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Surgery for T1b gastric cancer requires suprapancreatic nodes (SPA nodes) and perigastric nodes (PG nodes), however, SPA nodal dissection can cause pancreatic complications. If endoscopic treatment followed by additional surgery is planned, it may be possible to predict SPA nodal metastasis by analyzing the pathological information of the primary tumor in addition to the clinical findings.Patients who underwent D1+ or D2 and who were pathologically diagnosed with pT1b were retrospectively analyzed. The stations were divided into the nodes located at the perigastric area (PG nodes; #1-7) and the nodes located at the suprapancreatic area (SPA nodes; #8a-12a). The patients were classified into those with and without metastasis to the SPA nodes. Clinicopathological factors were investigated for their possible association with metastasis to the SPA nodes.A total of 2017 patients were examined in this study. Metastasis to the SPA nodes was observed in 80 patients (4%). In a multivariate analysis, undifferentiated histology, lower third, and lymphovascular invasion were independent risk factors for metastasis to the SPA nodes. The risk of metastasis to the SPA nodes waslt;2% in upper/middle tumors of differentiated type with no lymphovascular invasion and in lower tumors of undifferentiated type with no lymphovascular invasion. On the other hand, the risk of metastasis to the SPA nodes wasgt;10% in lower tumors of undifferentiated type with lymphovascular invasion.SPA nodal metastasis can be predicted when endoscopic treatment is initially planned. SPA nodal dissection should not be uniformly selected for T1b gastric cancer.

Aim Bacillus subtilis var. natto is used in the production of natto, a typical Japanese fermented soybean food. Although the probiotic attributes and health-related effects of B. subtilis var. natto have been reported, the effect on longevity remains unknown. In the present study, the effects of B. subtilis var. natto strains on lifespan extension and the molecular mechanisms governing the prolongevity were examined using Caenorhabditis elegans as a model animal. Methods and results Synchronized 3-day-old (young adult) worms were fed Escherichia coli OP50 (control) or a subcloned isolate of B. subtilis var. natto Miyagino strain (MI-OMU01) and subjected to lifespan, survival against pathogens and abiotic stress resistance assays. Notably, the lifespan of worms fed MI-OMU01 was significantly longer than that of the animals fed OP50. Moreover, MI-OMU01 increased the resistance of C. elegans to several stressors, including UV irradiation, H2O2, and Cu2+. Conclusions Genetic and gene expression analyses using mutant animals suggested that MI-OMU01 extended the lifespan of worms in TIR-1/SARM, p38 MAPK, and insulin/IGF-1 signaling pathway-dependent manners.

Mycobacterium tuberculosis, the causative agent of tuberculosis, possess flavin-dependent thymidylate synthase, ThyX. Since thyX is absent in humans and was shown to be essential for M. tuberculosis normal growth, ThyX is thought to be an attractive novel TB drug target. This study assessed thyX essentiality in Mycobacterium bovis BCG strains using CRISPR interference based gene silencing and found that thyX is not essential in an M. bovis BCG Tokyo derivative strain. A thyX deletion mutant strain was successfully constructed from that strain, which reinforces the non-essentiality of thyX under a certain genetic background.

Rats are an important maintenance host of Leptospira spp., the causative agents of leptospirosis, a zoonotic disease with worldwide distribution. Rats are traded as food in the Mekong Delta, where Cambodia exports tons of rats to Vietnam. Handling wild rats is a potential health risk, but the information on Leptospira spp. carried by rats traded in the region remains limited. In this study, we investigated the carriage of Leptospira spp. in rats exported from Cambodia to Vietnam using bacterial culture, nested PCR and DNA sequencing. Isolates were then assessed using serological analysis and whole-genome sequencing (WGS), and Leptospira DNA detected in rat kidney tissues was also analysed by multilocus sequence typing (MLST). Seventy-two rats (2 Bandicota indica, 57 Rattus argentiventer, 11 R. losea, 1 R. norvegicus and 1 R. rattus) were subjected to bacterial culture, and three L. borgpetersenii serogroup Javanica isolates were obtained from R. argentiventer (5.3%). WGS revealed that although Cambodian isolates were genetically related to L. borgpetersenii serogroup Javanica strains widely distributed in East and South-East Asian countries, they formed a different cluster from other strains. In addition to the three L. borgpetersenii sequences, the flaB sequence of L. interrogans was detected in 18 R. argentiventer and 7 R. losea kidney tissue samples (38.9%) using nested PCR followed by DNA sequencing. The L. interrogans flaB-positive samples were further analysed by MLST, revealing that seven housekeeping genes (glmU, pntA, sucA, tpiA, pfkB, mreA and caiB) contained novel sequences with distinct lineages from other sequence types. This study revealed a high prevalence of Leptospira spp. among rats exported from Cambodia to Vietnam, indicating a potential risk to people engaging in rat trade and demonstrating that a fastidious L. interrogans strain circulates among Cambodian rats.

