Retrospective identification of pathogenic mycobacterial species in fish: Mycobacterium pseudoshottsii YM-3, isolated from a yellowtail fish in 1986 in Kochi, Japan

The complete genome sequence of mycobacterial strain YM-3, isolated from cultured yellowtail in 1986, was determined. The strain was Mycobacterium pseudoshottsii, a closely related subspecies of Mycobacterium marinum, so the strain was isolated earlier than the first report of the subspecies in 2005.

Time-, spin-, and angle-resolved photoemission spectroscopy with a 1-MHz 10.7-eV pulse laser

We describe a setup of time-, spin-, and angle-resolved photoemission spectroscopy (tr-SARPES) employing a 10.7 eV (λ = 115.6 nm) pulse laser at a 1 MHz repetition rate as a probe photon source. This equipment effectively combines the technologies of a high-power Yb:fiber laser, ultraviolet-driven harmonic generation in Xe gas, and a SARPES apparatus equipped with very-low-energy-electron-diffraction spin detectors. A high repetition rate (1 MHz) of the probe laser allows experiments with the photoemission space-charge effects significantly reduced, despite a high flux of 1013 photons/s on the sample. The relatively high photon energy (10.7 eV) also brings the capability of observing a wide momentum range that covers the entire Brillouin zone of many materials while ensuring high momentum resolution. The experimental setup overcomes the low efficiency of spin-resolved measurements, which gets even more severe for the pump-probed unoccupied states, and affords the opportunity to investigate ultrafast electron and spin dynamics of modern quantum materials with energy and time resolutions of 25 meV and 360 fs, respectively.

Molecular Characterization of Mutations in Isoniazid- and Rifampicin-Resistant Mycobacterium tuberculosis Isolated in Thailand

The control of drug-resistant tuberculosis (TB) is a major challenge. The frequency and mutation characteristics indicate the efficiency of molecular tests for the rapid detection of TB drug resistance. This study examined the existence of katG and inhA mutations for isoniazid (INH) resistance and rpoB mutations for rifampicin (RFP) resistance. In total, 178 drug-resistant Mycobacterium tuberculosis (MTB) isolates were analyzed. Mutations in katG encoding and inhA regulatory regions were detected in 136/168 (81.0%) and 29/168 (17.3%), respectively, with the most prominent mutation of Ser315Thr substitution in katG in 126/168 (75.0%), and -15 C to T substitution in the regulatory region of the inhA (26/168; 15.5%). Two distinct katG mutations (Tyr337Cys, 1003InsG) were identified. Of 125 RFP-resistant isolates, 118 (94.4%) carried mutations affecting the 81-bp RFP resistance-determining region, with the most commonly affected codons 450, 445, and 435 identified in 74 (59.2%), 26 (20.8%), and 12 (9.6%) isolates, respectively. Genetic mutations were highly associated with phenotypic INH and RFP resistance, and the majority shared similarities with those reported in previous studies in Thailand and other Asian countries. These data are useful for guiding the use and improvement of molecular tests for TB drug resistance.

Citizen seismology helps decipher the 2021 Haiti earthquake

The August 14, Mw7.2, Nippes earthquake in Haiti occurred within the same fault zone as its devastating, Mw7.0, 2010 predecessor but struck the country when field access was limited by insecurity and conventional seismometers from the national network were inoperative. A network of citizen seismometers installed in 2019 provided near-field data critical to rapidly understand the mechanism of the mainshock and monitor its aftershock sequence. Their real-time data define two aftershock clusters that coincide with two areas of coseismic slip derived from inversions of conventional seismological and geodetic data. Machine learning applied to data from the citizen seismometer closest to the mainshock allows us to forecast aftershocks as accurately as with the network-derived catalog. This shows the utility of citizen science contributing to the understanding of a major earthquake.

Clonal/subclonal changes and accumulation of CTX-M-type β-lactamase genes in fluoroquinolone-resistant Escherichia coli ST131 and ST1193 strains isolated during the past 12 years, Japan

OBJECTIVES

Fluoroquinolone (FQ)- and third-generation cephalosporin-resistant Escherichia coli are increasing in Japan. In the early 2000s, the FQ-resistant E. coli clone ST131 increased in clinical settings worldwide. It frequently produces extended-spectrum β-lactamases (ESBLs) such as CTX-M. This study aimed to explore the characteristics of FQ-resistant E. coli isolated in Japan during 2008-2009 and 2020.

METHODS

We compared FQ-resistant E. coli clinical isolates from urine samples collected in 2020 (151 isolates) with a FQ-resistant E. coli collection isolated in 2008-2009 (42 isolates). Identification of E. coli ST131 clades and bla_CTX-M were determined by multiplex PCR. Sequence types of non-ST131 isolates were determined by whole-genome sequencing.

RESULTS

Although the prevalence of ST131 was comparable in 2020 (74.2%) and 2008-2009 (78.6%), the subclades differed during the two time periods (C1-nM27: 40.2% in 2008-2009 vs. 78.8% in 2020; C1-M27: 32.1% in 2008-2009 vs. 9.1% in 2020). The incidence of bla_CTX-M among ST131 isolates increased from 27.3% in 2008-2009 to 64.3% in 2020. bla_CTX-M was found in 80.6% and 93.8% of C1-M27 and C2 in 2020, respectively, and bla_CTX-M possession in C1-nM27 increased from 19.2% in 2008-2009 to 40% in 2020. FQ-resistant ST1193 was detected only in 2020 (17.9% of 151 isolates, of which 14.8% possessed bla_CTX-M).

CONCLUSION

Increased resistance of E. coli to FQs and third-generation cephalosporins in Japan can be attributed to the accumulation of bla_CTX-M in C1-nM27 and the increase of C1-M27 and C2 clades with high bla_CTX-M possession, alongside the spread of ST1193.

