The Role of Exosomes and Exosomal Noncoding RNAs From Different Cell Sources in Spinal Cord Injury.

Spinal cord injury (SCI) not only affects the quality of life of patients but also poses a heavy burden on their families. Therefore, it is essential to prevent the occurrence of SCI; for unpreventable SCI, it is critical to develop effective treatments. In recent years, various major breakthroughs have been made in cell therapy to protect and regenerate the damaged spinal cord via various mechanisms such as immune regulation, paracrine signaling, extracellular matrix (ECM) modification, and lost cell replacement. Nevertheless, many recent studies have shown that the cell therapy has many disadvantages, such as tumorigenicity, low survival rate, and immune rejection. Because of these disadvantages, the clinical application of cell therapy is limited. In recent years, the role of exosomes in various diseases and their therapeutic potential have attracted much attention. The same is true for exosomal noncoding RNAs (ncRNAs), which do not encode proteins but affect transcriptional and translational processes by targeting specific mRNAs. This review focuses on the mechanism of action of exosomes obtained from different cell sources in the treatment of SCI and the regulatory role and therapeutic potential of exosomal ncRNAs. This review also discusses the future opportunities and challenges, proposing that exosomes and exosomal ncRNAs might be promising tools for the treatment of SCI.

Technical Tips for Percutaneous Transforaminal Endoscopic Discectomy: A Three-step Maneuver for Puncture and Early Clinical Experience.

OBJECTIVE: To investigate the feasibility and efficacy of percutaneous transforaminal endoscopic discectomy (PTED) with three-step maneuver for puncture (TSMP) for lumbar herniated disc (LDH). METHODS: We performed a retrospective review of 30 patients who underwent PTED using TSMP for LDH and met inclusion criteria from January 2018 to September 2018. The primary outcome, leg or back pain, was assessed using Visual Analogue Scale (VAS). Patient surgical satisfaction was measured at 12 months post surgery using a five-point Likert scale. Potential prognostic factors measured were demographic characteristics, duration of symptom (DOS), and involved levels. Statistical analysis was performed using Fisher exact test and t-test. TSMP is a three-step maneuver that builds on the concept of needle puncture site and trajectory determination based on the principles of Kambin's triangle. First, accurate direction of the puncture is confirmed by inserting the needle horizontally. Then by gradually raising the needle tail in the manner described, the superior articular facet and the intervertebral foramen are sequentially located. Finally, the needle tip slides into the intervertebral foramen to reach the target superior articular facet. RESULTS: Preoperative mean VAS was 7.6 ± 1.19, which decreased to 1.4 ± 0.97 at 12 months following treatment (P < 0.0001). Rates of surgical satisfaction per Likert scale were as follows: very satisfied and satisfied in 26 patients (86.7%). Three recurrent disc herniations of adjacent segmental levels were observed in the L5-S1 group at eight and 12 months after surgery. VAS scores at 12 months varied significantly between L4-L5 level surgery and L5-S1 level surgery groups (P < 0.01). CONCLUSION: TSMP is a reliable technique for puncture into the intervertebral foramen.

Population genetic analysis of the Plasmodium falciparum erythrocyte binding antigen-175 (EBA-175) gene in Equatorial Guinea.

