Ribosomal protein s15 phosphorylation mediates LRRK2 neurodegeneration in Parkinson's disease.

Mutations in leucine-rich repeat kinase 2 (LRRK2) are a common cause of familial and sporadic Parkinson's disease (PD). Elevated LRRK2 kinase activity and neurodegeneration are linked, but the phosphosubstrate that connects LRRK2 kinase activity to neurodegeneration is not known. Here, we show that ribosomal protein s15 is a key pathogenic LRRK2 substrate in Drosophila and human neuron PD models. Phosphodeficient s15 carrying a threonine 136 to alanine substitution rescues dopamine neuron degeneration and age-related locomotor deficits in G2019S LRRK2 transgenic Drosophila and substantially reduces G2019S LRRK2-mediated neurite loss and cell death in human dopamine and cortical neurons. Remarkably, pathogenic LRRK2 stimulates both cap-dependent and cap-independent mRNA translation and induces a bulk increase in protein synthesis in Drosophila, which can be prevented by phosphodeficient T136A s15. These results reveal a novel mechanism of PD pathogenesis linked to elevated LRRK2 kinase activity and aberrant protein synthesis in vivo.

Identification of amino acid residue in the Cronobacter sakazakii LamB responsible for the receptor compatibility of polyvalent coliphage CSP1.

Polyvalent bacteriophages show the feature of infecting bacteria across multiple species or even orders. Infectivity of a polyvalent phage is variable depending on the host bacteria, which can disclose differential inhibition of bacteria by the phage. In this study, a polyvalent phage CSP1 infecting both Cronobacter sakazakii ATCC 29544 and Escherichia coli MG1655 was isolated. CSP1 showed higher growth inhibition and adsorption rate in E. coli compared to C. sakazakii, and identification of host receptors revealed that CSP1 uses E. coli LamB (LamBE) as a receptor but that CSP1 requires both C. sakazakii LamB (LamBC) and lipopolysaccharide (LPS) core for C. sakazakii infection. The substitution of LamBC with LamBE in C. sakazakii enhanced CSP1 susceptibility and made C. sakazakii LPS core no more essential for CSP1 infection. Comparative analysis of LamBC and LamBE disclosed that the extra proline at amino acid residue 284 in LamBC made a structural distinction by forming a longer loop and that the deletion of 284P in LamBC aligns its structure and makes LamBC function like LamBE, enhancing CSP1 adsorption and growth inhibition of C. sakazakii. These results suggest that 284P of LamBC plays a critical role in determining the CSP1-host bacteria interaction. These findings could provide insight into the elucidation of molecular determinants in the interaction between polyvalent phages and host bacteria and help us to understand the phage infectivity for efficient phage application. IMPORTANCE: Polyvalent phages have the advantage of a broader host range, overcoming the limitation of the narrow host range of phages. However, the limited molecular biological understanding on the host bacteria-polyvalent phage interaction hinders its effective application. Here, we revealed that the ability of the polyvalent phage CSP1 to infect Cronobacter sakazakii ATCC 29544 is disturbed by a single proline residue in the LamB protein and that lipopolysaccharide is used as an auxiliary receptor for CSP1 to support the adsorption and the subsequent infection of C. sakazakii. These results can contribute to a better understanding of the interaction between polyvalent phages and host bacteria for efficient phage application.

Tailoring Single-Electron Emission Distributions in the Time-Energy Phase Space.

The precise characterization and control of single-electron wave functions emitted from a single-electron source are essential for advancing electron quantum optics. Here, we introduce a method for tailoring a single-electron emission distribution using energy filtering, enabling selective control of the distribution under various energy barrier conditions of the filter. The tailored electron is studied by reconstructing its Wigner distribution in the time-energy phase space using the continuous-variable tomography method. Our results reveal that the filtering cuts the portion of the distribution below the energy-barrier height of the filter in the time-energy space. While the filtering is demonstrated in a classical regime of the emitted electrons, we expect that this study significantly contributes to the design and implementation of advanced experiments toward quantum information processing based on single electrons.