ERRATUM: Rapid and Simple Detection of Isoniazid-Resistant Mycobacterium tuberculosis Utilizing a DNA Chromatography-Based Technique

Volume 74, no.3, p.214-219, 2021. Page 214, affiliation "¹TBA Co., LTD, Sendai; ²Hokkaido University Research Center for Zoonosis Control, Sapporo; ³Hokkaido University, GI-CoRE Global Station for Zoonosis Control, Sapporo; ⁴Zambia National Public Health Institute, Ministry of Health, Lusaka, Zambia; ⁵Department of Pathology and Microbiology, University Teaching Hospital Ministry of Health, Lusaka, Zambia; and ⁶Ministry of Health, Ndeke House, Lusaka, Zambia." should read "¹TBA Co., LTD, Sendai, Japan; ²Hokkaido University Research Center for Zoonosis Control, Sapporo, Japan; ³Hokkaido University, GI-CoRE Global Station for Zoonosis Control, Sapporo, Japan; ⁴Zambia National Public Health Institute, Ministry of Health, Lusaka, Zambia; ⁵Department of Pathology and Microbiology, University Teaching Hospital Ministry of Health, Lusaka, Zambia; and ⁶Ministry of Health, Ndeke House, Lusaka, Zambia".

Drug-resistant Mycobacterium tuberculosis and its genotypes isolated from an outbreak in western Thailand

BACKGROUND

Multidrug-resistant TB (MDR-TB) outbreaks have occurred in the Thamaka district, Kanchanaburi province in Thailand.

METHODS

Seventy-two isolates, which included 7% mono-, 30.6% MDR and extensively drug-resistant TB (XDR-TB), were genotyped by spoligotyping, mycobacterial interspersed repetitive unit-variable-number tandem repeat (MIRU-VNTR) and single nucleotide polymorphism genotyping, and their drug resistance was analysed.

RESULTS

The spoligotyping results showed that Beijing spoligo-international type (SIT)1 was predominant (n=38; 52.8%) while the remaining were non-Beijing sublineages (n=34). The MIRU-VNTR analysis showed that Beijing isolates, most of which belonged to the modern type (n=37), formed 5 clusters and 13 individual patterns. In katG, only mutation Ser315Thr was identified. In rpoB, Ser531Leu was predominant, except for His526Arg and Leu533Pro, which were found in two isolates. A cluster of 14 Beijing strains contained these common mutations and shared the MIRU-VNTR genotype with isolates in the Thamaka district that had spread previously. Two U SIT523 isolates contained the mutations A1400G in rrs and Asp94Gly in gyrA genes, indicating a spread of XDR-TB.

CONCLUSIONS

Most mutations were associated with drug resistance and the specific MDR Beijing and XDR-TB in U SIT523 isolates remain. This genotyping is a key tool for tracking TB transmission in the Thamaka district of Thailand.

Evaluation of IS1245 LAMP in Mycobacterium avium and the influence of host-related genetic diversity on its application

Early detection and treatment are paramount for the timely control of Mycobacterium avium infections. Herein, we designed a LAMP assay targeting a widely used species-specific marker IS1245 for the rapid detection of M. avium and evaluated its applicability using human (n = 137) and pig (n = 91) M. avium isolates from Japan. The developed assay could detect as low as 1 genome copy of M. avium DNA within 30 minutes. All 91 (100%) M. avium isolates from pigs were detected positive while all other tested bacterial species were negative. Interestingly, among the 137 clinical M. avium isolates, 41 (30%) were undetectable with this LAMP assay as they lacked IS1245, the absence of which was revealed by PCR and whole-genome sequencing. These findings highlighted genotypic differences in M. avium strains from humans and pigs in Japan and how this diversity can influence the applicability of a detection tool across different geographic areas and hosts.

Emergence of vancomycin- and teicoplanin-resistant Enterococcus faecium via vanD5-harbouring large genomic island

BACKGROUND

Treatment of VRE is of clinical concern. While certain numbers of vanD-type VRE have been isolated, only two vanD5-harbouring Enterococcus faecium isolates have been reported in Canada and Japan.

METHODS

We report the isolation of vanD5-type E. faecium and the first ever determination of the whole-genome sequence to investigate the possible mechanisms of the acquisition of the vanD5 gene cluster in E. faecium.

RESULTS

Two vanD5-harbouring vancomycin-resistant E. faecium were isolated from the skin (SMVRE19) and faeces (SMVRE20) of a patient with a skin ulcer in Japan. The isolates exhibited vancomycin and teicoplanin MIC values of 128 mg/L, whilst the previous isolates of vanD5-harbouring E. faecium were only resistant to vancomycin. SMVRE19 and SMVRE20 were clones related to ST18, which is also seen in vanA- and vanB-type VRE. These isolates harboured an insertion element, ISEfm1, in the ddl gene, similar to a previously described teicoplanin-resistant vanD3-type E. faecium. The vanD5 gene cluster was integrated into the SMVRE20 chromosome as a part of a large genomic island (approximately 127 kb), similar to other recently spreading vanD variants in the Netherlands. The genomic island shared the greatest similarity with a part of the Blautia coccoides genome sequence, except for the region surrounding the vanD gene cluster.

CONCLUSIONS

This study reports that emergence of vancomycin- and teicoplanin-resistant vanD5-type E. faecium occurred via acquisition of the vanD5 cluster and ISEfm1 insertion into ddl. Considering the genetic similarity between the various VRE strains, the current study should serve as a warning against the spread of vanD5-type VRE.

Extracellular DNA of slow growers of mycobacteria and its contribution to biofilm formation and drug tolerance

DNA is basically an intracellular molecule that stores genetic information and carries instructions for growth and reproduction in all cellular organisms. However, in some bacteria, DNA has additional roles outside the cells as extracellular DNA (eDNA), which is an essential component of biofilm formation and hence antibiotic tolerance. Mycobacteria include life-threating human pathogens, most of which are slow growers. However, little is known about the nature of pathogenic mycobacteria’s eDNA. Here we found that eDNA is present in slow-growing mycobacterial pathogens, such as Mycobacterium tuberculosis, M. intracellulare, and M. avium at exponential growth phase. In contrast, eDNA is little in all tested rapid-growing mycobacteria. The physiological impact of disrupted eDNA on slow-growing mycobacteria include reduced pellicle formation, floating biofilm, and enhanced susceptibility to isoniazid and amikacin. Isolation and sequencing of eDNA revealed that it is identical to the genomic DNA in M. tuberculosis and M. intracellulare. In contrast, accumulation of phage DNA in eDNA of M. avium, suggests that the DNA released differs among mycobacterial species. Our data show important functions of eDNA necessary for biofilm formation and drug tolerance in slow-growing mycobacteria.