BACKGROUND: Plasmodium falciparum erythrocyte binding antigen-175 (PfEBA-175) is a candidate antigen for a blood-stage malaria vaccine, while various polymorphisms and dimorphism have prevented to development of effective vaccines based on this gene. This study aimed to investigate the dimorphism of PfEBA-175 on both the Bioko Island and continent of Equatorial Guinea, as well as the genetic polymorphism and natural selection of global PfEBA-175. METHODS: The allelic dimorphism of PfEBA-175 region II of 297 bloods samples from Equatorial Guinea in 2018 and 2019 were investigated by nested polymerase chain reaction and sequencing. Polymorphic characteristics and the effect of natural selection were analyzed using MEGA 7.0, DnaSP 6.0 and PopART programs. Protein function prediction of new amino acid mutation sites was performed using PolyPhen-2 and Foldx program. RESULTS: Both Bioko Island and Bata district populations, the frequency of the F-fragment was higher than that of the C-fragment of PfEBA-175 gene. The PfEBA-175 of Bioko Island and Bata district isolates showed a high degree of genetic variability and heterogeneity, with π values of 0.00407 & 0.00411 and Hd values of 0.958 & 0.976 for nucleotide diversity, respectively. The values of Tajima's D of PfEBA-175 on Bata district and Bioko Island were 0.56395 and - 0.27018, respectively. Globally, PfEBA-175 isolates from Asia were more diverse than those from Africa and South America, and genetic differentiation quantified by the fixation index between Asian and South American countries populations was significant (FST > 0.15, P < 0.05). A total of 310 global isolates clustered in 92 haplotypes, and only one cluster contained isolates from three continents. The mutations A34T, K109E, D278Y, K301N, L305V and D329N were predicted as probably damaging. CONCLUSIONS: This study demonstrated that the dimorphism of F-fragment PfEBA-175 was remarkably predominant in the study area. The distribution patterns and genetic diversity of PfEBA-175 in Equatorial Guinea isolates were similar another region isolates. And the levels of recombination events suggested that natural selection and intragenic recombination might be the main drivers of genetic diversity in global PfEBA-175. These results have important reference value for the development of blood-stage malaria vaccine based on this antigen.

Genetic diversity and natural selection on the thrombospondin-related adhesive protein (TRAP) gene of Plasmodium falciparum on Bioko Island, Equatorial Guinea and global comparative analysis.

BACKGROUND: Thrombospondin-related adhesive protein (TRAP) is a transmembrane protein that plays a crucial role during the invasion of Plasmodium falciparum into liver cells. As a potential malaria vaccine candidate, the genetic diversity and natural selection of PfTRAP was assessed and the global PfTRAP polymorphism pattern was described. METHODS: 153 blood spot samples from Bioko malaria patients were collected during 2016-2018 and the target TRAP gene was amplified. Together with the sequences from database, nucleotide diversity and natural selection analysis, and the structural prediction were preformed using bioinformatical tools. RESULTS: A total of 119 Bioko PfTRAP sequences were amplified successfully. On Bioko Island, PfTRAP shows its high degree of genetic diversity and heterogeneity, with π value for 0.01046 and Hd for 0.99. The value of dN-dS (6.2231, p < 0.05) hinted at natural selection of PfTRAP on Bioko Island. Globally, the African PfTRAPs showed more diverse than the Asian ones, and significant genetic differentiation was discovered by the fixation index between African and Asian countries (Fst > 0.15, p < 0.05). 667 Asian isolates clustered in 136 haplotypes and 739 African isolates clustered in 528 haplotypes by network analysis. The mutations I116T, L221I, Y128F, G228V and P299S were predicted as probably damaging by PolyPhen online service, while mutations L49V, R285G, R285S, P299S and K421N would lead to a significant increase of free energy difference (ΔΔG > 1) indicated a destabilization of protein structure. CONCLUSIONS: Evidences in the present investigation supported that PfTRAP gene from Bioko Island and other malaria endemic countries is highly polymorphic (especially at T cell epitopes), which provided the genetic information background for developing an PfTRAP-based universal effective vaccine. Moreover, some mutations have been shown to be detrimental to the protein structure or function and deserve further study and continuous monitoring.

Genetic polymorphism of Plasmodium falciparum circumsporozoite protein on Bioko Island, Equatorial Guinea and global comparative analysis.