Mycobacterium aviumsubsp.hominissuis(MAH) is one of the most prevalent mycobacteria causing non-tuberculous mycobacterial disease in humans and animals. Of note, MAH is a major cause of mycobacterial granulomatous mesenteric lymphadenitis outbreaks in pig populations. To determine the precise source of infection of MAH in a pig farm and to clarify the epidemiological relationship among pig, human and environmental MAH lineages, we collected 50 MAH isolates from pigs reared in Japan and determined draft genome sequences of 30 isolates. A variable number of tandem repeat analysis revealed that most pig MAH isolates in Japan were closely related to North American, European and Russian human isolates but not to those from East Asian human and their residential environments. Historical recombination analysis revealed that most pig isolates could be classified into SC2/4 and SC3, which contain MAH isolated from pig, European human and environmental isolates. Half of the isolates in SC2/4 had many recombination events with MAH lineages isolated from humans in East Asia. To our surprise, four isolates belonged to a new lineage (SC5) in the global MAH population. Members of SC5 had few footprints of inter-lineage recombination in the genome, and carried 80 unique genes, most of which were located on lineage specific-genomic islands. Using unique genetic features, we were able to trace the putative transmission route via their host pigs. Together, we clarify the possibility of species-specificity of MAH in addition to local adaptation. Our results highlight two transmission routes of MAH, one exposure on pig farms from the environment and the other via pig movement. Moreover, our study also warns that the evolution of MAH in pigs is influenced by MAH from patients and their residential environments, even if the MAH are genetically distinct.HighlightsVariable number of tandem repeat analysis ofMycobacterium aviumsubsp.hominissuis(MAH) isolated from pigs (n=50) were conducted.Draft genome sequences of MAH (n=30) and genome analysis were conducted.Pig MAHs were genetically far from East Asian human isolates and close to those of Western countries.Novel MAH lineage which were transmitted farms by pig movement was found.Human MAH isolates influenced the evolution of pig isolates.

Enterotoxigenic Escherichia coli (ETEC) strains that express various fimbrial or nonfimbrial colonisation factors (CFs) and enterotoxins are critical causes of diarrhoeal diseases. Human ETEC serotype O169:H41 (O169) has been a representative of epidemic ETEC worldwide; the organism shows massive adherence to HEp-2 cells similar to enteroaggregative E. coli. Previously, we determined the complete sequence of the unstable virulence plasmid, pEntYN10. The plasmid included a unique set of genes encoding a novel CF resembling K88 (F4) of porcine ETEC, in addition to CS6, a well-known representative CF of human ETEC, and another novel CF similar to CS8 (CFA/III) of human ETEC. In the present study, we focused on K88-like CF (hereafter, K88O169) that may allow the organisms to infect domestic livestock like original K88-harbouring strains that can cause diarrhoea in piglets. Samples were tested for antibodies against recombinant proteins of possible paralogous adhesins, FaeG1 and FaeG2, from K88O169 and the FaeG of typical K88 (F4). The seroepidemiological study using recombinant antigens (two paralogs FaeG1 and FaeG2 from K88O169) showed reactivity of porcine (18.0%) and bovine (17.1%) sera to K88O169 FaeG1 and/or FaeG2 antigens on indirect ELISA tests. These results suggest that E. coli with K88O169 adhesin can infect various hosts, including pigs and cattle. This is the first report of domestic livestock having antibodies to K88O169 of human ETEC. Although human ETEC had been thought to be distinguished from those of domestic animals based on CFs, zoonotic strains may conceal themselves among human ETEC organisms. The concept of One Health should be adopted to intervene in ETEC infections among animals and humans.