Endometrial epithelial-mesenchymal transition (EMT) by menstruation-related inflammatory factors during hypoxia

Endometriosis is characterised by inflammation and fibrotic changes. Our previous study using a mouse model showed that proinflammatory factors present in peritoneal haemorrhage exacerbated inflammation in endometriosis-like grafts, at least in part through the activation of prostaglandin (PG) E2 receptor and protease-activated receptor (PAR). In addition, hypoxia is a well-known inducer of fibrosis that may be associated with epithelial-mesenchymal transition (EMT). However, the complex molecular interactions between hypoxia and proinflammatory menstruation-related factors, PGE2 and thrombin, a PAR1 agonist, on EMT in endometriosis have not been fully characterised. To explore the effects of hypoxia and proinflammatory factors on EMT-like changes in endometrial cells, we determined the effects of PGE2 and thrombin (P/T) on EMT marker expression and cell migration in three dimensional cultured human endometrial epithelial cells (EECs) and endometrial stromal cells (ESCs). Treatment of EECs with P/T under hypoxia stimulated cell migration, increased the expression of mesenchymal N-cadherin, vimentin and C-X-C chemokine receptor type 4 (CXCR4), and reduced the expression of epithelial E-cadherin. Furthermore, treatment with C-X-C motif chemokine ligand 12 (CXCL12), a ligand for CXCR4, increased EMT marker expression and cell migration. In ESCs, P/T or oestrogen treatment under hypoxic conditions increased the expression and secretion of CXCL12. Taken together, our data show that hypoxic and proinflammatory stimuli induce EMT, cell migration and inflammation in EECs, which was increased by CXCL12 derived from ESCs. These data imply that inflammatory mediators in retrograde menstrual fluid contribute to ectopic endometrial EMT and migration in the presence of peritoneal hypoxia.

Comparative genomic analysis of Mycobacterium intracellulare: implications for clinical taxonomic classification in pulmonary Mycobacterium avium-intracellulare complex disease

BACKGROUND

Mycobacterium intracellulare is a representative etiological agent of emerging pulmonary M. avium-intracellulare complex disease in the industrialized countries worldwide. The recent genome sequencing of clinical strains isolated from pulmonary M. avium-intracellulare complex disease has provided insight into the genomic characteristics of pathogenic mycobacteria, especially for M. avium; however, the genomic characteristics of M. intracellulare remain to be elucidated.

RESULTS

In this study, we performed comparative genomic analysis of 55 M. intracellulare and related strains such as M. paraintracellulare (MP), M. indicus pranii (MIP) and M. yonogonense. Based on the average nucleotide identity, the clinical M. intracellulare strains were phylogenetically grouped in two clusters: (1) the typical M. intracellulare (TMI) group, including ATCC13950 and virulent M.i.27 and M.i.198 that we previously reported, and (2) the MP-MIP group. The alignment of the genomic regions was mostly preserved between groups. Plasmids were identified between groups and subgroups, including a plasmid common among some strains of the M.i.27 subgroup. Several genomic regions including those encoding factors involved in lipid metabolism (e.g., fadE3, fadE33), transporters (e.g., mce3), and type VII secretion system (genes of ESX-2 system) were shown to be hypermutated in the clinical strains. M. intracellulare was shown to be pan-genomic at the species and subspecies levels. The mce genes were specific to particular subspecies, suggesting that these genes may be helpful in discriminating virulence phenotypes between subspecies.

CONCLUSIONS

Our data suggest that genomic diversity among M. intracellulare, M. paraintracellulare, M. indicus pranii and M. yonogonense remains at the subspecies or genovar levels and does not reach the species level. Genetic components such as mce genes revealed by the comparative genomic analysis could be the novel focus for further insight into the mechanism of human pathogenesis for M. intracellulare and related strains.

Prognostic value of hybrid cardiac perfusion SPECT/CT for patients with coronary artery disease after coronary artery bypass grafting

Introduction

Patients with coronary artery disease (CAD) undergoing coronary artery bypass grafting (CABG) occasionally experience recurrent myocardial ischemia. Because of their severe CAD and its complicated hemodynamics, conventional cardiac perfusion SPECT often cannot reveal the severity and prognosis solely. Hybrid cardiac SPECT/CT imaging simultaneously shows myocardial ischemia distribution, coronary artery lesion distribution, and their relationship, and this modality may enable detailed interpretation and risk stratification for such patients.

Aim

This study aimed to assess the prognostic value of hybrid cardiac SPECT/CT for patients with CAD and suspected myocardial ischemia after CABG.

Methods

A total of 201 consecutive patients, registered between April 2016 and September 2018, with suspected recurrent angina pectoris after CABG requiring examinations for myocardial ischemia were included in this study. Among these, 135 patients who underwent cardiac perfusion SPECT, cardiac CT, and hybrid cardiac SPECT/CT imaging were analyzed. In the SPECT-only analysis, SDS was calculated, and the patients were divided into none-to-mild (SDS <4) and moderate-to-severe ischemia (SDS ≥4) groups. In the SPECT/CT analysis, the patients were divided into a matched group (SPECT reversible accumulation defects [SDS ≥2] along coronary arteries with significant lesions) and an unmatched group (accumulation defects not coincided with coronary artery territories or no significant stenoses in the corresponding coronary arteries). All patients were observed from the time of these tests for the occurrence of major adverse cardiac events (MACE), and the prognostic performances of these analyses were compared.

Results

In the SPECT-only analysis, 62 were in the none-to-mild group and 73 were in the moderate-to-severe group. In the SPECT/CT analysis, 61 were in the matched group and 74 were in the unmatched group. Within the follow-up period of 29±8 months, 15 patients experienced MACE. The patients' prognoses were clearly stratified by hybrid SPECT/CT analysis (matched: 13/61, 21.3% vs. unmatched: 2/74, 2.7%) compared with SPECT-only analysis (moderate-to-severe: 11/73, 15.0% vs. none-to-mild: 4/62, 6.5%). The hybrid cardiac SPECT/CT analysis was more strongly associated with the occurrence of MACE compared with SPECT-only analysis (p=0.008 vs. p=0.04, respectively).

