MicroRNA-545-5p regulates apoptosis, migration and invasion of osteosarcoma by targeting dimethyladenosine transferase 1.

The metastasis of osteosarcoma is a major threat to both adolescents and young adults. Identifying novel targets that may prevent osteosarcoma metastasis is critical in developing advanced clinical therapies for treating this cancer. The present study aimed to explore the mechanism of microRNA (miR)-545-5p in the metastasis of osteosarcoma. The present study identified miR-545-5p as a potential target that was downregulated in both osteosarcoma clinical samples and cell lines, and in the latter, ectopically expressed miR-545-5p caused apoptosis. In addition, miR-545-5p exerted inhibitory effects in osteosarcoma migration and invasion. Overexpression of miR-545-5p induced xenograft growth inhibition in vivo. In addition, miR-545-5p targeted dimethyladenosine transferase 1 (DIMT1), an oncogenic protein that facilitates osteosarcoma proliferation, migration and invasion. Taken together, the results of the present study suggest that miR-545-5p functions as a tumor suppressor in osteosarcoma that promotes apoptosis, while inhibiting migration and invasion by targeting DIMT1. Taken together, the results of the present study suggest two potential novel targets for osteosarcoma treatment and metastasis prevention.

Description of Novosphingopyxis iocasae sp. nov., isolated from deep sea sediment from the Mariana Trench, and emended description of the genus Novosphingopyxis.

In this study, we reported a Gram-stain-negative, orange-coloured, rod-shaped, motile and faculatively anaerobic bacterium named strain PB63T, which was isolated from the deep-sea sediment from the Mariana Trench. Growth of PB63T occurred at 10-35 °C (optimum, 28 °C), pH 5.0-8.0 (optimum, 5.0-6.0) and with 0-7 % (w/v) NaCl (optimum, 2-3 %). The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that PB63T represented a member of the genus Novosphingopyxis and was closely related to Novosphingopyxis baekryungensis DSM 16222T (97.9 % sequence similarity). PB63T showed tolerance to a variety of heavy metals, including Co2+, Zn2+, Mn2+ and Cu2+. The complete genome of PB63T was obtained, and many genes involved in heavy metal resistance were found. The genomic DNA G+C content of PB63T was 62.8 mol%. The predominant respiratory quinone of PB63T was ubiquinone-10 (Q-10). The polar lipids of PB63T contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, sphingoglycolipid, glycolipid, phosphatidylcholines and three unidentified lipids. The major fatty acids of PB63T included summed feature 8 (C18 : 1ω7c or/and C18 : 1ω6c), C14 : 0 2-OH, 11-methyl C18 : 1ω7c, C16 : 0, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C17 : 1ω6c. The results of phylogenetic, physiological, biochemical and morphological analyses indicated that strain PB63T represents a novel species of the genus Novosphingopyxis, and the name Novosphingopyxis iocasae sp. nov. is proposed with the type species PB63T (=CCTCC AB 2019195T=JCM 34178T).

Bacillus fonticola sp. nov., isolated from deep sea cold seep sediment.

In this study, we report a novel Gram-positive bacterium, designated as strain CS13T, isolated from deep-sea sediment collected in the cold seep area of the South China Sea. Growth of strain CS13T occurred at 16-37 °C (optimum 25-28 °C), pH 7.0-9.0 (optimum, 7.0), and 0-8% (w/v) NaCl (optimum, 2-3%). Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain CS13T belonged to the genus Bacillus. The closest phylogenetic neighbors of strain CS13T are Bacillus carboniphilus JCM 9731T (96.0%), Bacillus pakistanensis NCCP-168T (95.7%) and Bacillus acidicola 105-2T (95.6%). The genomic DNA G + C content of strain CS13T is 43.7 mol%. The principal respiratory quinone was menaquinone 7 (MK-7). The polar lipids of CS13T contained diphosphatidylglycerol, phosphatidylglycerol, phospholipid, and glycolipid. The major fatty acids of CS13T contained anteiso-C15:0, anteiso-C17:0, C16:0 and C18:0. Strain CS13T harboured meso-diaminopimelic acid as the diagnostic diamino acid. Phylogenetic, physiological, biochemical, and morphological analyses suggested that strain CS13T represents a novel species of genus Bacillus, and the name Bacillus fonticola sp. nov. is proposed for the type species CS13T (= CCTCC AB 2019194T = JCM 33663T).

Outbreak of COVID-19 in a family, Wenzhou, China.

Since December 2019, China has experienced a widespread outbreak of COVID-19. However, at the early stage of outbreak, investigations revealed a variety of patterns resulting in the transmission of COVID-19. Thus, it is essential to understand the transmission types and the potential for sustained human-to-human transmission. Moreover, the information regarding the characteristics of transmission helps in coordinating the current screening programme, and controlling and containing measures, and also, helps in deciding the appropriate quarantine duration. Thus, this investigation reports an outbreak of COVID-19 in a family residing in Wenzhou, Zhejiang, China during the month of January-February 2020.

Global discovery of small RNAs in the fish pathogen Edwardsiella piscicida: key regulator of adversity and pathogenicity.