Mycobacterium avium subsp. hominissuis (MAH) is one of the most important agents causing non-tuberculosis mycobacterial infection in humans and pigs. There have been advances in genome analysis of MAH from human isolates, but studies of isolates from pigs are limited despite its potential source of infection to human. Here, we obtained 30 draft genome sequences of MAH from pigs reared in Japan. The 30 draft genomes were 4,848,678–5,620,788 bp in length, comprising 4652–5388 coding genes and 46–75 (median: 47) tRNAs. All isolates had restriction modification-associated genes and 185–222 predicted virulence genes. Two isolates had tRNA arrays and one isolate had a clustered regularly interspaced short palindromic repeat (CRISPR) region. Our results will be useful for evaluation of the ecology of MAH by providing a foundation for genome-based epidemiological studies.

Welfare game is a game-theoretic model for resource allocation problem which is to find an allocation to maximize the welfare function. In order to determine it in a distributed way, each agent is assigned to an admissible utility function such that the resulting game possesses desirable properties, for example, scalability, existence and efficiency of pure Nash equilibria, and budget balance. In this paper, supposing that each agent can access the global information, marginal contribution based utility design is proposed. It is shown that utility functions based on the above design have scalability and existence of pure Nash equilibria. Furthermore, efficiency is the same as that of the conventional utility design via Shapley value.

A graph Laplacian based distributed protocol that can achieve a group consensus over weighted, signed, directed, and weakly connected graphs is investigated. It is said to achieve the group consensus if the state of agents who belong to the same group converges to a common value, while the one of agents who belong to another group converges to a different value. It is assumed that no agent knows which group she belongs to before the protocol is executed. In this paper, for a given signed graph which contains a directed spanning tree, namely, at least one leader that can affect all of the other agents, a definition of n-structurally balanced is proposed. It is emphasized that this definition is a generalization of the structurally balanced which leads a bipartite consensus. Then, necessary and sufficient conditions are established to guarantee the agents’ state reaching the group consensus. The results are illustrated through numerical examples.

This paper proposes a trade-off approach between fatigue reduction and power extraction for wind farm scenarios, in which a simplified model for a Horizontal Axis Wind Turbine is developed. Both the aerodynamics and the electrical-mechanical model are implemented, considering a Doubly-Fed Induction Machine (DFIM). This model is controlled and connected to the grid by a back-to-back converter, composed of two bi-directional voltage source inverters. Moreover, the stator windings of the generator are directly linked to the grid and the rotor windings are connected to the grid through the power converter. The control of the VSIs is based on super-twisting sliding mode control, which guarantees robustness and low chattering effects. A wake model and an optimization problem for the reduction of the loads are included, to reduce the maximum fatigue load without compromising the power extraction. The results show a performance tracking of a desired rotational speed for the DFIMs and reduction of fatigue and damage, with a limited power reduction compared with the maximum power point tracking.

The ability to produce monokaryotic fruiting bodies and clamp cells in culture was examined in monokaryotic strain isolated from several dikaryotic parental strains of the edible mushroom, Mycoleptodonoides aitchisonii (Bunaharitake). We describe a single dikaryotic M. aitchisonii strain, TUFC50005, and 20 monokaryons derived from it, which exhibited a wide spectrum of monokaryotic fruiting types. Most strains formed primordia, or young fruiting body-like structures, but only one of the monokaryons, strain TUFC50005-4, formed a fruiting body, even though it had only one nucleus and produced only two spores after meiosis. We demonstrated that dikariotization was not required for clamp cell formation, fruiting body formation, or meiosis, in this mushroom.

Mycobacterium avium subsp. hominissuis (MAH) is one of the most important agents causing non-tuberculosis mycobacterial infection in humans and pigs. Genome analysis on MAH of human isolates has been proceeding, however, those of pigs are limited despite its potential source of infection to human. In the current study, we obtained 30 draft genome sequences of MAH of pigs reared in Japan. The 30 draft genomes consisted of 4,848,678 – 5,620,788 bp length, 4,652 – 5,388 coding genes and 46 – 75 (Med: 47) tRNAs. All isolates had restriction modification associated genes and 185 – 222 predicted virulence genes. Two isolates had tRNA arrays and one isolate had a clustered regularly interspaced short palindromic repeat (CRISPR) region. Our results will be useful for evaluation of the ecology of MAH by providing a foundation for genome-based epidemiological studies.

