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Virus capsid proteins have various applications in diverse fields such as biotechnology, electronics, and medicine. In this study, the major capsid protein of bacilliform clavavitus APBV1, which infects the hyperthermophilic archaeon Aeropyrum pernix, was successfully expressed in Escherichia coli. The gene product was expressed as a histidine-tagged protein in E. coli and purified to homogeneity using single-step nickel affinity chromatography. The purified recombinant protein self-assembled to form bacilliform virus-like particles at room temperature. The particles exhibited tolerance against high concentrations of organic solvents and protein denaturants. In addition, we succeeded in fabricating functional nanoparticles with amine functional groups on the surface of ORF6-81 nanoparticles. These robust protein nanoparticles can potentially be used as a scaffold in nanotechnological applications.

To examine whether MRCP using a combination of compressed sensing and sensitivity encoding with navigator-triggered and breath-hold techniques (NT C-SENSE and BH C-SENSE, respectively) have comparable image quality to that of navigator-triggered MRCP using only sensitivity encoding (NT SENSE) at 1.5-T. Fifty-one participants were enrolled in this prospective study between July and October 2018 and underwent the three 3D MRCP sequences each. The acquisition time and relative duct-to-periductal contrast ratios (RC values) of each bile duct segment were obtained. Visualization of the bile and main pancreatic ducts, background suppression, artifacts, and overall image quality were scored on 5-point scales. Mean and median differences in RC values and qualitative scores of NT C-SENSE and BH C-SENSE relative to NT SENSE were calculated with 95% confidence intervals (CIs). Acquisition time of NT SENSE, NT C-SENSE, and BH C-SENSE were 348, 143 (mean for both), and 18 s (for all participants), respectively. The RC value of each bile duct segment was inferior, but the lower limits of the 95% CIs of the mean differences were ≥ − 0.10, for both NT C-SENSE and BH C-SENSE. The visualization score of the intrahepatic duct in BH C-SENSE was inferior to that in NT SENSE (lower 95% CI limit, − 1.5). In both NT C-SENSE and BH C-SENSE, the 95% CIs of the median differences in the other qualitative scores were from − 1.0 to 0.0. NT C-SENSE and BH C-SENSE have comparable image quality to NT SENSE at 1.5-T.

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Searching for life in the Universe depends on unambiguously distinguishing biological features from background signals, which could take the form of chemical, morphological, or spectral signatures. The discovery and direct measurement of organic compounds unambiguously indicative of extraterrestrial (ET) life is a major goal of Solar System exploration. Biology processes matter and energy differently from abiological systems, and materials produced by biological systems may become enriched in planetary environments where biology is operative. However, ET biology might be composed of different components than terrestrial life. As ET sample return is difficult, in situ methods for identifying biology will be useful. Mass spectrometry (MS) is a potentially versatile life detection technique, which will be used to analyze numerous Solar System environments in the near future. We show here that simple algorithmic analysis of MS data from abiotic synthesis (natural and synthetic), microbial cells, and thermally processed biological materials (lab-grown organisms and petroleum) easily identifies relational organic compound distributions that distinguish pristine and aged biological and abiological materials, which likely can be attributed to the types of compounds these processes produce, as well as how they are formed and decompose. To our knowledge this is the first comprehensive demonstration of the utility of this analytical technique for the detection of biology. This method is independent of the detection of particular masses or molecular species samples may contain. This suggests a general method to agnostically detect evidence of biology using MS given a sufficiently strong signal in which the majority of the material in a sample has either a biological or abiological origin. Such metrics are also likely to be useful for studies of possible emergent living phenomena, and paleobiological samples.