Conclusions

Hybrid cardiac SPECT/CT imaging can have higher prognostic value compared with stand-alone cardiac perfusion SPECT for patients with CAD after CABG.

Funding Acknowledgement

Type of funding source: None

Rapid and Simple Detection of Isoniazid-Resistant Mycobacterium tuberculosis Utilizing a DNA Chromatography-Based Technique

Despite the availability of anti-tuberculosis drugs, the treatment of tuberculosis has been complicated by drug-resistant tuberculosis. The early detection of drug resistance makes early treatment possible. However, the available tools are mainly for rifampicin resistance detection, and the existing isoniazid resistance detection method is expensive, highly technical, and complicated, making it unsustainable for use in developing nations. This study aimed to develop a simple, rapid, and low-cost diagnostic kit for isoniazid-resistant tuberculosis using the single-stranded tag hybridization method to target an isoniazid resistance-conferring mutation. Specificity and sensitivity were assessed using DNA extracted from 49 isoniazid-resistant and 41 isoniazid-susceptible Mycobacterium tuberculosis clinical isolates cultured in mycobacterial growth indicator tubes. Positive signals were observed on mutant and wild-type lines with 100% sensitivity and specificity compared with Sanger sequencing results. In contrast, no positive signal was observed for non-tuberculosis mycobacteria. The detection limit of this method was 10³ CFU or less. The STH-PAS system for isoniazid-resistant M. tuberculosis detection developed in this study offers a better alternative to conventional phenotypic isoniazid resistance determination, which will be of both clinical and epidemiological significance in resource-limited nations.

Elucidating the Structural Requirement of Uridylpeptide Antibiotics for Antibacterial Activity

The synthesis and biological evaluation of analogues of uridylpeptide antibiotics were described, and the molecular interaction between the 3'-hydroxy analogue of mureidomycin A (3'-hydroxymureidomycin A) and its target enzyme, phospho-MurNAc-pentapeptide transferase (MraY), was analyzed in detail. The structure-activity relationship (SAR) involving MraY inhibition suggests that the side chain at the urea-dipeptide moiety does not affect the MraY inhibition. However, the anti-Pseudomonas aeruginosa activity is in great contrast and the urea-dipeptide motif is a key contributor. It is also suggested that the nucleoside peptide permease NppA1A2BCD is responsible for the transport of 3'-hydroxymureidomycin A into the cytoplasm. A systematic SAR analysis of the urea-dipeptide moiety of 3'-hydroxymureidomycin A was further conducted and the antibacterial activity was determined. This study provides a guide for the rational design of analogues based on uridylpeptide antibiotics.

Sitafloxacin has a potent activity for eradication of extended spectrum β-lactamase-producing fluoroquinolone-resistant Escherichia coli forming intracellular bacterial communities in uroepithelial cells

INTRODUCTION

Eradication of asymptomatic bacteriuria (ASB) before urological procedures is important to reduce the risk for infectious complications after surgery. However, the appropriate regimen for antimicrobial treatment has not been fully determined. We experienced continuous (over 10 months) isolation of extended spectrum β-lactamase (ESBL)-producing fluoroquinolone-resistant Escherichia coli from urine of an asymptomatic patient. The four isolates obtained (SMESC1 to 4) were international high-risk clones of O25b:H4-ST131-H30R, and originated from one strain, as revealed by the whole genome sequences. Although the patient received meropenem (MEPM) and fosfomycin (FOM), to which the strains were susceptible before the urological procedures, they could not be eradicated.

METHODS

To explore the reason for the continuous isolation even after MEPM and FOM administration, antimicrobial killing of adherent and/or intracellular bacterial communities (IBC) formed by coculture of the E. coli cells and T24 bladder epithelial cells were examined.

RESULTS

FOM and levofloxacin did not decrease viable E. coli cells compared with gentamicin. MEPM partly decreased them, and sitafloxacin (STFX) decreased them most potently. These observations indicate that E. coli can survive in the urinary tract under antimicrobial administration, and some antimicrobials such as FOM and MEPM cannot eradicate E. coli in uroepithelial cells. Adhesion on urinary epithelial cells and/or IBC formation might result in continuous isolation from the urinary tract and recurrence of ASB and urinary tract infections.

CONCLUSIONS

The present study suggests that STFX is a promising optional agent for the eradication of ESBL-producing fluoroquinolone-resistant E. coli in the urinary tract before urological procedures.

Mutations in rpoB and katG genes and the inhA operon in multidrug-resistant Mycobacterium tuberculosis isolates from Zambia

OBJECTIVES

It is established that resistance to rifampicin (RIF) in 90% of RIF-resistant Mycobacterium tuberculosis isolates is attributable to point mutations in the rpoB gene, whilst 50-95% of M. tuberculosis resistance to isoniazid (INH) is caused by mutations in the katG gene. However, the patterns and frequencies of mutations vary by geographical region. In Zambia, the genetic mechanisms of resistance of M. tuberculosis to RIF and INH were unreported before this study.

METHODS

Using gene sequencing, the rpoB, katG and inhA genes of 99 multidrug-resistant M. tuberculosis (MDR-TB) and 49 pan-susceptible M. tuberculosis isolates stored at a tuberculosis reference laboratory from 2013 to 2016 were analysed and were compared with published profiles from other African countries.

RESULTS

Of the 99 MDR-TB isolates, 95 (96.0%) carried mutations in both rpoB and katG. No mutations were detected among the pan-susceptible isolates. The most common mutations among RIF- and INH-resistant isolates were in codon 531 of the rpoB gene (55.6%; 55/99) and codon 315 of the katG gene (94.9%; 94/99), respectively. Distinctly, katG mutations were predominantly high among Zambian isolates (96.0%) compared with other countries in the region.

CONCLUSION

Resistance-associated mutations to RIF and INH circulating in Zambia are similar to those reported globally, therefore these data validate the applicability of molecular diagnostic tools in Zambia. However, katG mutations were predominantly high among M. tuberculosis isolates in this study compared with other regional countries and might distinguish cross-boundary transmission of MDR-TB from other African nations.