Staphylococcal enterotoxins (SEs) produced by enterotoxigenic Staphylococcus aureus in food cause staphylococcal food poisoning. We recently reported a foodborne outbreak due to S. aureus harboring new SE/SE-like (SEl) genes (seg, sei, sem, sen, seo, and selu) related to enterotoxin gene cluster (egc) 2 as with other research groups. However, the pathogenicity of SEs production remains unclear. Therefore, we herein investigated egc2-related SEs production from S. aureus isolates and leftover food items during a foodborne outbreak using a sandwich enzyme-linked immunosorbent assay suitable for the quantification of SEs. S. aureus isolates produced markedly high levels of egc2-related SEs, and the leftover food item “Sushi” contained SEs over the toxin dose that causes food poisoning symptoms. A representative isolate was subjected to whole-genome sequencing. The isolate was homologous with previously reported ST45 strains, particularly the unique genomic island νSaβ structure mostly consisting of egc2. The present study indicates that egc2-related SEs are food poisoning causative agents based on high SE production levels within an actual foodborne outbreak.

Enterotoxigenic Escherichia coli (ETEC) strains that express various fimbrial or nonfimbrial colonization factors and enterotoxins are critical causes of diarrheal diseases. Human ETEC serotype O169:H41 (O169) has been a representative of epidemic ETEC worldwide; the organism shows massive adherence to HEp-2 cells similar to enteroaggregative E. coli. Previously, we determined the complete sequence of the unstable virulence plasmid, pEntYN10. The plasmid included a unique set of genes encoding a novel colonization factor (CF) resembling K88 (F4) of porcine ETEC, in addition to CS6, a well-known representative CF of human ETEC, and another novel CF similar to CS8 (CFA/III) of human ETEC. To determine whether the K88-like CF (after this, K88O169) allows the organisms to infect domestic animals like the original K88-harboring strains that can cause diarrhea in piglets, samples were tested for antibodies against recombinant proteins of possible paralogous adhesins, FaeG1 and FaeG2, from K88O169 and the FaeG of typical K88 (F4). The seroepidemiological study using recombinant antigens (two paralogs FaeG1 and FaeG2 from K88O169) showed reactivity of porcine (18.0%) and bovine (17.1%) sera to K88O169 FaeG1 and/or FaeG2 antigens on indirect ELISA tests. These results suggest that E. coli with K88O169 adhesin can infect various hosts, including pigs and cattle. This is the first report of domestic animals having antibodies to K88O169 of human ETEC. Although human ETEC had been thought to be distinguished from those of domestic animals based on colonization factors, zoonotic strains may conceal themselves among human ETEC organisms. The concept of One Health should be adopted to intervene in ETEC infections among animals and humans.

Background Facing a global epidemic of new infectious diseases such as COVID-19, non-pharmaceutical interventions (NPIs), which reduce transmission rates without medical actions, are being implemented around the world to mitigate spreads. One of the problems in assessing the effects of NPIs is that different NPIs have been implemented at different times based on the situation of each country; therefore, few assumptions can be shared about how the introduction of policies affects the patient population. Mathematical models can contribute to further understanding these phenomena by obtaining analytical solutions as well as numerical simulations. Methods and results In this study, an NPI was introduced into the SIR model for a conceptual study of infectious diseases under the condition that the transmission rate was reduced to a fixed value only once within a finite time duration, and its effect was analyzed numerically and theoretically. It was analytically shown that the maximum fraction of infected individuals and the final size could be larger if the intervention starts too early. The analytical results also suggested that more individuals may be infected at the peak of the second wave with a stronger intervention. Conclusions This study provides quantitative relationship between the strength of a one-shot intervention and the reduction in the number of patients with no approximation. This suggests the importance of the strength and time of NPIs, although detailed studies are necessary for the implementation of NPIs in complicated real-world environments as the model used in this study is based on various simplifications.