We newly developed a rotating disk electrode-online electrochemical mass spectrometry (RDE-OLEMS) to investigate potential-dependent molecular behaviors in electrode surface vicinity under mass transport-controlled conditions of reacting molecules. The potential-dependent molecular behaviors were investigated by using a quadrupole mass spectrometer (Q-mass) where the molecules are collected through a gas-sampling tip located in near the electrode surface. For the oxygen reduction reaction (ORR) on the polycrystalline Pt electrode, the potential-dependent Q-mass ion signal intensities of O2 (m/z = 32) that are ascribable to the dissolved oxygen molecules increased linearly with the disk electrode rotation rates without substantial interference from the collection tip, clearly showing that the dissolved O2 for ORR can be monitored by the RDE-OLEMS. For electrochemical carbon dioxide reduction (ECR) on the polycrystalline Au electrode, the potential-dependent Q-mass ion signal intensities of CO (m/z = 28) generated by the ECR increased with increasing disk rotation rates from 0 (without disk rotation) to 300 rpm in the potential region from −0.4 to −1.4 V vs. the reversible hydrogen electrode. The results demonstrate that the RDE-OLEMS enables us to evaluate the potential-dependent behaviors of reactant and product molecules present near the electrode surface under the mass transport-controlled condition.

International audience; Tristromaviridae is a family of viruses with linear, double-stranded DNA genomes of 16-18 kbp. The flexible, filamentous virions (400±20 nm×30±3 nm) consist of an envelope and an inner core constructed from two structural units: a rod-shaped helical nucleocapsid and a nucleocapsid-encompassing matrix protein layer. Tristromaviruses are lytic and infect hyperthermophilic archaea of the order Thermoproteales. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the Tristromaviridae, which is available at www.ictv.global/report/tristromaviridae.

Viruses are the most abundant biological entities on modern Earth. They are highly diverse both in structure and genomic sequence, play critical roles in evolution, strongly influence terran biogeochemistry, and are believed to have played important roles in the origin and evolution of life. However, there is yet very little focus on viruses in astrobiology. Viruses arguably have coexisted with cellular life-forms since the earliest stages of life, may have been directly involved therein, and have profoundly influenced cellular evolution. Viruses are the only entities on modern Earth to use either RNA or DNA in both single- and double-stranded forms for their genetic material and thus may provide a model for the putative RNA-protein world. With this review, we hope to inspire integration of virus research into astrobiology and also point out pressing unanswered questions in astrovirology, particularly regarding the detection of virus biosignatures and whether viruses could be spread extraterrestrially. We present basic virology principles, an inclusive definition of viruses, review current virology research pertinent to astrobiology, and propose ideas for future astrovirology research foci. Key Words: Astrobiology-Virology-Biosignatures-Origin of life-Roadmap. Astrobiology 18, 207-223.

We examined the effects of mass sedimentation events caused by the 2011 off the Pacific coast of Tohoku Earthquake on abundances and vertical distributions of prokaryotes and metazoan meiofauna in sediments, using sediment cores collected from eight bathyal stations off Tohoku 1 year after the M9.0 earthquake. Event deposits 1–7 cm thick were observed at the topmost part of the sediment cores at all sampling stations. At some stations, prokaryotic cell abundances were lower in the surface event-deposit layers compared to those in deeper sediments. These variations were explained by environmental parameters such as a dimensionless sorting factor and mean grain size, suggesting that turbidite sedimentation affected prokaryotic cell abundances. Nematodes had anomalously higher subsurface abundances at the stations where subsurface peak prokaryotic cell numbers were observed, whereas copepods always showed peak densities in the sediment surface layer. Although there are no available data for prokaryotic cell abundances and meiofaunal densities before the earthquake from the same sites, it is likely that the subsurface peaks in prokaryotic cell numbers and nematode densities resulted from the sedimentation events. The effects of sedimentation events on the organisms were observed 1 year after the earthquake, indicating that episodic sedimentation events on scales of several centimeters have a large effect on small organisms inhabiting sediments.