Contribution of β-lactamase and efflux pump overproduction to tazobactam-piperacillin resistance in clinical isolates of Escherichia coli

INTRODUCTION

Tazobactam-piperacillin (TZP) is a mixture of a broad-spectrum penicillin and an irreversible β-lactamase inhibitor. TZP is effective against Gram-negative bacteria that produce extended-spectrum β-lactamases, and it is used as a first-line or second-line drug to treat serious infections.

METHODS

This study identified three TZP-resistant and two TZP-intermediate strains among 514 clinical isolates of Escherichia coli.

RESULTS

These five isolates possessed one or more β-lactamase genes, bla_TEM-1, bla_CTX-M-2, bla_CTX-M-14, and/or bla_CMY-8. The expression levels of β-lactamase genes and acrAB genes in the strains were examined by using real-time reverse transcription PCR. The total enzymatic piperacillin-degrading activity in cells was determined. Two TZP-resistance mechanisms were identified: hyperproduction of TEM-1 in the two resistant strains; and simultaneous high production of β-lactamase and efflux pump AcrAB in the two TZP-intermediate isolates. The latter are an international high-risk clone O25b:H4-ST131-H30R.

CONCLUSION

TZP resistance is still rare in clinical isolates of E. coli. However, resistance can develop on high production and/or combinations of known antimicrobial resistance mechanisms in different ways.

Direct detection of Mycobacterium tuberculosis in clinical samples by a dry methyl green loop-mediated isothermal amplification (LAMP) method

The purpose of this study was to develop a simple visual methyl green (MeG) based dry loop-mediated isothermal amplification (LAMP) method for early detection of Mycobacterium tuberculosis (MTB) from clinical samples. We identified MeG as an indicator of a positive LAMP reaction, where a positive reaction gave a blue-green color while a negative reaction was colorless. The MeG MTB-LAMP system was further simplified by drying all reagents for ease of use, and was then validated for its ability to diagnose TB directly using Nepalese clinical samples. We evaluated the dry MeG MTB-LAMP with 69 new TB suspected samples from patients that did not have a confirmed history of TB treatment and found the sensitivity in culture positive samples as 92.8% (13/14) and specificity in culture negative samples as 96.3% (53/55). Our LAMP system has the potential to be a point of care test for early diagnosis of active TB in developing countries.

[Role of Cancer Chemotherapy Is Expected to Improve PS and QOL]

We report three cases of advanced lung cancer with poor PS treated with molecular-targeted drugs and consider the role of cancer chemotherapy to improve quality of life(QOL). Case 1: A 67-year-old woman(PS 3)with multiple liver, bone, and lymph node metastases from lung cancer received gefitinib and radiation therapy for bone metastasis. Abdominal CT then showed shrinkage of the liver metastasis, and daily life activities became possible after 2 months. Case 2: A 76-year-old woman with SVC syndrome from Stage ⅢA of lung cancer received gefitinib and radiation therapy. After that, edema and cough disappeared, and the PS improved from 3 to 0. Case 3: A 41-year-old woman with pleural dissemination from Stage Ⅳ lung cancer received ALK inhibitors and anticancer drug therapy for 5 years. Subsequently, a decrease in QOL was noted due to symptoms such as bloody sputum and persistence of cough. ALK inhibitors were administered as a re-challenge. A dramatic improvement in symptoms was observed in a few days. Even if the general condition is poor, PS can be improved by administering drugs such as molecular-targeted drugs.

Evaluation of Susceptibilities to Carbapenems and Faropenem Against Cephalosporin-Resistant Neisseria gonorrhoeae Clinical Isolates with penA Mosaic Alleles

Neisseria gonorrhoeae is a principal pathogen for sexually transmitted infections, especially for male urethritis. Currently, the prevalence of multidrug resistance is increasing. Carbapenems are broad-spectrum antimicrobials that are widely used in the clinical setting, especially for multidrug-resistant Gram-negative bacteria. However, susceptibility to carbapenems has not been well evaluated for cephalosporin-resistant N. gonorrhoeae isolates. In this study, we determined the susceptibility to a series of carbapenems (meropenem, imipenem, doripenem, and biapenem) and faropenem against cephalosporin-resistant (resistant to cefixime, but susceptible to ceftriaxone) and cephalosporin-susceptible N. gonorrhoeae clinical isolates. The gene mutations associated with β-lactam resistance were evaluated. All cephalosporin-resistant N. gonorrhoeae isolates possessed mosaic mutation alleles in penA (NG-STAR penA-10.001, 27.001, or 108.001). They exhibited a low minimum inhibitory concentration (MIC) (≤0.125 mg/L) for meropenem and markedly high MICs (0.5-2 mg/L) for other carbapenems and faropenem. The strongest association was observed between the mosaic alleles in penA and decreased susceptibility to carbapenems and faropenem compared with mutations in mtrR, porB, and ponA. These results suggest that meropenem may serve as an alternative therapeutic agent for cephalosporin-resistant N. gonorrhoeae with a mosaic allele in penA, whereas other carbapenems and faropenem may be ineffective.

Multiclonal Expansion and High Prevalence of β-Lactamase-Negative Haemophilus influenzae with High-Level Ampicillin Resistance in Japan and Susceptibility to Quinolones