Leptospirosis is one of the most prevalent zoonotic diseases caused by pathogenic spirochetes of Leptospira spp. The disease has become a public health concern in urban localities in the tropics, where rats serve as significant reservoir animals for leptospirosis transmission. In Indonesia, the occurrence of leptospirosis is underestimated, and information on the causative Leptospira genotypes and serotypes is limited. This study reports the isolation of Leptospira spp. from rats captured in urban areas of Bogor, Indonesia. Serogroups and genotypes, sequence types (STs), or multiple-locus variable-number tandem repeat analysis (MLVA) types using 11 loci, were determined for the isolates. Furthermore, whole genome sequencing (WGS) was performed on 11 Indonesian isolates and 24 isolates from other Asian countries. Ninety small mammals, including 80 Rattus norvegicus and ten Suncus murinus, were captured and, 25 Leptospira spp. were isolated solely from R. norvegicus (31.3%). The isolates were identified as Leptospira borgpetersenii serogroup Javanica with ST 143 (four strains) and Leptospira interrogans serogroup Bataviae with the same MLVA type as isolates from other Asian countries (19); the serogroup of the two L. interrogans with ST252 could not be identified. The core genome SNP-based phylogenetic tree revealed that Indonesian isolates were genetically related to L. borgpetersenii serogroup Javanica strains widely distributed in Asian countries but formed a different cluster from other strains. The phylogenetic tree of L. interrogans serogroup Bataviae isolates from Indonesia, the Philippines, Taiwan, and Vietnam revealed that isolates were grouped into five clusters based on their geographic locations. This study discovered a high carriage rate of Leptospira spp. among R. norvegicus in Bogor, Indonesia, indicating a potential risk of rat-borne leptospirosis in the area. Besides L. borgpetersenii serogroup Javanica, WGS on L. interrogans serogroup Bataviae illustrated the geographical structuring of genetic diversity in Leptospira spp.

Amikacin and colistin are effective against carbapenem-resistant Klebsiella pneumoniae. In 2017, we successively isolated three carbapenem-resistant K. pneumoniae isolates (ST967) from a patient with chronic renal failure in Japan. The first (SMKP01, sputum, day 0) and second (SMKP02, blood, day 14) strains were resistant to most antimicrobials tested but still susceptible to amikacin (MICs of 4 and 0.5 mg/liter, respectively) and colistin (MIC of 0.5 mg/liter for both). The third strain (SMKP03, blood, day 51) was not susceptible to amikacin (MIC, 32 mg/liter), and its MIC for colistin varied (0.5 to 8 mg/liter). Whole-genome sequencing of SMKP01 revealed that 17 of 20 antimicrobial resistance genes, including qnrB91 (a novel qnrB2 variant) and aac(6′)-Ib-cr, were located on an 86.9-kb IncFII-IncQ plasmid. The qnrB91 conferred greater fluoroquinolone resistance than qnrB2. SMKP03 aac(6′)-Ib-cr that possessed a gene mutation that resulted in an R102W substitution, namely, aac(6′)-Ib-D179Y, made a greater contribution to amikacin resistance than did aac(6′)-Ib-cr. SMKP03 harbored a nonsense mutation in mutS, which encodes a DNA repair enzyme. Introduction of this mutation into SMKP01 (SMKP01mutSA307T) resulted in a dramatic increase (>58-fold) in the frequency of spontaneous amikacin-resistant mutants relative to SMKP01, and the substantial mutants possessed aac(6′)-Ib-D179Y. SMKP01mutSA307T exhibited an unstable MIC for colistin (0.5 to 8 mg/liter). The results demonstrate that a disruptive mutation in MutS, arising during the clinical course of an infection, created a platform for the acquisition of amikacin nonsusceptibility and colistin heteroresistance in multidrug-resistant K. pneumoniae, mediated by the elevated frequency of spontaneous mutations.

In 2015, an estimated 17-year-old female Bornean elephant (Elephas maximus borneensis) at Fukuyama Zoo in Japan exhibited anorexia and significant weight loss. Pan-susceptible Mycobacterium tuberculosis complex (MTBC) was isolated from vaginal discharge, oral mucus, urine, and fecal samples by culture. The isolate was identified as Mycobacterium caprae by genetic analysis. Isoniazid, pyrazinamide, and levofloxacin were administered rectally. Body weight increased to normal, but subsequently decreased again. Elevation of liver enzymes occurred, likely related to the increase in isoniazid dosage. After recovery from side effects, the elephant's weight increased further. However, isoniazid-resistant M. caprae was isolated from oral mucus after anti-tuberculosis drug treatment for 9 mo. The regimen was changed to rifampicin, pyrazinamide, ethambutol, and levofloxacin, administered orally or rectally. The 18-mo treatment was completed in October 2018. This elephant has shown no clinical sign since. No MTBC-positive sample had been obtained as of March 2020.