High-Throughput Quantitative Analysis of Amino Acids in Freeze-Dried Drops Using Time-of-Flight Secondary Ion Mass Spectrometry.

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) has become a promising analytical tool for molecular profiling in biological applications. However, its ultrahigh vacuum environment and matrix effects hamper the absolute quantitation of solution samples. Herein, we present a rapid high-throughput platform for quantitative ToF-SIMS analysis of amino acids in matrix deposits formed from freeze-dried solution drops through ice sublimation on a parylene film microarray substrate. Droplets of the amino acid solutions, which were mixed with stable isotope-labeled phenylalanine (F*) of high concentration (10 mM), were loaded on wells of the microarray, then frozen and evaporated slowly below the freezing point, forming continuous solid-phase F* matrix deposits. The amino acids (≤500 µM), adequately well dispersed throughout the F* matrix deposits on each well, were quantitatively analyzed by ToF-SIMS in a rapid and high-throughput fashion. The lower limit of quantitation reached below 10 µM.

Notch4 regulatory T cells and SARS-CoV-2 viremia shape COVID19 survival outcome.

BACKGROUND: Immune dysregulation and SARS-CoV-2 plasma viremia have been implicated in fatal COVID-19 disease. However, how these two factors interact to shape disease outcomes is unclear. METHODS: We carried out viral and immunological phenotyping on a prospective cohort of 280 patients with COVID-19 presenting to acute care hospitals in Boston, Massachusetts and Genoa, Italy between June 1, 2020 and February 8, 2022. Disease severity, mortality, plasma viremia, and immune dysregulation were assessed. A mouse model of lethal H1N1 influenza infection was used to analyze the therapeutic potential of Notch4 and pyroptosis inhibition in disease outcome. RESULTS: Stratifying patients based on %Notch4+ Treg cells and/or the presence of plasma viremia identified four subgroups with different clinical trajectories and immune phenotypes. Patients with both high %Notch4+ Treg cells and viremia suffered the most disease severity and 90-day mortality compared to the other groups even after adjusting for baseline comorbidities. Increased Notch4 and plasma viremia impacted different arms of the immune response in SARS-CoV-2 infection. Increased Notch4 was associated with decreased Treg cell amphiregulin expression and suppressive function whereas plasma viremia was associated with increased monocyte cell pyroptosis. Combinatorial therapies using Notch4 blockade and pyroptosis inhibition induced stepwise protection against mortality in a mouse model of lethal H1N1 influenza infection. CONCLUSIONS: The clinical trajectory and survival outcome in hospitalized patients with COVID-19 is predicated on two cardinal factors in disease pathogenesis: viremia and Notch4+ Treg cells. Intervention strategies aimed at resetting the immune dysregulation in COVID-19 by antagonizing Notch4 and pyroptosis may be effective in severe cases of viral lung infection.

Cntnap2-dependent molecular networks in autism spectrum disorder revealed through an integrative multi-omics analysis.

Autism spectrum disorder (ASD) is a major neurodevelopmental disorder in which patients present with core symptoms of social communication impairment, restricted interest, and repetitive behaviors. Although various studies have been performed to identify ASD-related mechanisms, ASD pathology is still poorly understood. CNTNAP2 genetic variants have been found that represent ASD genetic risk factors, and disruption of Cntnap2 expression has been associated with ASD phenotypes in mice. In this study, we performed an integrative multi-omics analysis by combining quantitative proteometabolomic data obtained with Cntnap2 knockout (KO) mice with multi-omics data obtained from ASD patients and forebrain organoids to elucidate Cntnap2-dependent molecular networks in ASD. To this end, a mass spectrometry-based proteometabolomic analysis of the medial prefrontal cortex in Cntnap2 KO mice led to the identification of Cntnap2-associated molecular features, and these features were assessed in combination with multi-omics data obtained on the prefrontal cortex in ASD patients to identify bona fide ASD cellular processes. Furthermore, a reanalysis of single-cell RNA sequencing data obtained from forebrain organoids derived from patients with CNTNAP2-associated ASD revealed that the aforementioned identified ASD processes were mainly linked to excitatory neurons. On the basis of these data, we constructed Cntnap2-associated ASD network models showing mitochondrial dysfunction, axonal impairment, and synaptic activity. Our results may shed light on the Cntnap2-dependent molecular networks in ASD.