β-Lactam-resistant Haemophilus influenzae is a clinical concern. A high prevalence (>40%) of β-lactamase-negative high-level ampicillin-resistant H. influenzae (high-BLNAR) isolates in Japan has been reported. However, the reasons for the expansion are unknown. High-BLNAR strains possess an amino acid substitution, either Asn526Lys (group III) or Arg517His (group III-like) in addition to Ser385Thr, in penicillin-binding protein 3 (PBP3). To determine the current prevalence of high-BLNAR strains and the mechanisms behind their expansion in Japan, their prevalence, PBP3 types, multilocus sequence types, and susceptibilities to quinolones approved in Japan as alternatives were determined. Sixty percent of H. influenzae clinical isolates (62/104 isolates) were β-lactamase-negative ampicillin-resistant H. influenzae (BLNAR) strains. Among BLNAR isolates, 92% (57/62 isolates) were high-BLNAR strains. Most isolates were classified as belonging to group III, which contained many genotypes (11 PBP3 types and 25 sequence types). These results indicated that the expansion of high-BLNAR isolates was multiclonal and such strains are still predominant in Japanese clinical settings. One high-BLNAR isolate harbored the novel amino acid substitution Asn526Met in addition to Ser385Thr in PBP3, suggesting a new group (group IV). No quinolone-resistant H. influenzae isolates were identified. The MICs for the quinolones (moxifloxacin, garenoxacin, and tosufloxacin) were similar to that for levofloxacin, whereas sitafloxacin exhibited a lower MIC. However, we obtained 4 H. influenzae isolates with decreased quinolone susceptibility with the amino acid substitution Ser84Leu in GyrA, and 3 of those isolates were high-BLNAR isolates. In summary, this study shows that multiclonal high-BLNAR strains predominate in a Japanese university hospital. Isolates remain sensitive to quinolones, but vigilance is required to prevent the development of fluoroquinolone resistance in high-BLNAR strains.

Whole genome analysis of a multidrug-resistant Streptococcus pneumoniae isolate from a patient with invasive pneumococcal infection developing disseminated intravascular coagulation

Multidrug-resistant Streptococcus pneumoniae strains were isolated from blood and sputum of a patient with disseminated intravascular coagulation in Sapporo city, Japan. These antibiograms were only susceptible to vancomycin, linezolid, daptomycin, some carbapenems, and some fluoroquinolones. Identical antibiograms, serotypes (19F), and sequence types (ST10017) suggested a shared origin of these isolates. Only one ST10017 strain has been isolated in the same city in Japan previously (2014), and the 2014 isolate is still susceptible to macrolides. The whole genome of the blood-derived isolate was sequenced. The strain harbored resistance mutations in parC, gyrA, pbp1a, pbp2a, pbp2b, and pbp2x, and harbored the resistance genes, ermB and tetM. The nucleotide sequences of parC and pbp2x genes of strain MDRSPN001 were clearly different from those of other S. pneumoniae strains and were similar to those of oral streptococci strains. These findings suggest that strain MDRSPN001 has been rapidly and drastically evolving multidrug resistance by gene replacement and accumulation of genes originating from other strains, such as oral streptococci, Streptococcus mitis.

Tuberculosis Caused by Mycobacterium orygis in Dairy Cattle and Captured Monkeys in Bangladesh: a New Scenario of Tuberculosis in South Asia

Mycobacterium orygis, commonly known as the oryx bacillus and a newly proposed Mycobacterium tuberculosis complex subspecies, was isolated from 18 cattle in a dairy farm and two captured rhesus monkeys in a zoo in Bangladesh. All the infected animals had tuberculosis lesions in their lungs, suggesting transmission and infection with M. orygis by an airborne route. The 20 isolates were analysed using a range of conventional and molecular typing methods, and RD-deletion typing and sequencing of selected genes confirmed the isolates as M. orygis. Multiple-locus variable-number tandem repeat analysis (MLVA) allowed the isolates to be divided into three clusters based on the relatedness of their MLVA profiles. The two monkey isolates shared the same MLVA pattern with 15 of the cattle isolates, whereas the remaining three cattle isolates had different patterns, even though the latter animals had been kept in the same dairy farm. The diversity observed among isolates may suggest the bacteria have been established in this area for a long period. This study along with other recent findings that report the detection of M. orygis from animals as well as humans originating from South Asia potentially indicate endemic distribution of M. orygis in South Asia.

Hip fracture incidence in Japan: Estimates of new patients in 2012 and 25-year trends

We estimated the number of hip fracture patients in 2012 in Japan and investigated the trends in incidence during a 25-year period from 1987 to 2012. Despite the increasing number of patients, the incidence of hip fracture in both men and women aged 70-79 years showed the possibility of decline.

INTRODUCTION

The objectives of this study were to estimate the number of hip fracture patients in 2012, to investigate the trends in incidence during a 25-year period from 1987 to 2012, and to determine the regional differences in Japan.

METHODS

Data were collected through a nationwide survey based on hospitals by a mail-in survey. Hip fracture incidences by sex and age and standardized incidence ratios by region were calculated.

RESULTS

The estimated numbers of new hip fracture patients in 2012 were 175,700 in total (95 % CI 170,300-181,100), 37,600 (36,600-38,600) for men and 138,100 (134,300-141,900) for women. The incidence rates in both men and women aged 70-79 years were the lowest in the 20-year period from 1992 to 2012. The incidence was higher in western areas of Japan than that in eastern areas in both men and women; however, the difference in the incidence of hip fracture between western and eastern areas is becoming smaller.

CONCLUSIONS

Despite the increasing number of new patients, the incidence of hip fracture in both men and women aged 70-79 years showed the possibility of decline. The exact reasons for this are unknown, but various drugs for improving bone mineral density or preventing hip fracture might have influenced the results. A decrease in the differences in nutrient intake levels might explain some of the change in regional differences in Japan.

Randomized clinical trial: rikkunshito in the treatment of functional dyspepsia--a multicenter, double-blind, randomized, placebo-controlled study

BACKGROUND

Rikkunshito, a standardized Japanese herbal medicine, is thought to accelerate gastric emptying and relieve dyspepsia, although no large-scale, randomized, placebo-controlled trials of rikkunshito have been conducted. This study aimed to determine the efficacy and safety of rikkunshito for treating functional dyspepsia (FD).

METHODS

FD patients received 2.5 g rikkunshito or placebo three times a day for 8 weeks in this multicenter, randomized, placebo-controlled, parallel-group trial. The primary end point was the proportion of responders at 8 weeks after starting test drug, determined by global patient assessment (GPA). The improvement in four major dyspepsia symptoms severity scale was also evaluated. In addition, plasma ghrelin levels were investigated before and after treatment.