BACKGROUND: Plasmodium falciparum circumsporozoite protein (PfCSP) is a potential malaria vaccine candidate, but various polymorphisms of the pfcsp gene among global P. falciparum population become the major barrier to the effectiveness of vaccines. This study aimed to investigate the genetic polymorphisms and natural selection of pfcsp in Bioko and the comparison among global P. falciparum population. METHODS: From January 2011 to December 2018, 148 blood samples were collected from P. falciparum infected Bioko patients and 96 monoclonal sequences of them were successfully acquired and analysed with 2200 global pfcsp sequences mined from MalariaGEN Pf3k Database and NCBI. RESULTS: In Bioko, the N-terminus of pfcsp showed limited genetic variations and the numbers of repetitive sequences (NANP/NVDP) were mainly found as 40 (35%) and 41 (34%) in central region. Most polymorphic characters were found in Th2R/Th3R region, where natural selection (p > 0.05) and recombination occurred. The overall pattern of Bioko pfcsp gene had no obvious deviation from African mainland pfcsp (Fst = 0.00878, p < 0.05). The comparative analysis of Bioko and global pfcsp displayed the various mutation patterns and obvious geographic differentiation among populations from four continents (p < 0.05). The global pfcsp C-terminal sequences were clustered into 138 different haplotypes (H_1 to H_138). Only 3.35% of sequences matched 3D7 strain haplotype (H_1). CONCLUSIONS: The genetic polymorphism phenomena of pfcsp were found universal in Bioko and global isolates and the majority mutations located at T cell epitopes. Global genetic polymorphism and geographical characteristics were recommended to be considered for future improvement of malaria vaccine design.

[Mechanism of Soil Eco-Functional Stability Under Pyrene/Cadmium Simplex and Combined Pollution Stress].

In current scenario,the soil pollution has become very severe and its effects on agricultural and ecological security issues cannot be ignored as various contaminants are discharged into soil.Thus,the soil pollution is exigent and has to be solved.This research took soil resistance (Rt),resilience (Rl) and stability (Sb) as evaluation indexes for judging soil quality by exerting different concentration (concentration ratio) gradient of pyrene (PYR),cadmium (Cd) and pyrene/cadmium (PYR/Cd) combined pollutants.A sympathetic description was showed from the aspects of microbial activity,diversity and abundance of soil ecosystem,and the models were constructed to describe the dose-response relationship between PYR-Sb and Cd-Rt.The research showed that different types of pollutants had certain inhibition on soil DOC content.In Cd and PYR simplex pollution,soil microbial mean biomass and colony number decreased with increasing concentration of pollutants.In PYR/Cd combined pollution,the ratio of PYR and Cd had a negative correlation with the decreasing rate of DOC and resistance,meanwhile Cd had a prominent influence on the above-mentioned correlations,in other words,the soil with higher concentration of Cd had lower DOC decrease rate and resistance,and Cd would have dominant inhibition effect on microorganisms under PYR/Cd combined pollution.In addition,this study found the significant correlation of cPYR-Sb and cCd-Rt,and built the binomial forecasting model to describe the dose-response relationship of cPYR-Sb and cCd-Rt.

Paenibacillus herberti sp. nov., an endophyte isolated from Herbertus sendtneri.