Development of a Bacteriophage Cocktail against Pectobacterium carotovorum Subsp. carotovorum and Its Effects on Pectobacterium Virulence.

Pectobacterium carotovorum subsp. carotovorum is a necrotrophic plant pathogen that secretes plant cell wall-degrading enzymes (PCWDEs) that cause soft rot disease in various crops. Bacteriophages have been under consideration as harmless antibacterial agents to replace antibiotics and copper-based pesticides. However, the emergence of bacteriophage resistance is one of the main concerns that should be resolved for practical phage applications. In this study, we developed a phage cocktail with three lytic phages that recognize colanic acid (phage POP12) or flagella (phages POP15 and POP17) as phage receptors to minimize phage resistance. The phage cocktail effectively suppressed the emergence of phage-resistant P. carotovorum subsp. carotovorum compared with single phages in in vitro challenge assays. The application of the phage cocktail to napa cabbage (Brassica rapa subsp. pekinensis) resulted in significant growth retardation of P. carotovorum subsp. carotovorum (P < 0.05) and prevented the symptoms of soft rot disease. Furthermore, phage cocktail treatments of young napa cabbage leaves in a greenhouse environment indicated effective prevention of soft rot disease compared to that in the nonphage negative control. We isolated 15 phage-resistant mutants after a phage cocktail treatment to assess the virulence-associated phenotypes compared to those of wild-type (WT) strain Pcc27. All mutants showed reduced production of four different PCWDEs, leading to lower levels of tissue softening. Ten of the 15 phage-resistant mutants additionally exhibited decreased swimming motility. Taken together, these results show that the phage cocktail developed here, which targets two different types of phage receptors, provides an effective strategy for controlling P. carotovorum subsp. carotovorum in agricultural products, with a potential ability to attenuate P. carotovorum subsp. carotovorum virulence. IMPORTANCE Pectobacterium carotovorum subsp. carotovorum is a phytopathogen that causes soft rot disease in various crops by producing plant cell wall-degrading enzymes (PCWDEs). Although antibiotics and copper-based pesticides have been extensively applied to inhibit P. carotovorum subsp. carotovorum, the emergence of antibiotic-resistant bacteria and demand for harmless antimicrobial products have emphasized the necessity of finding alternative therapeutic strategies. To address this problem, we developed a phage cocktail consisting of three P. carotovorum subsp. carotovorum-specific phages that recognize colanic acids and flagella of P. carotovorum subsp. carotovorum. The phage cocktail treatments significantly decreased P. carotovorum subsp. carotovorum populations, as well as soft rot symptoms in napa cabbage. Simultaneously, they resulted in virulence attenuation in phage-resistant P. carotovorum subsp. carotovorum, which was represented by decreased PCWDE production and decreased flagellum-mediated swimming motility. These results suggested that preparations of phage cocktails targeting multiple receptors would be an effective approach to biocontrol of P. carotovorum subsp. carotovorum in crops.

Discovery of noncanonical translation initiation sites through mass spectrometric analysis of protein N termini.

