Mesonia profundi sp. nov., isolated from deep-sea sediment of the Mariana Trench.

A Gram-stain-negative, aerobic, rod-shaped, non-flagellated, non-gliding bacterial strain, designated MT50T, was isolated from a deep-sea sediment sample collected from the Mariana Trench. Optimal growth of strain MT50T was observed at 25 °C, pH 7.0-7.5 and in the presence of 3-5 % (w/v) NaCl. The strain was positive for oxidase and catalase. Phylogenetic analysis of 16S rRNA gene sequences revealed that strain MT50T is affiliated with the genus Mesonia, showing the highest sequence similarity (98.5 %) to the type strain of Mesonia ostreae. The digital DNA-DNA hybridization and average nucleotide identity values between strain MT50T and four closely related type strains of known Mesonia species (14.1-54.8 % and 72.7-86.8 %, respectively) were all below the threshold values to discriminate bacterial species, indicating that strain MT50T is affiliated with a novel species within the genus. The genomic G+C content deduced from the genome of strain MT50T was 36.2 mol%. The major fatty acids of strain MT50T were iso-C15 : 0, iso-C17 : 0 3-OH and anteiso-C15 : 0. The predominant respiratory quinone of the strain was MK-6. The polar lipids of strain MT50T included phosphatidylethanolamine and two unidentified lipids. Based on the polyphasic data presented in this study, strain MT50T represents a novel species of the genus Mesonia, for which the name Mesonia profundi sp. nov. is proposed. The type strain is MT50T (=MCCC 1K07833T=KCTC 92380T).

Anaerobic thiosulfate oxidation by the Roseobacter group is prevalent in marine biofilms.

Thiosulfate oxidation by microbes has a major impact on global sulfur cycling. Here, we provide evidence that bacteria within various Roseobacter lineages are important for thiosulfate oxidation in marine biofilms. We isolate and sequence the genomes of 54 biofilm-associated Roseobacter strains, finding conserved sox gene clusters for thiosulfate oxidation and plasmids, pointing to a niche-specific lifestyle. Analysis of global ocean metagenomic data suggests that Roseobacter strains are abundant in biofilms and mats on various substrates, including stones, artificial surfaces, plant roots, and hydrothermal vent chimneys. Metatranscriptomic analysis indicates that the majority of active sox genes in biofilms belong to Roseobacter strains. Furthermore, we show that Roseobacter strains can grow and oxidize thiosulfate to sulfate under both aerobic and anaerobic conditions. Transcriptomic and membrane proteomic analyses of biofilms formed by a representative strain indicate that thiosulfate induces sox gene expression and alterations in cell membrane protein composition, and promotes biofilm formation and anaerobic respiration. We propose that bacteria of the Roseobacter group are major thiosulfate-oxidizers in marine biofilms, where anaerobic thiosulfate metabolism is preferred.

Salinimicrobium profundisediminis sp. nov., isolated from deep-sea sediment of the Mariana Trench.

A Gram-stain-negative, aerobic, rod-shaped, non-gliding bacterial strain, designated as MT39T, was isolated from a deep-sea sediment sample collected from the Mariana Trench. Strain MT39T grew optimally at 35°C and pH 7.0, and could tolerate up to 10% (w/v) NaCl. The strain was positive for catalase and negative for oxidase. The genome of strain MT39T was 4 033 307 bp, with a 41.1 mol % genomic G+C content and 3514 coding sequences. Phylogenetic analysis based on 16S rRNA gene sequences placed strain MT39T within the genus Salinimicrobium, showing the highest 16S rRNA gene sequence similarity to Salinimicrobium terrea CGMCC 1.6308T (98.1%). The average nucleotide identity and in silico DNA-DNA hybridization values between strain MT39T and the type strains of seven Salinimicrobium species were all less than the threshold values to discriminate bacterial species, indicating that strain MT39T is affiliated with a novel species within the genus. The major cellular fatty acids of strain MT39T were iso-C15 : 0, anteiso-C15 : 0 and iso-C17 : 0 3-OH. Polar lipids of strain MT39T included phosphatidylethanolamine, one unidentified aminolipid and four unidentified lipids. Menaquinone-6 was the only respiratory quinone in strain MT39T. On the basis of the polyphasic data present in this study, strain MT39T represents a novel species of the genus Salinimicrobium, for which the name Salinimicrobium profundisediminis sp. nov. is proposed, with type strain being MT39T (=MCCC 1K07832T=KCTC 92381T).