Eukarya is thought to have arisen from one of the archaeal lineages between 2500–2000 mya. Recently, various metagenomic data revealed that the diversity of the domain archaea is far more complicated than previously thought, and which archaeal lineage served as the ancestor of the eukaryal lineage is currently under heated debate. Many archaeal viruses have been isolated in the past couple of decades, and have shown us their extensive morphological diversity. On the other hand, so-called “giant viruses” infecting eukaryal cells have been isolated from various aquatic environments since 2003. Molecular phylogenetic analysis revealed that giant viruses and eukarya have evolved with the interaction with each other via horizontal gene transfer (HGT). Interaction between archaeal-eukaryal cell lineages and their viruses may provide clues to explain the origin of eukarya from the archaeal ancestors.

Introduction Oxygen reduction reaction (ORR) is one of the important electro-catalytic reactions, because of its practical application for the cathode of polymer electrolyte fuel cells (PEFCs). The rotating ring-disk electrode (RRDE) method provides us information on applied-potential-dependent redox phenomena that proceed at the electrode surface and, has been widely used for studying ORR kinetics of the various electrodes. In contrast, few studies have been reported for dynamic behaviors of dissolved O2 molecules in electrolytes during ORR. In this study, we combine the online electrochemical mass spectrometry (OLEMS) [1] with the rotating disk electrode (RDE) method (RDE-OLEMS) to investigate potential-dependent phenomena for the dissolved O2 present in immediate vicinity of the Pt electrode during ORR. Experimental Fig.1(a) presents a schematic representation of the newly developed RDE-OLEMS system to analyze dissolved O2 present in the vicinity of a Pt working disk electrode (ø5mm, t = 4mm). The alumina polished Pt polycrystalline electrode was set into a RDE set-up. Then, the RDE-OLEMS measurements were performed in O2-saturated 0.1 M HClO4 with given disk rotation rates. Dissolved O2 molecules presented in the vicinity of the electrode surface was collected through a porous Teflon to prevent introduction of aqueous components into the vacuum system. During the RDE-OLEMS measurements, the distance between a PEEK Tip and Pt electrode surface was set to be ca. 50 µm by using a micrometer. The collected O2 was introduced into a quadrupole mass spectrometer (Q-mass) and, then, applied-potential-dependent O2 ion current (m/z=32) was recorded and compared with corresponding linear sweep voltammogram (LSV). Results and Discussion Fig.1(b) shows LSV curves of the Pt electrode recorded at anodic-potential-sweep (10 mV/s from 0.0 to 1.1 V vs. RHE) with the PEEK Tip configuration (Fig.1(a)). The LSV curves clearly showed diffusion-limiting currents in the potential region of 0.2 to 0.6 V: the Levich plots (inset) indicates that current densities change linearly with a square-route of the disk rotation rates. The results show that the dissolved O2 molecules can be supplied to the electrode surface in the developed RDE-OLEMS layout (with the PEEK Tip located at ca. 50 µm from the electrode surface). Fig.1(c) shows the RDE-OLEMS results (red) for the collected O2 (m/z=32) recorded at cathodic-potential-sweep from 1.05 to 0.05 V with a scan rate of 0.5 mV/s and a disk rotation rate of 1200 rpm. A simultaneously recorded LSV curve (cathodic-potential-sweep; black) is shown as a reference. It can be clearly seen that the applied-potential-dependent change in O2 ion current (MSCV) well corresponds to the LSV curve. The results clearly indicate that concentration of the dissolved O2 present in the vicinity of the electrode decrease with increasing ORR currents, especially in the diffusion limiting current region. In our poster presentation, we will discuss the results of RDE-OLEMS measurements for Pt and Pt-based alloy single crystal surfaces. Acknowledgement This work was partly supported by a Grant-in-Aid for scientific research (A) from the Japan society for the promotion of science (T. W.). References [1] A. H. Wonders et al., Journal of Applied Electrochemistry 36 (2006) 1215-1221. Fig.1 (a)Schematics of RDE-OLEMS system and PEEK Tip. Inset; magnified image around the PEEK Tip. (b)Anodic sweep LSV curves for ORR. inset; Levich plot. (c)RDE-OLEMS results for O2 (red; m/z=32) and corresponding LSV (Black). Figure 1