Amikacin and colistin are effective against carbapenem-resistant Klebsiella pneumoniae. In 2017, we successively isolated three carbapenem-resistant K. pneumoniae isolates (ST967) from a patient with chronic renal failure in Japan. The first (SMKP01, sputum, day 0) and second (SMKP02, blood, day 14) strains were resistant to most antimicrobials tested but still susceptible to amikacin (MICs of 4 and 0.5 mg/liter, respectively) and colistin (MIC of 0.5 mg/liter for both). The third strain (SMKP03, blood, day 51) was not susceptible to amikacin (MIC, 32 mg/liter), and its MIC for colistin varied (0.5 to 8 mg/liter). Whole-genome sequencing of SMKP01 revealed that 17 of 20 antimicrobial resistance genes, including qnrB91 (a novel qnrB2 variant) and aac(6′)-Ib-cr, were located on an 86.9-kb IncFII-IncQ plasmid. The qnrB91 conferred greater fluoroquinolone resistance than qnrB2. SMKP03 aac(6′)-Ib-cr that possessed a gene mutation that resulted in an R102W substitution, namely, aac(6′)-Ib-D179Y, made a greater contribution to amikacin resistance than did aac(6′)-Ib-cr. SMKP03 harbored a nonsense mutation in mutS, which encodes a DNA repair enzyme. Introduction of this mutation into SMKP01 (SMKP01mutSA307T) resulted in a dramatic increase (>58-fold) in the frequency of spontaneous amikacin-resistant mutants relative to SMKP01, and the substantial mutants possessed aac(6′)-Ib-D179Y. SMKP01mutSA307T exhibited an unstable MIC for colistin (0.5 to 8 mg/liter). The results demonstrate that a disruptive mutation in MutS, arising during the clinical course of an infection, created a platform for the acquisition of amikacin nonsusceptibility and colistin heteroresistance in multidrug-resistant K. pneumoniae, mediated by the elevated frequency of spontaneous mutations. IMPORTANCE The emergence of multidrug resistance in pathogens such as Klebsiella pneumoniae is of great clinical concern. Antimicrobial resistance sometimes arises during the course of an infection. Although many studies have reported the emergence of antimicrobial resistance and novel antimicrobial resistance genes in the clinical isolates, the identity of the bacterial factor(s) that generate this emergence is still unclear. We report that a disruptive mutation in MutS, arising during the clinical course of an infection, created a context for the acquisition of colistin resistance and the emergence of a novel variant of the amikacin resistance gene in multidrug-resistant K. pneumoniae via an increase in the frequency of spontaneous mutation. This observation is important for understanding how K. pneumoniae develops multidrug resistance during infection and could potentially lead to new antimicrobial treatments for high-risk pathological microbes.

Background: Tibetan highlanders have adapted to hypoxic environments through the development of unique mechanisms that suppress an increase in hemoglobin (Hb) concentration even in high-altitude areas. Hb concentrations generally decrease with increasing age. However, in the highlands, chronic altitude sickness is known to occur in the elderly population. To investigate how aging in a hypoxic environment affects Hb levels in Tibetan highlanders, we focused on the Mustang people, who live above 3500 m. We tried to clarify the pure relationship between aging and Hb levels in a hypoxic environment.Results: We found that the Hb concentration increased with increasing age in females but not in males. Multivariate analysis showed that age, pulse pressure, the poverty index, and vascular diameter were strongly correlated with the Hb concentration. Conclusions: We found unique Hb dynamics among female Tibetan highlanders. As seen in these Hb dynamics, there may be sex-based differences in the adaptive mechanism in Tibetan highlanders., Tropical Medicine and Health, 49(1), art.no.2; 2020