Early stage of biofilm assembly on microplastics is structured by substrate size and bacterial motility.

The taxonomic structure of biofilms on 0.3-mm microplastics differed significantly from that on 3-mm microplastics or glass particles. Compared with the 3-mm microplastics, biofilms on 0.3-mm microplastics were enriched for genes involved in flagellar-based motility and chemotaxis, pointing to a more 'mobile' community. The association between motility and bacterial colonization of 0.3-mm microplastics was observed through laboratory experiments using isolated strains.

An electrochemical biosensor for the detection of aflatoxin B1 based on the specific aptamer and HCR biological magnification.

Aflatoxin B1 (AFB1) is a highly toxic mycotoxin, which causes severe acute or cumulative poisoning. Therefore, it is important to develop sensitive and selective detection methods for AFB1 for the safety of food and medicinal herbs. Herein, we have developed a "signal-on" electrochemical aptasensor based on the high specificity of the aptamer and hybridization chain reaction (HCR) biological amplification for AFB1 detection. In this work, thiol-modified complementary DNA (cDNA) immobilized on the surface of a gold electrode (GE) served as an initiator DNA. When AFB1 was present, it competed with the cDNA for binding to the aptamers, which resulted in the detaching of aptamers from the cDNA-aptamer duplexes. Then, the single-stranded cDNA acted as an initiator to trigger the HCR signal amplification. Therefore, long double-stranded DNA (dsDNA) products were produced, which could load large amounts of methylene blue (MB) molecules to generate a distinct electrochemical signal. Under the optimized conditions, the proposed electrochemical aptasensor achieved the ultrasensitive detection of AFB1 with a linear detection range of 0.01-100 pg mL-1, and a limit of detection (LOD) down to 2.84 fg mL-1. Furthermore, the electrochemical aptasensor was successfully applied for detecting AFB1 in corn and two kinds of traditional Chinese medicine samples, indicating the potential value for AFB1 detection in practical samples.

Protective Mechanism of Electroacupuncture on Peripheral Neurotoxicity Induced by Oxaliplatin in Rats.

OBJECTIVE: To study the effect of electroacupuncture (EA) on oxaliplatin-induced peripheral neuropathy (OIPN) in rats. METHODS: Male Sprague-Dawley rats were equally divided into 3 groups using a random number table: the control group, the OIPN group, and the EA (OIPN + EA) group, with 10 rats in each. The time courses of mechanical, cold sensitivity, and microcirculation blood flow intensity were determined. The morphology of the dorsal root ganglion (DRG) was observed by electron microscopic examination. The protein levels of nuclear factor E2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and the transient receptor potential (TRP) protein family in DRGs were assayed by Western blot. RESULTS: EA treatment significantly reduced mechanical allodynia and cold allodynia in OIPN rats (P<0.01). Notably, oxaliplatin treatment resulted in impaired microcirculatory blood flow and pathomorphological defects in DRGs (P<0.01). EA treatment increased the microcirculation blood flow and attenuated the pathological changes induced by oxaliplatin (P<0.01). In addition, the expression levels of Nrf2 and HO-1 were down-regulated, and the TRP protein family was over-expressed in the DRGs of OIPN rats (P<0.01). EA increased the expression levels of Nrf2 and HO-1 and decreased the level of TRP protein family in DRG (P<0.05 or P<0.01). CONCLUSION: EA may be a potential alternative therapy for OIPN, and its mechanism may be mainly mediated by restoring the Nrf2/HO-1 signaling pathway.

Visual detection of aflatoxin B1 based on specific aptamer recognition combining with triple amplification strategy.