International audience; We have surveyed the morphological diversity of viruses infecting the archaeon Aeropyrum pernix, the most thermophilic species among aerobic organisms, growing optimally at 90 degrees C, and isolated and characterized a novel virus, Aeropyrum pernix bacilliform virus 1, APBV1. This is the first virus to be described of the genus Aeropyrum and the archaeal order Desulfurococcales. The virion of APBV1 has rigid bacilliform morphology, about 140x20nm, with one end pointed and the other rounded. It contains highly glycosylated single major protein and three minor proteins. The circular, double-stranded DNA genome comprising 5278bp is the smallest for known archaeal viruses. None of the 14 putative genes, all on the same DNA strand, shows significant similarity to sequences in the public databases. The APBV1 infection caused neither retardation of host growth nor lysis of host cells, and integration of the viral genome into the host chromosome was not detected. On the basis of unusual morphological and genomic properties, we propose to consider APBV1 as the first representative of a new viral family, the Clavaviridae.

Determining the nature of the viral genome is one of the first steps in characterization of any new virus. However, in the case of viruses with a single-stranded genome, it is not always simple to identify its orientation. In this study, a rapid, sensitive and simple PCR-based method is described to identify the strand orientation of single-stranded viral genomes. This method has been tested on the single-stranded DNA viruses, M13 and phiX174.

Background: The Canadian Paediatric Triage and Acuity Scale (P-CTAS) is used and modified at hospitals as a triage tool for pediatric patients before they are seen in emergency rooms. Pediatric surgery patients account for very few of the many patients in emergency departments, but they should be triaged as emergency or urgent because they might be candidates for surgery. Problems with and improvements for triaging pediatric surgery patients using the P-CTAS were studied. Methods: This retrospective study evaluated all patients 2 years old are triaged as level IV and they accounted for 12% of patients with possible intussusception in this study. A category of ‘possible intussusception’ should be made for level II. Most patients with acute scrotum, whether operated on or not, were level III. ‘Red or purple color of scrotal skin’ and/or ‘within 6 h from onset’ could be added to level II for patients with acute scrotum. Conclusions: P-CTAS worked well for pediatric surgery patients, and it needs to be modified and improved for such patients based on these results.

The Canadian Paediatric Triage and Acuity Scale (P-CTAS) is used and modified at hospitals as a triage tool for pediatric patients before they are seen in emergency rooms. Pediatric surgery patients account for very few of the many patients in emergency departments, but they should be triaged as emergency or urgent because they might be candidates for surgery. Problems with and improvements for triaging pediatric surgery patients using the P-CTAS were studied.This retrospective study evaluated all patients16 years old who visited the emergency department of Kyorin University Hospital during an approximately 4 year period between 1 May 2005, and 11 February 2009. Pediatric surgery patients were divided into two groups to evaluate the efficiency of P-CTAS triage. Patients who needed emergency treatment were in group A, and the others were in group B.Most group A patients were level I, II, or III (97%, 111/114). In contrast, 60% (71/119) of group B patients were level IV or greater. Some problems with and suggestions for the P-CTAS were identified. Many patients with trauma were under 1 year of age, and many with a foreign body were under 2 years of age. Age categories should be added for patients with trauma or foreign body aspiration. Patients with abdominal pain, and without anal bleeding or vomiting who are2 years old are triaged as level IV and they accounted for 12% of patients with possible intussusception in this study. A category of 'possible intussusception' should be made for level II. Most patients with acute scrotum, whether operated on or not, were level III. 'Red or purple color of scrotal skin' and/or 'within 6 h from onset' could be added to level II for patients with acute scrotum.P-CTAS worked well for pediatric surgery patients, and it needs to be modified and improved for such patients based on these results.