Translation initiation generally occurs at AUG codons in eukaryotes, although it has been shown that non-AUG or noncanonical translation initiation can also occur. However, the evidence for noncanonical translation initiation sites (TISs) is largely indirect and based on ribosome profiling (Ribo-seq) studies. Here, using a strategy specifically designed to enrich N termini of proteins, we demonstrate that many human proteins are translated at noncanonical TISs. The large majority of TISs that mapped to 5' untranslated regions were noncanonical and led to N-terminal extension of annotated proteins or translation of upstream small open reading frames (uORF). It has been controversial whether the amino acid corresponding to the start codon is incorporated at the TIS or methionine is still incorporated. We found that methionine was incorporated at almost all noncanonical TISs identified in this study. Comparison of the TISs determined through mass spectrometry with ribosome profiling data revealed that about two-thirds of the novel annotations were indeed supported by the available ribosome profiling data. Sequence conservation across species and a higher abundance of noncanonical TISs than canonical ones in some cases suggests that the noncanonical TISs can have biological functions. Overall, this study provides evidence of protein translation initiation at noncanonical TISs and argues that further studies are required for elucidation of functional implications of such noncanonical translation initiation.

Simple SSMF-based two-channel MGDM system operating in the 0.8 µm wavelength region.

We propose a simple two-channel mode-group-division-multiplexing (MGDM) system operating in the 0.8 µm region over the standard single-mode fiber (SSMF). For the cost-effectiveness, we implement its receiver by using only two photodetectors (PDs) [instead of three PDs required for the detection of the LP01,LP11a, and LP11b modes]. We then detect the signal carried by the LP01 mode by using a PD and a mode filter. On the other hand, the other signal carried by the LP11 mode group is detected by using another PD and a multiple-input single-output equalizer (i.e., by subtracting the signal carried by the LP01 mode from the multiplexed signal). For a demonstration, we transmit 2×28Gb/s MGDM on-off keying signal operating at 852.6 nm over 2.2 km of the SSMF by using the proposed technique. The results show that we can achieve the bit-error rate of <3.8×10-3 for both the LP01 and LP11 modes.

Analysis of PET parameters as prognosticators of survival and tumor extent in Oropharyngeal Cancer treated with surgery and postoperative radiotherapy.

BACKGROUND: Positron-emission tomography (PET) is widely used to detect malignancies, but consensus on its prognostic value in oropharyngeal cancer has not been established. The purpose of this study was to analyze the PET parameters associated with tumor extent and survival in resectable oropharyngeal cancer. METHODS: The PET parameters in oropharyngeal cancer patients with regional node metastasis who underwent surgery and postoperative radiotherapy between January 2005 and January 2019 were analyzed. We calculated the SUVmax, tumor-to-liver ratio (TLR), metabolic tumor volume (MTV, volume over SUV 2.5), and total lesion glycolysis (TLG, MTV x mean SUV) of the primary lesion and metastatic nodes. Histologic findings, patient survival, and recurrence were reviewed in the medical records. RESULTS: Fifty patients were included, and the PET parameters were extracted for 50 primary lesions and 104 nodal lesions. In the survival analysis, MTV and TLG of the primary lesions showed significant differences in overall survival (OS) and recurrence-free survival (RFS). In the multiple regression analysis, TLG of the primary lesion was associated with the depth of invasion (DOI). MTV of the nodes was a significant factor affecting extranodal extension (ENE). CONCLUSIONS: PET parameters could be related with OS, RFS, DOI of the primary tumor, and ENE. PET would be expected to be a useful diagnostic tool as a prognosticator of survival and pathologic findings in oropharyngeal cancer.

Fluorescent paper strip immunoassay with carbon nanodots@silica for determination of human serum amyloid A1.

A fluorescent paper strip immunoassay in conjunction with carbon nanodots@silica (CND@SiO2) as a label was developed for the quantitative measurements of human serum amyloid A1 (hSAA1) in serum at clinically significant concentrations for lung cancer diagnosis. Monodispersed CND@SiO2 was prepared by cohydrolysis between silane-crosslinked carbon nanodots and silica precursors via the Ströber method and further attached covalently to anti-hSAA1 (14F8) monoclonal antibody [anti-hSAA1(14F8)] specific to the hSAA1 target. The hSAA1 concentrations were then determined by quantifying the blue fluorescence intensity upon 365 nm excitation of the captured hSAA1 with anti-hSAA1(14F8)-CND@SiO2 conjugates in the test line on a paper strip where anti-hSAA1 (10G1) monoclonal antibody was physisorbed. The developed fluorescent paper strip with CND@SiO2 can detect hSAA1 at concentrations ranging from 0.1 to 5 nM (R2 = 0.995), with a limit of detection of  0.258 nM in 10 mM phosphate buffer pH 7.4 containing human serum albumin. The performance of  recovery (90.98-109.17%) and repeatability (coefficients of variation < 8.46%) obtained was also acceptable for quantitative determinations. The platform was employed for direct determination of hSAA1 concentrations in undiluted serum samples from lung cancer patients (relative standard deviation (RSD) < 7.46%) and healthy humans (RSD < 3.96%). The results were compared with those obtained using a commercially available enzyme-linked immunosorbent assay alongside liquid chromatography with tandem mass spectrometry measurements.