A highly sensitive and specific visual detection method for aflatoxin B1 (AFB1) based on the target specificity of aptamer, rolling circle amplification (RCA) and enzyme catalysis biological amplification effect has been established. In this work, AFB1 aptamer immobilized on the surface of magnetic beads (MB) serves as a molecular recognition probe. In the absence of AFB1, the aptamer and auxiliary linking probe (LP) maintain a double stranded state due to partial base pair complementarities. By contrast, in the presence of AFB1, the aptamer preferentially binds to AFB1 specifically, and the LP later restores to a single stranded state. Subsequently, the RCA reaction is triggered by above-mentioned single stranded LP to generate long DNA strands, which are employed to capture amounts of signal probes (SP) and horse radish peroxidases (HRP). Finally, amounts of HRP catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) by H2O2 and leads to a dramatic color change of the solution from colorlessness to deep blue as a signal indicator, obtaining a high sensitivity, high specificity and visual detection of AFB1. Under optimal conditions, a good linear detection range (0.5-40 pg·mL-1) was achieved, and the limit of detection (LOD) was 0.13 pg·mL-1. Besides, the proposed aptasensor showed excellent specificity for AFB1 compared with five other mycotoxins. More than that, all reactions occur on the surface of the magnetic beads, which not only facilitates the detection operation process including the efficient isolation and collection of AFB1 from sample matrix, but also gets better selectivity and stronger resistibility to target analyte in complex sample matrix, adequately indicating its potential application in AFB1 practical detection.

Scientific and technological progress in the microbial exploration of the hadal zone.

The hadal zone is the deepest point in the ocean with a depth that exceeds 6000 m. Exploration of the biological communities in hadal zone began in the 1950s (the first wave of hadal exploration) and substantial advances have been made since the turn of the twenty-first century (the second wave of hadal exploration), resulting in a focus on the hadal sphere as a research hotspot because of its unique physical and chemical conditions. A variety of prokaryotes are found in the hadal zone. The mechanisms used by these prokaryotes to manage the high hydrostatic pressures and acquire energy from the environment are of substantial interest. Moreover, the symbioses between microbes and hadal animals have barely been studied. In addition, equipment has been developed that can now mimic hadal environments in the laboratory and allow cultivation of microbes under simulated in situ pressure. This review provides a brief summary of recent progress in the mechanisms by which microbes adapt to high hydrostatic pressures, manage limited energy resources and coexist with animals in the hadal zone, as well as technical developments in the exploration of hadal microbial life.

Binary combinatorial scanning reveals potent poly-alanine-substituted inhibitors of protein-protein interactions.

Establishing structure-activity relationships is crucial to understand and optimize the activity of peptide-based inhibitors of protein-protein interactions. Single alanine substitutions provide limited information on the residues that tolerate simultaneous modifications with retention of biological activity. To guide optimization of peptide binders, we use combinatorial peptide libraries of over 4,000 variants-in which each position is varied with either the wild-type residue or alanine-with a label-free affinity selection platform to study protein-ligand interactions. Applying this platform to a peptide binder to the oncogenic protein MDM2, several multi-alanine-substituted analogs with picomolar binding affinity were discovered. We reveal a non-additive substitution pattern in the selected sequences. The alanine substitution tolerances for peptide ligands of the 12ca5 antibody and 14-3-3 regulatory protein are also characterized, demonstrating the general applicability of this new platform. We envision that binary combinatorial alanine scanning will be a powerful tool for investigating structure-activity relationships.

Correction to: Structure and function of the Arctic and Antarctic marine microbiota as revealed by metagenomics.

An amendment to this paper has been published and can be accessed via the original article.

Structure and function of the Arctic and Antarctic marine microbiota as revealed by metagenomics.

BACKGROUND: The Arctic and Antarctic are the two most geographically distant bioregions on earth. Recent sampling efforts and following metagenomics have shed light on the global ocean microbial diversity and function, yet the microbiota of polar regions has not been included in such global analyses. RESULTS: Here a metagenomic study of seawater samples (n = 60) collected from different depths at 28 locations in the Arctic and Antarctic zones was performed, together with metagenomes from the Tara Oceans. More than 7500 (19%) polar seawater-derived operational taxonomic units could not be identified in the Tara Oceans datasets, and more than 3,900,000 protein-coding gene orthologs had no hits in the Ocean Microbial Reference Gene Catalog. Analysis of 214 metagenome assembled genomes (MAGs) recovered from the polar seawater microbiomes, revealed strains that are prevalent in the polar regions while nearly undetectable in temperate seawater. Metabolic pathway reconstruction for these microbes suggested versatility for saccharide and lipids biosynthesis, nitrate and sulfate reduction, and CO2 fixation. Comparison between the Arctic and Antarctic microbiomes revealed that antibiotic resistance genes were enriched in the Arctic while functions like DNA recombination were enriched in the Antarctic. CONCLUSIONS: Our data highlight the occurrence of dominant and locally enriched microbes in the Arctic and Antarctic seawater with unique functional traits for environmental adaption, and provide a foundation for analyzing the global ocean microbiome in a more complete perspective. Video abstract.