Over the past 19 years we have operated on 269 patients with myelopathy associated with cervical spondylosis. We report our results in 191 cases which we have followed up for 1 to 12 years (average 31 months). The clinical state before and after operation was recorded using the criteria of the Japanese Orthopaedic Association. Posterior operations gave better results than anterior for the more advanced myelopathies such as transverse lesions, the Brown-Sequard syndrome and the motor syndromes, but the brachialgia and cord syndrome and the central cord syndrome were satisfactorily treated by anterior operations. Of the three anterior and three posterior techniques used, no single one showed an overall superiority. A short duration of symptoms before operation was associated with better results, but these were not influenced by the age of the patients.

Thirty one patients suffering from myelopathy associated with ossification of the posterior longitudinal ligament and ligamentum flavum of the spine have been investigated. The pattern of spinal and peripheral hyperostosis was recorded in each case. Flowing anterior vertebral hyperostosis and ligamentous ossification at the enthesis around the pelvis and hips were the most frequent associations, occurring in approximately 86% of patients. The distribution and incidence of the spinal and extraspinal hyperostosis in this series corresponds closely to the findings in diffuse idiopathic skeletal hyperostosis (DISH). The present findings indicate that patients suffering from cervical myelopathy and ossification of the posterior longitudinal ligament should be regarded as manifesting focal features of a more generalised disorder producing skeletal hyperostosis.

Hypertension and hyperoxia combined with hypercarbia, which in previous studies had been found to improve post-traumatic spinal cord hypoxia but to have no therapeutic effects when applied 3 h after injury, were used for 3 h beginning immediately after trauma in dogs subjected to experimental cord injury, separately and in combination. For comparison of the effects of different anesthetic agents 2 control groups with barbiturate anesthesia and halothane anesthesia were also investigated. The experimental animals were examined neurologically and electrophysiologically for one week. It was concluded that hypertension as well as hyperoxia accompanied by hypercarbia, combined or alone, had no aborting effect against the post-traumatic progress of intramedullary damage. Rather, hypertension was presumed to work adversely by worsening intramedullary hemorrhage. Neither was any beneficial effect of barbiturate on acute spinal cord injury verified.

Combined hypertension and hypercarbia, which was found to improve post-traumatic spinal cord hypoxia and presumably ischemia in our previous study, was used in dogs subjected to experimental spinal cord injury to determine its therapeutic effects against acute spinal cord trauma. Intermittent hypertension and hypercarbia therapy, in which 15 minutes of hypertension and 95% O2:5% CO2 gas ventilation were alternated with 10 minutes of air ventilation, was given for 3 hours beginning 3 hours after injury. The treated dogs and untreated control dogs were checked neurologically and electrophysiologically at weekly intervals for up to 8 weeks. The treated dogs showed higher grades of neurological function within 1 week, but the results were statistically insignificant. Both groups demonstrated steady neurological improvement for the next 2 weeks and remained paraparetic thereafter with no group difference. The size of the intramedullary lesion was identical in both groups. Recovery of the somatosensory evoked potentials coincided well with neurological improvement, with again no difference between the two groups.

Spinal cord tissue oxygen was measured by polarography at the dorsum of the spinal cord for 24 hours after acute spinal cord injury, and the effects of hypertension, hypercarbia, and hyperoxia were examined. Acute spinal cord injury was produced in mongrel dogs by constriction of the midthoracic cord with an epidural tourniquet inflated to 400 mm Hg, which was maintained for 5 minutes. At the injury site spinal cord tissue oxygen was slightly increased immediately after injury but was depressed significantly at 1 hour and remained unchanged thereafter. Hypertension induced by the intravenous infusion of norepinephrine elevated the tissue oxygen only slightly after 3 hours. Hypercarbia and hyperoxia produced by ventilation with a 95% O2:5% CO2 mixture did not elevate the depressed spinal cord oxygen content. When hypertension, hypercarbia, and hyperoxia were combined, the spinal cord oxygen value was elevated to the normal level even at 3 hours after injury, when the cord oxygen was at its lowest, and it increased steadily thereafter.