Global Lysine Acetylome Analysis of LPS-Stimulated HepG2 Cells Identified Hyperacetylation of PKM2 as a Metabolic Regulator in Sepsis.

Sepsis-induced liver dysfunction (SILD) is a common event and is strongly associated with mortality. Establishing a causative link between protein post-translational modification and diseases is challenging. We studied the relationship among lysine acetylation (Kac), sirtuin (SIRTs), and the factors involved in SILD, which was induced in LPS-stimulated HepG2 cells. Protein hyperacetylation was observed according to SIRTs reduction after LPS treatment for 24 h. We identified 1449 Kac sites based on comparative acetylome analysis and quantified 1086 Kac sites on 410 proteins for acetylation. Interestingly, the upregulated Kac proteins are enriched in glycolysis/gluconeogenesis pathways in the Kyoto Encyclopedia of Genes and Genomes (KEGG) category. Among the proteins in the glycolysis pathway, hyperacetylation, a key regulator of lactate level in sepsis, was observed at three pyruvate kinase M2 (PKM2) sites. Hyperacetylation of PKM2 induced an increase in its activity, consequently increasing the lactate concentration. In conclusion, this study is the first to conduct global profiling of Kac, suggesting that the Kac mechanism of PKM2 in glycolysis is associated with sepsis. Moreover, it helps to further understand the systematic information regarding hyperacetylation during the sepsis process.

Craniofacial and dental injuries associated with stand-up electric scooters.

BACKGROUND/AIM: With the recent increased share of stand-up electric scooters (e-scooters), it is common to see people riding e-scooters on the roads in Korea. The aim of this study was to investigate traumatic injuries to the craniofacial region related to e-scooter accidents and to determine the role of dentists (especially oral and maxillofacial surgeons) in the evaluation of patients with trauma at the emergency department due to an e-scooter accident. MATERIALS AND METHODS: This retrospective study investigated the medical records of patients who visited the Gangnam Severance Hospital Emergency Care Center for trauma related to e-scooter use from January 1, 2017 to March 31, 2020. Medical records were reviewed to determine the injuries sustained to the craniofacial region related to e-scooter use, including location of the injury (eg, cranium, craniofacial bone, teeth, soft tissue) and the type of trauma (eg, fracture, laceration, abrasion, contusion, concussion). RESULT: A total of 256 patients' medical records were evaluated. Among them, 125 patients (48.8% of all patients) had sustained craniofacial trauma. Laceration (n = 56, 44.8%) was the most common type of craniofacial injury, followed by cerebral concussion (n = 49, 39.2%), dental injury (n = 27, 21.6%), and craniofacial bone fracture (n = 16, 12.8%). CONCLUSION: Dentists should always consider the possibility of brain trauma and perform a complete craniofacial and oral examination when assessing patients after e-scooter accidents as outlined by the International Association of Dental Traumatology guidelines. Additionally, it is necessary to educate e-scooter riders about the importance of wearing protective devices, such as helmets, to reduce the risk of injuries to the craniofacial region.

A User-Friendly Visualization Tool for Multi-Omics Data.