Graphene oxide membrane as an efficient extraction and ionization substrate for spray-mass spectrometric analysis of malachite green and its metabolite in fish samples.

A graphene oxide (GO) nanosheet-modified N+-nylon membrane (GOM) has been prepared and used as an extraction and spray-ionization substrate for robust mass spectrometric detection of malachite green (MG), a highly toxic disinfectant in liquid samples and fish meat. The GOM is prepared by self-deposition of GO thin film onto an N+-nylon membrane, which has been used for efficient extraction of MG in aquaculture water samples or homogenized fish meat samples. Having a dissociation constant of 2.17 × 10-9 M-1, the GOM allows extraction of approximately 98% of 100 nM MG. Coupling of the GOM-spray with an ion-trap mass spectrometer allows quantitation of MG in aquaculture freshwater and seawater samples down to nanomolar levels. Furthermore, the system possesses high selectivity and sensitivity for the quantitation of MG and its metabolite (leucomalachite green) in fish meat samples. With easy extraction and efficient spray ionization properties of GOM, this membrane spray-mass spectrometry technique is relatively simple and fast in comparison to the traditional LC-MS/MS methods for the quantitation of MG and its metabolite in aquaculture products.

Celastrol targets IRAKs to block Toll-like receptor 4-mediated nuclear factor-κB activation / 中西医结合学报

<p><b>OBJECTIVE</b>Celastrol has been established as a nuclear factor-κB (NF-κB) activation inhibitor; however, the exact mechanism behind this action is still unknown. Using text-mining technology, the authors predicted that interleukin-1 receptor-associated kinases (IRAKs) are potential celastrol targets, and hypothesized that targeting IRAKs might be one way that celastrol inhibits NF-κB. This is because IRAKs are key molecules for some crucial pathways to activate NF-κB (e.g., the interleukin-1 receptor (IL-1R)/Toll-like receptor (TLR) superfamily).</p><p><b>METHODS</b>The human hepatocellular cell line (HepG2) treated with palmitic acid (PA) was used as a model for stimulating TLR4/NF-κB activation, in order to observe the potential effects of celastrol in IRAK regulation and NF-κB inhibition. The transfection of small interfering RNA was used for down-regulating TLR4, IRAK1 and IRAK4, and the Western blot method was used to detect changes in the protein expressions.</p><p><b>RESULTS</b>The results showed that celastrol could effectively inhibit PA-caused TLR4-dependent NF-κB activation in the HepG2 cells; PA also activated IRAKs, which were inhibited by celastrol. Knocking down IRAKs abolished PA-caused NF-κB activation.</p><p><b>CONCLUSION</b>The results for the first time show that targeting IRAKs is one way in which celastrol inhibits NF-κB activation.</p>