Strain R33(T), an endophyte recovered from Herbertus sendtneri, was identified as representing a novel species of the genus Paenibacillus by using a polyphasic taxonomic approach. The novel strain was observed to be a Gram-stain positive, aerobic, rod-shaped, motile and endospore-forming bacterium. The major polar lipids of strain R33(T) were identified as diphosphatidylglycerol, phosphatidylethanolamine, along with lesser amounts of phosphatidylglycerol, three unidentified aminophospholipids, two unidentified phospholipids and two unidentified lipids. The predominant isoprenoid quinone was identified as MK-7. The major fatty acids (>8.0 %) were found to be anteiso-C15:0 (40.0 %), C16:1 ω11c (9.4 %), C16:1 ω7c alcohol (8.5 %) and C16:0 (8.2 %). The diamino acid found in the cell-wall peptidoglycan was meso-diaminopimelic acid. The G+C content of genomic DNA was determined to be 56.9 mol%. The 16S rRNA gene sequence similarities of strain R33(T) to other Paenibacillus species ranged from 91.6 to 97.2 %, with high similarities to Paenibacillus humicus PC-147(T) and Paenibacillus pasadenensis SAFN-007(T). The phylogenetic analyses based on 16S rRNA gene sequences and the partial rpoB gene confirmed that strain R33(T) belongs to the genus Paenibacillus. However, strain R33(T) shows differential molecular characteristics compared to other related Paenibacillus species based on 16S rDNA-RFLP analyses; the DNA-DNA relatedness values between strain R33(T) and P. humicus PC-147(T), and that between strain R33(T) and P. pasadenensis SAFN-007(T), were 35.0 ± 2.0 and 41.4 ± 0.9 %, respectively. Based on its phenotypic, chemotaxonomic and phylogenetic properties, strain R33(T) is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus herberti is proposed (type strain R33(T) = CGMCC 1.15042(T) = DSM 29849(T)).

Chryseobacterium takakiae sp. nov., a member of the phylum Bacteroidetes isolated from Takakia lepidozioides.

A Gram-stain-negative, rod-shaped and non-endospore-forming bacterium, designated strain AG1-2(T), was isolated from Takakia lepidozioides collected from the Gawalong glacier in Tibet, China and characterized using a polyphasic taxonomic approach. The predominant fatty acids of strain AG1-2(T) were iso-C15 : 0 (36.0 %), iso-C17:0 3-OH (20.2 %), summed feature 9 (iso-C17:1ω9c and/or C16:0 10-methyl, 16.4%) and summed feature 3 (C16:1ω7c and/or C16:1ω6c, 11.1%). The major polar lipids were phosphatidylethanolamine, three unidentified aminolipids and two unidentified lipids. Strain AG1-2(T) contained MK-6 as the dominant menaquinone, and the genomic DNA G+C content was 37.3 mol%. The phylogenetic analysis based on the 16S rRNA gene sequences showed that strain AG1-2(T) was affiliated to species of the genus Chryseobacterium, and its closest related species were Chryseobacterium taiwanense Soil-3-27(T), Chryseobacterium hispalense AG13(T), Chryseobacterium camelliae THG C4-1(T) and Chryseobacterium taeanense PHA3-4(T) with a sequence similarity of 98.0, 97.8, 97.3 and 97.1%, respectively. However, the DNA-DNA relatedness values between these strains and strain AG1-2(T) were 29, 21, 21 and 45%, respectively. Based on phylogenetic inference and phenotypic data, strain AG1-2(T) is considered to represent a novel species of the genus Chryseobacterium, for which the name Chryseobacterium takakiae sp. nov. is proposed. The type strain is AG1-2(T) ( = CGMCC 1.12488(T) = DSM 26898(T)).

Chryseobacterium polytrichastri sp. nov., isolated from a moss (Polytrichastrum formosum), and emended description of the genus Chryseobacterium.

A Gram-stain negative, rod-shaped and non-endospore forming bacterium, designated strain YG4-6(T), was isolated from Polytrichastrum formosum collected from Gawalong glacier in Tibet, China and characterized by using a polyphasic taxonomic approach. The predominant fatty acids of strain YG4-6(T) were identified as iso-C15:0 (29.3 %), summed feature 3 (C16:1 ω7c and/or C16:1 ω6c as defined by MIDI, 23.5 %) and iso-C17:0 3-OH (16.5 %). The major polar lipids were found to consist of five unidentified aminolipids and three unidentified lipids. Strain YG4-6(T) was found to contain MK-6 as the dominant menaquinone and the G+C content of its genomic DNA was determined to be 37.3 mol%. The phylogenetic analysis based on 16S rRNA gene sequences showed that strain YG4-6(T) is affiliated to Chryseobacterium species, and its closest related species were Chryseobacterium aahli T68(T) (97.9 % sequence similarity), Chryseobacterium zeae JM-1085(T) (97.8 % sequence similarity), Chryseobacterium yeoncheonense DCY67(T) (97.6 % sequence similarity) and Chryseobacterium soldanellicola NBRC 100864(T) (97.2 % sequence similarity). However, the DNA-DNA relatedness values between these strains and strain YG4-6(T) were found to be clearly below 70 %. Based on the phylogenetic inference and phenotypic data, strain YG4-6(T) is considered to represent a novel species of the genus Chryseobacterium, for which the name Chryseobacterium polytrichastri sp. nov. is proposed. The type strain is YG4-6(T) (=CGMCC 1.12491(T) = DSM 26899(T)). An emended description of the genus Chryseobacterium is also proposed.