KEY RESULTS

Two hundred forty-seven patients were randomly assigned. In the eighth week, the rikkunshito group had more GPA responders (33.6%) than the placebo (23.8%), although this did not reach statistical significance (p = 0.09). Epigastric pain was significantly improved (p = 0.04) and postprandial fullness tended to improve (p = 0.06) in the rikkunshito group at week 8. Rikkunshito was relatively more effective among Helicobacter pylori-infected participants (rikkunshito: 40.0% vs placebo: 20.5%, p = 0.07), and seemed less effective among H. pylori-uninfected participants (rikkunshito: 29.3% vs placebo: 25.6%, p = 0.72). Among H. pylori-positive individuals, acyl ghrelin levels were improved just in rikkunshito group. There were no severe adverse events in both groups.

CONCLUSIONS & INFERENCES

Administration of rikkunshito for 8 weeks reduced dyspepsia, particularly symptoms of epigastric pain and postprandial fullness. (UMIN Clinical Trials Registry, Number UMIN000003954).

Development and fundamental evaluation of flexible viewpoint laparoscope using a oblique viewing laparoscope

We have developed a new type of laparoscope with flexible view point. This system can move the view without moving laparoscope itself. To achieve the wide range of view moving, we used a commercial 30° oblique-viewing laparoscope and special lens. The system control the view by rotating the oblique-viewing laparoscope and a sleeve which is attached to the special lens by motors independently. From the evaluation experiments, we confirmed the laparoscope which has 70° view angle could move the view ±60°. In the image quality evaluation experiment, degradation of the image quality was small. The positioning accuracy was 2.4±1.7 mm repeatability was 0.48 mm which lead to precise view control. The system achieve the safe and smooth manipulation of the laparoscopic view.

p.E66Q mutation in the GLA gene is associated with a high risk of cerebral small-vessel occlusion in elderly Japanese males

BACKGROUND AND PURPOSE

GLA is the causative gene of Fabry disease, an X-linked lysosomal storage disorder resulting from α-galactosidase A (α-GAL) deficiency. Stroke is an important manifestation of Fabry disease, and recent epidemiological studies have indicated that up to 4.9% of young male cryptogenic stroke patients have GLA mutations. To determine the importance of GLA mutations in the general stroke population, the frequency of GLA mutations in Japanese male ischaemic stroke (IS) patients with various risk factors and ages was measured.

METHODS

A total of 475 male IS patients (mean age 69.7 ± 12.5 years), were enrolled in this study. A blood sample was obtained to produce blood spots for measurement of α-GAL activity. Blood samples with decreased enzymatic activity were reassayed and the entire GLA gene was analyzed by direct DNA sequencing if α-Gal A activity was consistently low.

RESULTS

α-Gal A activity was decreased in 10 men, five of whom (1.1%) had the GLA gene mutation, p.E66Q. All IS patients with p.E66Q mutation had substantial residual α-Gal A activity, in contrast to patients with classic-type Fabry disease. Clinically, all patients with p.E66Q mutation were > 50 years old and had multiple small-vessel occlusions (lacunar infarctions). Statistical analysis using Fisher's exact test showed the allele frequency of GLA p.E66Q in patients with small-vessel occlusion to be significantly higher than that in the general Japanese population [odds ratio (OR) = 3.34, P = 0.025).

CONCLUSIONS

GLA p.E66Q mutation is a genetic risk factor for cerebral small-vessel occlusion in elderly Japanese males.

New automatic cell isolation system for flow cytometry: cell isolation unit and staining reagent kit

Flow cytometry is well-known cell analysis method and useful to gain quantitative information from cells in blood, however, it is not widely used for solid tissues in clinical settings. This is partly because it takes a long time to prepare samples and the operation can be complicated. To resolve these problems, we developed a new automatic cell isolation system which consists of cell isolation unit and staining reagent kit specialized for flow cytometry. With this new system, cell isolation can be done more rapidly and easily. By using this method, we could determine optimum condition to disintegrate porcine colon tissue and stain cells stably in 6 minutes. This result indicates that our method can provide analysis data within 10 minutes. We also evaluated our method in colorectal cancer patients, and the result was promising. All the data suggests that this method can support and facilitate rapid diagnosis.

Mycobacterium bovis infection at the interface between domestic and wild animals in Zambia

BACKGROUND

In Zambia, the presence of bovine tuberculosis in both wild and domestic animals has long been acknowledged and mutual transmission between them has been predicted without any direct evidence. Elucidation of the circulating Mycobacterium bovis strains at wild and domestic animals interphase area in Zambia, where bovine tuberculosis was diagnosed in wildlife seemed to be important.

RESULTS

A PCR identified 15 and 37 M. bovis isolates from lechwe and cattle, respectively. Spoligotype analysis revealed that M. bovis strains from lechwe and cattle in Kafue basin clustered into a major node SB0120, where isolates outside the Kafue basin clustered into different nodes of SB0131 and SB0948. The comparatively higher variety of strains in cattle compared to lechwe elucidated by Mycobacterial Interspersed Repetitive Units-Variable Number Tandem Repeats analyses are consistent with cattle being the probable source of M. bovis in wild and domestic animals interphase area in Zambia.

CONCLUSIONS

These results provide strong evidence of M. bovis strains transfer between cattle and lechwe, with the latter having developed into a sylvatic reservoir host.

Immunohistochemical detection of CDKN2, retinoblastoma and p53 gene products in primary astrocytic tumors

The expressions of p16(INK4), retinoblastoma (RB) and p53 protein were immunohistochemically examined in 70 primary astrocytic tumors. In 58 patients with high grade astrocytoma (18 anaplastic astrocytomas and 40 glioblastomas), 30 (51.1%) and 15 (25.9%) cases were undetectable for p16(INK4) and pRB, respectively, but their lack occurred infrequently in 12 low grade astrocytomas. The expression of p16(INK4) was inversely correlated with that of PRB, especially in glioblastomas. Accumulation of p53 was detected in 32 (45.7%) of 70 cases without any dependence on the grade. A deregulation of three tumor suppressor gene products most often occurs singly. Only patients with negative staining for pRB were significantly associated with a shorter survival time. Our findings suggest that loss of functional pRB at the G1/S check point may represent an important step in glioblastoma development and have a stronger negative impact on clinical outcome than p16(INK4) or p53 aberrations.