Study on the efficacy and safety of sublingual immunotherapy with standardized dermatophagoides farinae drops for allergic rhinitis / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To evaluate the efficacy and safety of the sublingual immunotherapy with dermatophagoides farinae drops on patients with allergic rhinitis.@*METHOD@#One hundred and twelve cases were collected from adult patients with dust-mite allergic rhinitis of our hospital who could adhere to treatment and regular follow-up. These patients were randomly allocated to receive either sublingual immunotherapy (SLIT group, n = 56) or medical treatment (Control group, n = 56). To evaluate the clinical efficacy by side effects which were registered, symptom and medication scores which were assessed and rhinoconjunctivitis quality of life questionnaire (RQLQ) which was completed in the baseline and two years after treatment.@*RESULT@#Dropouts after the 2 years' treatment were 5 of SLIT group and 4 of Control group respectively. SLIT group induced the significant reductions on both the symptom scores (7.81 ± 3.14 to 3.89 ± 2.01, P < 0.0 1) and the medication scores (2.86 ± 0.75 to 0.44 ± 0.06, P < 0.01). Meanwhile, Control group induced the reductions on both the symptom scores (8.01 ± 3.32 to 5.20 ± 2.43) and the medication scores (2.95 ± 0.80 to 1.75 ± 0.40). There were significant differences (P< 0. 01) in symptom and medication scores between the two groups after 2-year treatment. The patients in SLIT group had fewer symptoms and lower intake of medication. There were statistically significant differences in RQLQ between SLIT group [19 (15,22)] and Control group [36 (26,47)] after two years treatment (Z = -5. 21, P < 0.01). SLIT group also had significant improvement in RQLQ (Z = -6.10, P < 0.01) between before and after the treatment. There were 4 patients who showed adverse reactions in SLIT group (3 occurred in increment period, and 1 occurred in the maintenance period). The incidence of adverse reactions was 7.14%. No severe systemic side effects were registered.@*CONCLUSION@#SLIT with standardized dermatophagoides farinae drops in China is safe and effective to patients with allergic rhinitis.

The management of 53 non-pituitary lesions in sphenoidal sinus by transnasal endoscopic surgery / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To investigate the diagnosis and management of non-pituitary lesions in sphenoidal sinus.@*METHOD@#All cases with non-pituitary lesions in sphenoidal sinus were confirmed by CT scan. Eight cases with localized lesions underwent operation by trans-sphenoidal approach. Two cases with juvenile nasopharyngeal angiofibroma with invasion to the sphenoid sinus were treated by trans-septal approach. The rest received operation by trans-superior meatal or trans-ethmoidal approach.@*RESULT@#Forty-five of these cases underwent complete or major resection of the lesion by endoscopic sphenoid sinus surgery, including 23 cyst and pus cyst of sphenoidal sinus, 8 fungal sphenoid sinusitis, 2 bleeding polyp of sphenoidal sinus, 1 post- hypophysectomy granulation hyperplasia of sphenoidal sinus , 5 papilloma of sphenoid sinus, 1 cerebrospinal rhinorrhea of sphenoid sinus, 2 ossified fibroma of sphenoid sinus,2 juvenile nasopharyngeal angiofibroma with invasion to the sphenoid sinus, 1 meningioma of ethmoid and sphenoid sinus. Three cases with hematoma in sphenoidal sinus and pseudoaneurysm in internal carotid artery underwent nasal endoscopic examination, and the diagnosis was established by DSA, and they received interventional therapy. Three cases with malignancy of sphenoidal sinus received major mass resection of sphenoidal sinus by trans-ethmoidal approach, and followed with radio therapy and chemotherapy. Two cases with NPC involving sphenoidal sinus were treated by radio therapy and chemotherapy after pathological examination.@*CONCLUSION@#Headache and visual loss were two common symptoms for the lesions in sphenoidal sinus. Imaging study including CT, MRI and DSA is very important for the diagnosis of the lesions in sphenoidal sinus. There are various surgical pathways to deal with sphenoidal sinus diseases under nasal endoscope. The operation will be direct, safe and minimal invasive if we choose the pathway properly.

Determination of C21 steroidal glycosides in Marsdenia tenacissima by colorimetric method / 中国中药杂志

<p><b>OBJECTIVE</b>To establish a quantitative method to deter mine C21 steroidal glycosides in Marsdenia tenacissima.</p><p><b>METHOD</b>Methanol was used as the extraction solvent and the samples were purified by macroporous resin ADS-7. A mixture of sulfuric acid-methanol (4:1)was used as color-producing reagent. The absorbance was measured at 325 nm.</p><p><b>RESULT</b>There is a good linearity (r = 0.999 9, n = 6) within the range of 10.6-148.4 microg. The average recoveries of tenacissoside-H at different concentrations were 95.8% to 97.1% with RSD less than 2.4% (n = 5).</p><p><b>CONCLUSION</b>This method is reliable as a quantitative analytical method for the quality assessment of M. tenacissima.</p>