Nontuberculous mycobacteria (NTM) are opportunistic pathogens of humans and animals and are transmitted among the environment, wildlife, livestock, and humans. The aim of this study was to investigate the rate of isolation and antimicrobial susceptibility of NTM in wildlife. In total, 178 samples of feces (n=131) and tissues (n=47) were collected from 11 wildlife species in Gifu Prefecture and Mie Prefecture, Japan, between June 2016 and October 2018. We isolated NTM from 15.3% (20/ 131) of fecal samples using Ogawa medium, and isolates were identified by sequencing the rpoB and hsp65 genes. The rpoB sequences were compared with those from other strains of human and environmental origin. The NTM isolates were obtained from sika deer (Cervus nippon), wild boar (Sus scrofa), Japanese monkey (Macaca fuscata), raccoon dog (Nyctereutes procyonoides), masked palm civet (Paguma larvata), and Japanese weasel (Mustela itatsi) and were classified as rapidly growing mycobacteria (RGM) and slowly growing mycobacteria (SGM). The 12 RGM identified were Mycolicibacterium peregrinum (n=5), Mycolicibacterium fortuitum (n=3), Mycolicibacterium septicum (n=3), and Mycolicibacterium thermoresistibile (n=1), and the eight SGM were Mycobacterium paraense (n=4), Mycolicibacter arupensis (n=2), Mycolicibacter virginiensis (n=1), and Mycobacterium nebraskense (n=1). The NTM from wildlife showed ≥99% similarity with strains from different sources including humans. The RGM were susceptible to the antimicrobial agents tested except for M. fortuitum, which was resistant to azithromycin and clarithromycin. The SGM showed multiple drug resistance qualities but were susceptible to amikacin, clarithromycin, and rifabutin. These results indicate that wildlife may be reservoir hosts of NTM in Japan. The presence of antimicrobial-resistant NTM in wildlife suggests that the trends of NTM antimicrobial susceptibility in wildlife should be monitored.

研究グループは、携帯電話の位置情報を用いて東京におけるコロナ禍の外出自粛や緊急事態宣言の効果を検証しました。本手法は、携帯電話の位置情報(GPS情報)から取得される大量の移動軌跡を解析することで、都市において人々がいつ、どこで、どの程度接触しているかを定量化できるものです。解析の結果、緊急事態宣言が発令される前の3月初週時点で人々の自宅外での接触率は平時の6割程度に減少し、緊急事態宣言を発令したことで、4月中旬での接触率は平時の2割程度まで抑えられていたことが示されました。さらには、接触の減少率とCOVID-19の実効再生産数との非線形な関係性も明らかにされ、今後さらなる感染拡大も予想される中、どの程度人々の接触を抑制するべきかについての定量的なエビデンスが示されました。, While large scale mobility data has become a popular tool to monitor the mobility patterns during the COVID-19 pandemic, the impacts of non-compulsory measures in Tokyo, Japan on human mobility patterns has been under-studied. Here, we analyze the temporal changes in human mobility behavior, social contact rates, and their correlations with the transmissibility of COVID-19, using mobility data collected from more than 200K anonymized mobile phone users in Tokyo. The analysis concludes that by April 15th (1week into state of emergency), human mobility behavior decreased by around 50%, resulting in a 70% reduction of social contacts in Tokyo, showing the strong relationships with non-compulsory measures. Furthermore, the reduction in data-driven human mobility metrics showed correlation with the decrease in estimated effective reproduction number of COVID-19 in Tokyo. Such empirical insights could inform policy makers on deciding sufficient levels of mobility reduction to contain the disease.

A multi-agent based averaging consensus algorithm is investigated over noisy undirected connected graphs. It is assumed that each agent can know measurements of the neighbors' state with bounded errors. A rigorous stopping rule which reveals an explicit relation between the number of iterations and the closeness of the agreement with a probabilistic guarantee is established based on a matrix Bernstein inequality. The result is illustrated through a numerical example.