The Clinical Proteomic Tumor Analysis Consortium (CPTAC) initiative has generated large multi-omic datasets for various cancers. Each dataset consists of common and differential data types, including genomics, epigenomics, transcriptomics, proteomics, and post-translational modifications data. They together make up a rich resource for researchers and clinicians interested in understanding cancer biology to draw from. Nevertheless, the complexity of these multi-omic datasets and a lack of an easily accessible analytical and visualization tool for exploring them continue to be a hurdle for those who are not trained in bioinformatics. In this issue, Calinawan et al. describe a user-friendly, web-based visualization platform named ProTrack for exploring the CPTAC clear cell renal cell carcinoma (ccRCC) dataset. Compared to other available visualization tools, ProTrack offers an easy yet powerful customization interface, solely dedicated to the CPTAC ccRCC dataset. Their tool enables ready inspection of potential associations between different data types within a single gene or across multiple genes without any need to code. Specific mutation types or phosphosites can also be easily looked up for any gene of interest. Calinawan et al. aim to extend their work into other CPTAC datasets, which will greatly contribute to the CPTAC as well as cancer biology community in general.

Statistical Modeling for Enhancing the Discovery Power of Citrullination from Tandem Mass Spectrometry Data.

Citrullination is a post-translational modification implicated in various human diseases including rheumatoid arthritis, Alzheimer's disease, multiple sclerosis, and cancers. Due to a relatively low concentration of citrullinated proteins in the total proteome, confident identification of citrullinated proteome is challenging in mass spectrometry (MS)-based proteomic analysis. From these MS-based analyses, MS features that characterize citrullination, such as immonium ions (IMs) and neutral losses (NLs), called diagnostic ions, have been reported. However, there has been a lack of systematic approaches to comprehensively search for diagnostic ions and no statistical methods for the identification of citrullinated proteome based on these diagnostic ions. Here, we present a systematic approach to identify diagnostic IMs, internal ions (INTs), and NLs for citrullination from tandem mass (MS/MS) spectra. Diagnostic INTs mainly consisted of internal fragment ions for di- and tripeptides that contained two and three amino acids with at least one citrullinated arginine, respectively. A statistical logistic regression model was built for a confident assessment of citrullinated peptides that database searches identified (true positives) and prediction of citrullinated peptides that database searches failed to identify (false negatives) using the diagnostic IMs, INTs, and NLs. Applications of our model to complex global proteome data sets demonstrated the increased accuracy in the identification of citrullinated peptides, thereby enhancing the size and functional interpretation of citrullinated proteomes.

Toward the human cellular microRNAome.

MicroRNAs are short RNAs that serve as regulators of gene expression and are essential components of normal development as well as modulators of disease. MicroRNAs generally act cell-autonomously, and thus their localization to specific cell types is needed to guide our understanding of microRNA activity. Current tissue-level data have caused considerable confusion, and comprehensive cell-level data do not yet exist. Here, we establish the landscape of human cell-specific microRNA expression. This project evaluated 8 billion small RNA-seq reads from 46 primary cell types, 42 cancer or immortalized cell lines, and 26 tissues. It identified both specific and ubiquitous patterns of expression that strongly correlate with adjacent superenhancer activity. Analysis of unaligned RNA reads uncovered 207 unknown minor strand (passenger) microRNAs of known microRNA loci and 495 novel putative microRNA loci. Although cancer cell lines generally recapitulated the expression patterns of matched primary cells, their isomiR sequence families exhibited increased disorder, suggesting DROSHA- and DICER1-dependent microRNA processing variability. Cell-specific patterns of microRNA expression were used to de-convolute variable cellular composition of colon and adipose tissue samples, highlighting one use of these cell-specific microRNA expression data. Characterization of cellular microRNA expression across a wide variety of cell types provides a new understanding of this critical regulatory RNA species.

C9orf72 nucleotide repeat structures initiate molecular cascades of disease.