Mucilaginibacter polytrichastri sp. nov., isolated from a moss (Polytrichastrum formosum), and emended description of the genus Mucilaginibacter.

A Gram-staining-negative, rod-shaped, non-spore-forming bacterium, designated strain RG4-7(T), was isolated from the moss Polytrichastrum formosum collected from Gawalong glacier in Tibet, China, and characterized by using a polyphasic taxonomic approach. The predominant fatty acids of strain RG4-7(T) were summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), iso-C15 : 0 and iso-C17 : 0 3-OH. The major polar lipids were phosphatidylethanolamine, one unidentified aminophospholipid, one unidentified phospholipid, two unidentified aminolipids and one unidentified lipid. Strain RG4-7(T) contained MK-7 as the dominant menaquinone and the G+C content of its genomic DNA was 39.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain RG4-7(T) was affiliated to species of the genus Mucilaginibacter, and its closest relative was Mucilaginibacter jinjuensis YC7004(T) (97.0 % sequence similarity). However, the DNA-DNA relatedness between this strain and strain RG4-7(T) was only 49.1±3.7 %. Based on phylogenetic inference and phenotypic data, strain RG4-7(T) is considered to represent a novel species of the genus Mucilaginibacter, for which the name Mucilaginibacter polytrichastri sp. nov. is proposed. The type strain is RG4-7(T) ( = CGMCC 1.12493(T) = DSM 26907(T)). An emended description of the genus Mucilaginibacter is also proposed.

Cnuella takakiae gen. nov., sp. nov., a member of the phylum Bacteroidetes isolated from Takakia lepidozioides.

A Gram-staining-negative, rod-shaped and non-spore-forming bacterium, designated strain RG1-1(T), was isolated from Takakia lepidozioides collected from Gawalong glacier in Tibet, China, and characterized by using a polyphasic taxonomic approach. The predominant fatty acids of strain RG1-1(T) were iso-C(15 : 0) (19.8%), summed feature 3 (C(16 : 1)ω7c and/or C(16 : 1)ω6c, 17.0%), C(16 : 0 (9.9)%) and iso-C(17 : 0) 3-OH (9.4%); its major polar lipids were phosphatidylethanolamine, four unidentified aminolipids, one unidentified phospholipid, one unidentified aminoglycolipid, one unidentified glycolipid, and three unidentified lipids. Strain RG1-1(T) contained MK-7 as the dominant menaquinone, and the G+C content of its genomic DNA was 49.1 mol%. Strain RG1-1(T) exhibited the highest 16S rRNA gene sequence similarity (91.8%) with Flavisolibacter ginsengiterrae Gsoil 492(T) and Flavisolibacter ginsengisoli Gsoil 643(T). Phylogenetic analysis showed that strain RG1-1(T) was a member of the family Chitinophagaceae, phylum Bacteroidetes. On the basis of 16S rRNA gene sequence analysis, and phenotypic and chemotaxonomic data, strain RG1-1(T) is considered to represent a novel species of a novel genus, for which the name Cnuella takakiae gen. nov., sp. nov. is proposed. The type strain is RG1-1(T) ( = CGMCC 1.12492(T) = DSM 26897(T)).