A rapid loop-mediated isothermal amplification assay targeting hspX for the detection of Mycobacterium tuberculosis complex

A rapid, simple, and low-cost diagnostic tool for tuberculosis (TB) detection is urgently needed in countries with a high TB burden. Here, we report a novel loop-mediated isothermal amplification (LAMP) assay targeting the hspX gene for the rapid detection of Mycobacterium tuberculosis, M. bovis, M. africanum, and M. microti. The specificity of this assay was evaluated using 4 reference strains of Mycobacterium tuberculosis complex (MTC), 22 species of non-tuberculous mycobacteria (NTM), 7 non-mycobacterial species, and 50 clinical M. tuberculosis isolates. All the reference MTC strains and M. tuberculosis clinical isolates were successfully detected by this method, and there were no false-positive results with NTM or non-mycobacterial species, which demonstrates the high specificity of this assay for MTC. The detection limit was 10 copies of MTC genome within 27 min, and the detection speed of this assay was higher than that of any other isothermal methods reported so far. Because of its speed, simplicity, sensitivity, specificity, and inexpensiveness, the TB hspX LAMP assay is a potential gene diagnostic method for TB detection in developing countries with a high TB burden.

High frequency of overlap between functional dyspepsia and overactive bladder

BACKGROUND

Overactive bladder syndrome (OAB) is defined as a symptom complex comprising urgency, with or without urge incontinence, and usually frequency and nocturia. The association between irritable bowel syndrome (IBS) and bladder symptoms has been reported. This study is designed to investigate whether functional dyspepsia (FD), like IBS, is associated with OAB.

METHODS

A web surveys containing questions about OAB, FD, IBS, and demographics were completed by 5494 public individuals (2302 men and 3192 women) who have no history of severe illness. The prevalence and overlap of OAB, FD, and IBS were examined.

KEY RESULTS

Among participants with FD, 20.5% could also be diagnosed with OAB (odds ratio [OR]: 2.85; 95% confidence interval [CI]: 2.21-3.67). Although concomitant FD and IBS were more strongly associated with OAB (OR: 4.34; 95% CI: 2.81-6.73), OAB was also highly prevalent among participants with FD but without IBS (OR: 3.09; 95% CI: 2.29-4.18). Among participants with FD, an overlapping OAB condition was more prevalent in those with both postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS) (OR: 3.75; 95% CI: 2.48-5.67) than in those with PDS or EPS alone. Among participants with OAB, the severity of bladder symptoms was greater in participants with dyspeptic symptoms than without them.

CONCLUSIONS & INFERENCES

Overactive bladder syndrome is common among FD patients, even if they do not have IBS. To improve FD patients' quality of life, it will be important to provide management for OAB.

Enhanced translational diffusion of confined water under electric field

High resolution quasielastic neutron scattering measurements have been used to study the effects of applied electric field on the dynamics of water molecules confined in the pores of folded silica sheet material FSM-12 with an average pore diameter (apd) of 16 Å. In the absence of field, there is a significant slowing down of the water molecule diffusion as the temperature is lowered, in agreement with previous observations. The application of a moderate electric field of 2.5 kV/mm remarkably enhances the translational diffusion of water molecules. We interpret this as being due to a disruption of the hydrogen bonding by the electric field. This new observation suggests that existing theories valid at large electric field strengths may have to be corrected at moderate fields.

Exome sequencing in a family with an X-linked lethal malformation syndrome: clinical consequences of hemizygous truncating OFD1 mutations in male patients

Oral-facial-digital syndrome type 1 (OFD1; OMIM #311200) is an X-linked dominant disorder, caused by heterozygous mutations in the OFD1 gene and characterized by facial anomalies, abnormalities in oral tissues, digits, brain, and kidney; and male lethality in the first or second trimester pregnancy. We encountered a family with three affected male neonates having an 'unclassified' X-linked lethal congenital malformation syndrome. Exome sequencing of entire transcripts of the whole X chromosome has identified a novel splicing mutation (c.2388+1G > C) in intron 17 of OFD1, resulting in a premature stop codon at amino acid position 796. The affected males manifested severe multisystem complications in addition to the cardinal features of OFD1 and the carrier female showed only subtle features of OFD1. The present patients and the previously reported male patients from four families (clinical OFD1; Simpson-Golabi-Behmel syndrome, type 2 with an OFD1 mutation; Joubert syndrome-10 with OFD1 mutations) would belong to a single syndrome spectrum caused by truncating OFD1 mutations, presenting with craniofacial features (macrocephaly, depressed or broad nasal bridge, and lip abnormalities), postaxial polydactyly, respiratory insufficiency with recurrent respiratory tract infections in survivors, severe mental or developmental retardation, and brain malformations (hypoplasia or agenesis of corpus callosum and/or cerebellar vermis and posterior fossa abnormalities).

Classification of functional dyspepsia based on concomitant bowel symptoms

BACKGROUND

  Functional dyspepsia (FD) is a heterogeneous disease, and categorized into postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS). However, many FD patients have overlap of both PDS and EPS. The present study was designed to examine whether FD could be categorized based on the presence of concomitant gastrointestinal symptoms.

METHODS

  A web survey comprised of the Gastrointestinal Symptom Rating Scale (GSRS), Rome III criteria of FD, and demographic information was sent to public participants who have no history of severe illness. Factor and cluster analyses were conducted to identify sub-categories of FD based on GSRS.

KEY RESULTS

  A total of 8038 participants completed the survey. A total of 563 participants met the criteria for FD, whereas 6635 participants did not have dyspepsia symptoms. The remainder had either organic disease (377) or uninvestigated dyspepsia (463). The cluster analysis categorized participants as constipation predominant (cluster C), diarrhea predominant (cluster D), or having neither diarrhea nor constipation (cluster nCnD). Cluster C and D were significantly associated with the presence of FD [odds ratio (OR) 2.57, 95% confidence interval (CI) 2.06-3.21; OR 2.80; 95% CI 2.27-3.45, respectively]. In FD, especially in PDS cases, the scores of upper gastrointestinal symptoms were higher in cluster C or D than in cluster nCnD.

CONCLUSIONS & INFERENCES

  The severity of dyspepsia symptoms is associated with the presence of bowel symptoms especially in PDS. This novel categorization of FD based on concomitant constipation or diarrhea may improve classification of patients.