Recently, bacterial small RNA (sRNA) has been shown to be involved as a key regulator in stress responses. sRNAs of Edwardsiella piscicida, an important aquatic pathogen, are not well characterized to date. In this study, using RNA-seq technology, we globally found and identified sRNA candidates expressed from E. piscicida grown in normal LB medium, acid pressure, iron deficiency stress, and oxidation pressure. A total of 148 sRNAs were found, including 19 previously annotated sRNAs and 129 novel sRNA candidates by searching against the Rfam database. Compared in normal condition, the expression of 103 sRNAs (DEsRNA, differentially expressed sRNA) and 1615 mRNAs (DEmRNAs, differentially expressed mRNA) showed significant differences in three stress sample. Based on the prediction by IntaRNA and relational analysis between DEsRNAs and DEmRNAs, 103 DEsRNAs were predicted to regulate 769 target mRNAs. Pleiotropic function of target DEmRNAs indicated that sRNAs extensively participated in a variety of physiological processes, including response to adversity and pathogenicity, the latter was further confirmed by infection experiment. A large number transcription factors appeared in target genes of sRNAs, which suggested that sRNAs likely deeply interlaced within complex gene regulatory networks of E. piscicida. Moreover, 49 Hfq-associated sRNAs were also identified in this study. In summary, we globally discovered sRNAs for the first time in pathogenic bacteria of fish, and our findings indicated that sRNAs in E. piscicida have important roles in adaptation to environmental stress and pathogenicity. These results also provide clues for deciphering regulation mechanism of gene expression related to physiological response and pathogenicity.

The serine protease autotransporter Tsh contributes to the virulence of Edwardsiella tarda.

The temperature-sensitive hemagglutinin (Tsh), identified as serine protease autotransporters of the Enterobacteriaceae (SPATEs) proteins, is an important virulence factor for avian-pathogenic Escherichia coli (APEC) and uropathogenic E. coli. However, little is known about the role of Tsh as a virulence factor in Edwardsiella tarda, a severe fish pathogen. In this study, we characterized the Tsh of E. tarda (named TshEt) and examined its function and vaccine potential. TshEt is composed of 1224 residues and has three functional domains typical for autotransporters. Quantitative real-time reverse transcriptase-PCR analysis showed that expression of tshEt was upregulated under conditions of high temperature, increased cell density, high pH, and iron starvation and during the infection of host cells. A markerless tsh in-frame mutant strain, TX01Δtsh, was constructed to determine whether TshEt participates in the pathogenicity of E. tarda, Compared to the wild type TX01, TX01Δtsh exhibited (i) retarded biofilm growth, (ii) decreased resistance against serum killing, (iii) impaired ability to block the host immune response, (iv) attenuated tissue and cellular infectivity. Introduction of a trans-expressed tsh gene restored the lost virulence of TX01Δtsh. The passenger domain of TshEt contains a putative serine protease (PepS) that exhibits apparent proteolytic activity when expressed in and purified from E. coli as a recombinant protein (rPepS). When used as a subunit vaccine to immunize Japanese flounder, rPepS was able to induce effective immune protection. This is the first study of Tsh in a fish pathogen, and the results suggest that TshEt exerts pleiotropic effects on the pathogenesis of E. tarda.

Surgical treatment of scoliosis associated with syringomyelia with no or minor neurologic symptom.

PURPOSE: Syringomyelia with coexisting intraspinal abnormities is thought to increase the risk of neurologic injury during surgical correction of the scoliosis. However, surgical treatment for intraspinal abnormities carries significant morbidity risks including worsening neurological function and wound complications. The authors' aim in this study was to evaluate one-stage posterior correction of scoliosis in this patient population without prophylactic surgical treatment for neural axis malformations before scoliosis correction. METHODS: A total of 29 patients with syringomyelia and coexisting intraspinal abnormities who underwent scoliosis correction were evaluated. The average age was 15.6 years (range 12-23). All patients were examined for neural axis abnormalities using MRI, including syringomyelia with Chiari I malformation in 18 patients, syringomyelia with tethered cord and/or diastematomyelia in 11. None of patients presented with symptoms suggesting significant neurological dysfunction. The surgical efficacies and complications of correction were reviewed. RESULTS: The preoperative Cobb angle of major coronal curve averaged 65° (range 46°-95°), and it measured 28° (range 22°-43°) at the last follow-up, for a 63 % correction. Maximal kyphosis averaged 52° (range 41°-69°) preoperatively, and improved to 29° (range 22°-43°) at ultimate follow-up, for a 46 % correction. The average follow-up was 6 years (4-8 years). None of the patients experienced deterioration in their neurologic status. CONCLUSION: The study results suggested that prophylactic neurosurgery for intraspinal abnormality may be unnecessary in patients with asymptomatic or minor symptomatic syringomyelia and coexisting intraspinal abnormities. One-stage posterior correction of scoliosis in this patient population does not involve significant complications and seems to be an alternative and safe treatment option.

Clinical analysis of 73 cases of intraspinal nerve sheath tumor.

Seventy-three patients with spinal nerve sheath tumor who were surgically treated in our hospital during the years 2004-2010 were retrospectively reviewed with respect to recovery of neurological function, recurrence of the tumor and occurrence of kyphotic deformities. Preoperative clinical manifestations, imaging data, surgical records and follow-up results were comprehensively analyzed. The follow-up duration was 12-60 months with an average of 32.0 months. Out of the 73 cases enrolled, 69 had gradual recovery of sensation, motor and sphincter functions 1 week to 3 months after operation. Forty-six cases had incomplete paralysis, whose American Spinal Injury Association (ASIA) grades, however, were gradually increased during the follow-up period, 4 cases had no significant improvement of the clinical symptoms and no change in ASIA grades during the follow-up period. Two cases had postoperative recurrence of the tumor. There were no deaths, no spinal instability, and no kyphotic malformations found in any cases. Our study indicated that complete removal of the tumor is important for good recovery, and an ideal surgical method may reduce the recurrence of the tumor or the occurrence of complications.