickens were reduced, with apparent clinical symptoms. To assess the immunogenicity of precocious strains HYP and Baoding (BDP), birds were orally immunized and challenged with seven different field strains of E. acervulina. Body weight gain, fecal oocyst output, and gut lesion scores were compared to evaluate their vaccine potential. The results showed that the average body weight gains of chickens in all the vaccinated and challenged groups were higher than those of nonvaccinated and challenged groups. In general, oocyst shedding was reduced 34.39%-95.31% and gut lesion scores decreased 31.03%-86.21% compared with unvaccinated and challenged control chickens. In summary, this study indicated that the precocious strains of E. acervulina could induce a protective immune effect with various responses against coccidiosis caused by different field strains.

Seroprevalence of Epizootic Hemorrhagic Disease Virus in Guangdong Cattle Farms during 2013-2017, China.

Epizootic hemorrhagic disease (EHD) is an infectious viral disease caused by epizootic hemorrhagic disease virus (EHDV) and EHDV frequently circulates in wild and domestic ruminants. Sporadic outbreaks of EHD have caused thousands of deaths and stillbirths on cattle farms. However, not much is known about the circulating status of EHDV in Guangdong, southern China. To estimate the seroprevalence of EHDV in Guangdong province, 2886 cattle serum samples were collected from 2013 to 2017 and tested for antibodies against EHDV using a competitive ELISA. The overall seroprevalence of EHDV reached 57.87% and was highest in autumn (75.34%). A subset of positive samples were serotyped by a serum neutralization test, showing that EHDV serotypes 1 and 5-8 were circulating in Guangdong. In addition, EHDV prevalence always peaked in autumn, while eastern Guangdong had the highest EHDV seropositivity over the five-year period, displaying apparent temporal-spatial distribution of EHDV prevalence. A binary logistic model analysis indicated a significant association between cattle with BTV infections and seroprevalence of EHDV (OR = 1.70, p < 0.001). The co-infection of different serotypes of EHDV and BTV raises a high risk of potential genomic reassortment and is likely to pose a significant threat to cattle, thus urging more surveillance to monitor their circulating dynamics in China.

Genomic characterization and phylogenetic analysis of a novel Nairobi sheep disease genogroup Orthonairovirus from ticks, Southeastern China.

The increasing prevalence and transmission of tick-borne diseases, especially those emerging ones, have posed a significant threat to public health. Thus, the discovery of neglected pathogenic agents carried and transmitted by ticks is urgently needed. Using unbiased high-throughput sequencing, a novel Orthonairovirus designated as Meihua Mountain virus (MHMV), was identified in bloodsucking ticks collected from cattle and wild boars in Fujian province, Southeastern China. The full-length genome was determined by RT-PCR and RACE. Genomic architecture of MHMV shares typical features with orthonairoviruses. Phylogenetic analyses suggested that MHMV is clustered into the Nairobi sheep disease (NSD) genogroup of the genus Orthonairovirus and is closely related to the Hazara virus. The RdRp, GPC, and N protein of MHMV shares 62.3%-83.5%, 37.1%-66.1%, and 53.4%-77.3% amino acid identity with other NSD genogroup viruses, respectively, representing a novel species. The overall pooled prevalence of MHMV in ticks was 2.53% (95% CI: 1.62%-3.73%, 22 positives of 134 tick pools), with 7.38% (95% CI: 3.84%-12.59%, 11 positives of 18 pools) in Haemaphysalis hystricis, 6.02% (95% CI: 1.85%-14.22%, four positives of eight pools) in H. formosensis, 25.03% (95% CI: 9.23%-54.59%, six positive of eight pools) in Dermacentor taiwanensis, and 0.16% (95% CI: 0.01%-0.72%, one positive of 100 pools) in Rhipicephalus microplus. This study presented the first report of tick-carried Orthonairovirus in Fujian province and highlighted the broad geographic distribution and high genetic diversity of orthonairoviruses in China.

Ancylostoma ceylanicum Infection in a Miniature Schnauzer Dog Breed.

PURPOSE: Canine hookworm disease is a global zoonotic parasitic disease caused by a variety of nematodes in families Ancylostomatidae, including Ancylostoma spp., Necator spp., and Uncinaria spp., in the small intestine (mainly the duodenum) of dogs. The disease is widely distributed in China. The purpose of this study is to systematically diagnose and treat canine hookworm disease through the case of miniaturization Schnauzer dog feed infected with A. ceylanicum, so as to provide experimental basis for subsequent prevention and control of canine hookworm disease. METHODS: In the current study, we isolated hookworm eggs from a diseased miniature schnauzer, then the polymerase chain reaction (PCR) was used to amplify the ITS1-5.8S-ITS2 gene sequence from genomic DNA extracted from hookworms. Phylogenetic analysis based on ITS1-5.8S-ITS2 gene sequence sequences was inferred using MEGA-X. After phylogenetic analysis, etiologic and symptomatic therapies were used to treat the canine hookworm disease. RESULTS: The sequencing results showed that the length of the ITS1-5.8S-ITS2 gene sequence was approximately 960 bp, and ITS1 and ITS2 were extracted to analyze similarity with other hookworms to build a phylogenetic tree. After phylogenetic analysis, the results showed that the diseased miniature schnauzer was infected by A. ceylanicum. Using etiologic and symptomatic therapies, the sick dog with an A. ceylanicum infection was also treated for 5 days. CONCLUSIONS: To our knowledge, this is the first report of diagnosis and treatment for canine hookworm disease in Guangzhou city. In addition, with the improvement of economic level, the scale of pet dog breeding is also increasing. The diagnostic methods and treatment schemes adopted in this report will help to standardize the prevention and control of canine hookworm disease.