In 2016, disseminated tuberculosis caused by Mycobacterium caprae was diagnosed in a captive Borneo elephant in Japan. The bacterium was initially identified from clinical isolates. An isolate collected during a relapse showed isoniazid monoresistance and a codon 315 katG mutation., Emerging Infectious Diseases, 24(10), pp.1937-1940; 2018

Background Two false-positive tuberculosis (TB) cases in Yamagata Prefecture, Japan, 2016. Objective To report the effectiveness of comparative genomics of Mycobacterium tuberculosis for identification of cross-contamination cases. Design Case report of laboratory cross-contamination. Results Beginning with detection of an identical genotype in two M. tuberculosis strains using variable number of tandem repeat typing, we suspected M. tuberculosis cross-contamination of specimens collected in a mycobacteriology laboratory based on epidemiological investigations. This suspicion was confirmed using comparative genomics of the two M. tuberculosis strains and a strain from an epidemiologically unrelated specimen from the same batch as the two strains in the mycobacteriology laboratory. All strains had an identical genomic sequence with no single nucleotide variants. Conclusion Comparative genomics, which offers the highest discrimination power, is a potent tool for identifying laboratory cross-contamination using epidemiological investigations.

BACKGROUND: Epidemiology of noncommunicable diseases (NCDs) such as obesity and diabetes mellitus (DM) are influenced by multiple hosts and environmental factors. This study aims to investigate the prevalence of NCDs and determine their risk factors among the adults residing in an isolated village situated at a rural highland of Nepal. METHODS: A cross-sectional survey was conducted in a village located at 3570 m. Each 188 randomly selected participants of age???18 years old answered a questionnaire and took a full physical exam that included biomedical measurements of glycosylated hemoglobin (HbA1c). RESULTS: The prevalence of intermediate hyperglycemia and DM was 31.6% and 4.6% respectively, and the prevalence of hypoxemia (SpO2 90%) was 27.1%. A multiple logistic regression analysis for factors for the prevalence of glucose intolerance (HbA1c ??6%) revealed older age (odds ratio [OR] 1.11, 95% confidence interval [CI] 1.06-1.16, for every 1 year increase) and SpO2 (OR for hypoxemia 3.58, 95% CI 1.20-10.68, vs SpO2 ??90%). CONCLUSIONS: Tibetan highlanders in the remote mountainous Mustang valley of Nepal have high prevalence of impaired glucose metabolism which could be related to hypoxemia imposed by the hypoxic conditions of high altitude living., Journal of physiological anthropology, 37(1), 20; 2018

This paper presents a bounded confidence gossip algorithm for describing the process of opinion formation over a communication network. Each agent in the network keeps a time-varying opinion vector (or state), which represents its opinion about a set of matters. A common confidence threshold is set for all of the agents. The states of agents in the network will be updated time by time according to an iterative procedure: At each time, 1) one agent is chosen randomly, then it chooses one of its neighbors on the communication graph to contact with; 2) they exchange their states; and 3) if they have different states and the distance between their states is strictly smaller than the confidence threshold, they update their states as the average of the two. This algorithm converges almost surely to some equilibrium point such that any two adjacent agents either have the same state or have distinct states whose distance is no less than the confidence threshold. This is called the constant confidence threshold algorithm. An increasing confidence threshold algorithm, which repeats the constant confidence threshold algorithm several times with increasing confidence threshold, is also proposed. The algorithm is also convergent almost surely to some equilibrium point. Applicability of the method to clustering problems is shown through numerical examples.

We identified a waterborne pseudo-outbreak of Mycobacterium chimaera in our stem cell transplantation center, which likely resulted from biofilm on the aerators of the handwashing machines in each patient’s room. Regular replacement of faucet parts can prevent biofilm formation and pseudo-outbreaks of M. chimaera through aerators.

Synchronous and asynchronous algorithms are presented for distributed minimax optimization. The objective here is to realize the minimization of the maximum of component functions over the standard...

A distributed optimization for a multi-agent system connected by a directed unbalanced random network is considered. It is shown that a sequense of candidate solutions of the standard algorithm for distributed optimization converges to a Pareto optimal solution of a multi-objective optimization which is to minimize objective functions of agents in a mean square sense. This is illustrated through a numerical example.

An asynchronous gossip algorithm with a restart strategy is proposed to an approximated distributed minimax optimization in this paper. The restart strategy controls a step length of a subgradient method and resets a local clock under a certain criteria in the algorithm. The convergence property is analyzed for the algorithm with the restart strategy. Numerical examples illustrate that the proposed algorithm works well in various instances and high approximation ratios.

A chance constrained AC optimal power flow is to find the optimal economic operation plan whose probability satisfying AC power flow equations and various inequality constraints on operating limits...