A hexanucleotide repeat expansion (HRE), (GGGGCC)n, in C9orf72 is the most common genetic cause of the neurodegenerative diseases amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Here we identify a molecular mechanism by which structural polymorphism of the HRE leads to ALS/FTD pathology and defects. The HRE forms DNA and RNA G-quadruplexes with distinct structures and promotes RNA•DNA hybrids (R-loops). The structural polymorphism causes a repeat-length-dependent accumulation of transcripts aborted in the HRE region. These transcribed repeats bind to ribonucleoproteins in a conformation-dependent manner. Specifically, nucleolin, an essential nucleolar protein, preferentially binds the HRE G-quadruplex, and patient cells show evidence of nucleolar stress. Our results demonstrate that distinct C9orf72 HRE structural polymorphism at both DNA and RNA levels initiates molecular cascades leading to ALS/FTD pathologies, and provide the basis for a mechanistic model for repeat-associated neurodegenerative diseases.

A draft map of the human proteome.

The availability of human genome sequence has transformed biomedical research over the past decade. However, an equivalent map for the human proteome with direct measurements of proteins and peptides does not exist yet. Here we present a draft map of the human proteome using high-resolution Fourier-transform mass spectrometry. In-depth proteomic profiling of 30 histologically normal human samples, including 17 adult tissues, 7 fetal tissues and 6 purified primary haematopoietic cells, resulted in identification of proteins encoded by 17,294 genes accounting for approximately 84% of the total annotated protein-coding genes in humans. A unique and comprehensive strategy for proteogenomic analysis enabled us to discover a number of novel protein-coding regions, which includes translated pseudogenes, non-coding RNAs and upstream open reading frames. This large human proteome catalogue (available as an interactive web-based resource at http://www.humanproteomemap.org) will complement available human genome and transcriptome data to accelerate biomedical research in health and disease.

Pressurized cultivation strategies for improved microbial hydrogen production by Thermococcus onnurineus NA1.

While the hydrogen economy is receiving growing attention, research on microbial hydrogen production is also increasing. Microbial water-gas shift reaction is advantageous as it produces hydrogen from by product gas including carbon monoxide (CO). However, CO solubility in water is the bottleneck of this process by low mass transfer. Thermococcus onnurineus NA1 strain can endure a high-pressure environment and can enhance hydrogen production in a pressurized reactor by increasing CO solubility. As CO causes cell toxicity, two important factors, pressure and input gas flow rate, should be considered for process control during cultivation. Hence, we employed different operational strategies for enhancing hydrogen production and obtained 577 mmol/L/h of hydrogen productivity. This is the highest hydrogen productivity reported to date from microbial water-gas shift reaction.

Transoral endoscopic thyroid surgery using robotic scope holder: Our initial experiences.

BACKGROUND: : Transoral thyroid surgery represented by the da Vinci system is attracted attention and performed by several institutions. However, the current available da Vinci system still has some limitations to be improved for transoral thyroid surgery including high cost of equipment and expendables, larger diameter scope and instruments and no tactile sensation. It triggered us interest in more easily available robotic scope holder. Soloassist II (AktorMed GmbH, Barbing, Germany) is an active endoscope holder system which is controlled by a joystick. It has total six joints: three joints which are controlled by computer, one is controlled by manual and two act as a gimbal joint following the movement of the main body. MATERIALS AND METHODS: We tried transoral endoscopic thyroidectomy using Soloassist II (AktorMed GmbH, Barbing, Germany) in December 2017 in our hospital. RESULTS: We successfully performed four thyroid lobectomies in four patients with Soloassist II. We refined and described surgical procedures in each step using video clips. It provided an excellent vibration-free stable surgical view which enabled fatigue-free work, without shaking or tilting the horizon. The surgeon could perform transoral endoscopic thyroid surgery with only one assistant surgeon. Docking and preparation time for Soloassist was within 10 min in all four patients. The setup and dismantling could be performed parallel to the usual workflow. No complication was reported by any patient. CONCLUSIONS: : The robotic scope holder (Soloassist II) seems to be safe and feasible equipment for performing transoral endoscopic thyroid surgery. Several possible advantages could be expected with this robotic scope holder.