Prevalence and Population Genetics Analysis of Enterocytozoon bieneusi in Dairy Cattle in China.

Enterocytozoon bieneusi, an obligate intracellular pathogen, can infect various hosts. In this study, 3527 dairy cattle fecal specimens were collected from different geographic locations in China (including 673 from Shandong province, 1,440 from Guangdong province and 1,414 from Gansu province) and examined for the presence of E. bieneusi using polymerase chain reactions targeting the ribosomal internal transcribed spacer (ITS). The dominant genotypes identified were further subtyped by multilocus sequence typing. The overall prevalence of E. bieneusi was 14.2% (501/3527), with a significant difference in prevalence among the different geographical locations (P < 0.001). Our logistic regression analysis showed that all four variables (farming model, location, age, and clinical manifestations) had strong effects on the risk of contracting E. bieneusi. Sequence analysis revealed 11 genotypes: eight known genotypes (J, I, BEB4, BEB10, D, EbpC, CM19, and CM21) and three novel genotypes (named here as CGC1, CGC2, and CGC3). Genotypes J and I, the commonest, were found on all farms across the three provinces. Our linkage disequilibrium analysis showed a clonal population structure in the E. bieneusi dairy cattle population but the ITS genotypes had different population structures. Phylogenetic and haplotype network analysis showed the absence of geographical segregation in the E. bieneusi dairy cattle populations. Instead, they revealed the presence of host adaptation to the E. bieneusi populations in various animals. Our findings augment the current understanding of E. bieneusi transmission dynamics.

Characterization of cattle-origin ticks from Southern China.

To characterize ticks in cattle from Guangdong Province and Guangxi Zhuang Nationality Autonomous Region, Southern China, 783 cattle in four localities were examined. Among them, 232 (29.63%) cattle were positive for tick infection. A total of 503 ticks collected in these cattle were further investigated. Two Rhipicephalus species, namely R. microplus and R. sanguineus, were firstly identified by morphological features. Thereinto, R. microplus is the prevalent species in cattle in southern China, with high prevalent in summer and autumn annually. Mixed infection of R. microplus and R. sanguineus was just found in yellow cattle. To further confirm the morphological identification of these cattle-origin ticks, a phylogeographic analysis inferred from the sequences of the ribosomal internal transcribed spacer-2 (ITS-2) was performed, and R. microplus and R. sanguineus were identified. However, the morphological taxonomy of R. microplus has been challenged in recent years. The mitochondrial cytochrome c oxidase subunit 1 (cox1) marker was then used to provide higher resolution of R. mircoplus complex. The re-constructed cox1 phylogenetic tree further identified these R. mircoplus tick samples as R. microplus Clade A. These findings illustrated the prevalence and characterization of cattle-origin ticks in Southern China for the first time, and provided base-line information for further control of tick and tick-borne disease in these areas.

Downregulation of leptin inhibits growth and induces apoptosis of lung cancer cells via the Notch and JAK/STAT3 signaling pathways.

Previous studies have documented that leptin is involved in the pathogenesis of many human cancer types by regulation of numerous signal transduction pathways. The aim of this study was to investigate the biological roles of leptin and the mechanisms attributed to its action in non-small cell lung cancer (NSCLC) cell lines. The expression of leptin was measured by quantitative real-time PCR and western blot in seven NSCLC cell lines. Proliferation and apoptosis of NSCLC cells in response to leptin knockdown were determined by MTT assay and flow cytometry, respectively. The effect of leptin knockdown on the Notch and JAK/STAT3 signaling pathways was further examined by western blot. Leptin expression was significantly increased in NSCLC cell lines compared with normal human bronchial epithelial cell HBE. Leptin knockdown inhibited cell proliferation and induced apoptosis in NSCLC cell lines through inactivation of the Notch and JAK/STAT3 signaling pathways. Furthermore, gene silencing of Notch signaling with Notch-1 siRNA or inhibition of JAK/STAT3 signaling by JSI-124, an inhibitor of STAT3, resulted in proliferation inhibition and apoptosis induction in NSCLC A549 cells. Our findings suggested that leptin knockdown could become a new approach for the prevention of lung cancer progression, which is likely to be mediated at least partially by inactivation of the Notch and JAK/STAT3 signaling pathways.