Genomic analysis of inter-hospital transmission of vancomycin-resistant Enterococcus faecium sequence type 80 isolated during an outbreak in Hiroshima, Japan

Outbreaks caused by vancomycin-resistant enterococci that transcend jurisdictional boundaries are occurring worldwide. This study focused on a vancomycin-resistant enterococcus outbreak that occurred between 2018 and 2021 across two cities in Hiroshima, Japan. The study involved genetic and phylogenetic analyses using whole-genome sequencing of 103 isolates of vancomycin-resistant enterococci to identify the source and transmission routes of the outbreak. Phylogenetic analysis was performed using core genome multilocus sequence typing and core single-nucleotide polymorphisms; infection routes between hospitals were inferred using BadTrIP. The outbreak was caused by Enterococcus faecium sequence type (ST) 80 carrying the vanA plasmid, which was derived from strain A10290 isolated in India. Of the 103 isolates, 93 were E. faecium ST80 transmitted across hospitals. The circular vanA plasmid of the Hiroshima isolates was similar to the vanA plasmid of strain A10290 and transferred from E. faecium ST80 to other STs of E. faecium and other Enterococcus species by conjugation. The inferred transmission routes across hospitals suggest the existence of a central hospital serving as a hub, propagating vancomycin-resistant enterococci to multiple hospitals. Our study highlights the importance of early intervention at the key central hospital to prevent the spread of the infection to small medical facilities, such as nursing homes, with limited medical resources and a high number of vulnerable individuals.

Complete genome sequence of cfr(B)-carrying Enterococcus raffinosus isolated from bile in a patient in Japan

OBJECTIVES

Linezolid is an antibiotic used to treat infectious diseases caused by vancomycin-resistant enterococci and methicillin-resistant Staphylococcus aureus. Recently, Enterococcus Spp.-carrying mobile linezolid resistance genes were reported. Herein, we report the complete genome sequence of Enterococcus raffinosus JARB-HU0741, which was isolated from a bile sample of a patient in Japan on May 5, 2021, and carries a linezolid resistance gene, cfr(B). Nevertheless, this isolate was susceptible to linezolid.

METHODS

Whole-genome sequencing was performed using HiSeq X FIVE (Illumina) and GridION (Oxford Nanopore Technologies). The sequence reads were assembled using Unicycler v0.4.8, and the complete genome was annotated using DFAST v1.2.18. Antimicrobial resistance genes were detected with Abricate v1.0.1, using the ResFinder database. The minimum inhibitory concentrations (MICs) were determined using broth microdilution and interpreted according to the guidelines of the Clinical and Laboratory Standards Institute.

RESULTS

E. raffinosus JARB-HU0741 contained a 3 248 808-bp chromosome and a 1 156 277-bp megaplasmid. cfr(B) was present in the Tn6218-like transposon, which was inserted into a gene encoding a PRD domain-containing protein present in the megaplasmid, but the isolate was susceptible to linezolid (MIC, 0.5 µg/mL). The Tn6218-like transposon was similar to the Tn6218 of Clostridioides difficile Ox3196 and the Tn6218-like transposon of Enterococcus faecium UW11733; however, three genes encoding a topoisomerase, an S-adenosylmethionine-dependent methyltransferase, and a TetR family transcriptional regulator were present in the previous Tn6218- or Tn6218-like transposon.

CONCLUSION

This is the first report of the complete genome sequence of E. raffinosus carrying cfr(B). E. raffinosus carrying cfr(B) without linezolid resistance poses a threat, as it could serve as a reservoir for mobile linezolid resistance genes.

Complete genome sequence of optrA-carrying Enterococcus faecalis isolated from open pus in a Japanese patient

OBJECTIVES

The occurrence of linezolid resistance in enterococci has recently increased. Here, we report the genomic characterization of Enterococcus faecalis strain JARB-HU0796-isolated from the open pus of a patient in Hiroshima, Japan-which shows non-susceptibility to linezolid (MIC of 4 μg/mL).

METHODS

JARB-HU0796 whole-genome sequencing was performed using short-read sequencing with Illumina Hiseq X Five and long-read sequencing using GridION. These reads were collected using the assembly pipeline Unicycler and annotated with DFAST. Antimicrobial resistance genes were detected using the Abricate and ResFinder databases, and the sequence type identified using PubMLST. The antimicrobial susceptibility of JARB-HU0796 was determined with the Eiken dry-plate QH02 System.

RESULTS

The JARB-HU0796 complete genome contained a circular chromosome (2 722 585-bp) and two circular plasmids (85 996-bp and 58 872-bp). The chromosome harbors the optrA gene, which confers resistance to oxazolidinones and phenicols. JARB-HU0796 showed non-susceptibility to linezolid and multidrug resistance to other antibiotics. MLST analysis identified JARB-HU0796 as ST476, similar to the optrA-positive E. faecalis ST476 isolates from swine (South Korea, 2020) and pet food (Switzerland, 2022). The optrA region of JARB-HU0796 is nearly identical to that of ST476 E. faecalis strain TZ2, isolated from humans (China, 2013).

CONCLUSIONS

To the best of our knowledge, this is the first report of the complete genome sequence of E. faecalis ST476 carrying optrA on a chromosome isolated from a patient in Japan. The strain may have originated in animals, suggesting that the organisms acquired resistance to linezolid because the optrA gene may be closely spread between animals and humans.

Effect of real-time remote-based cardiac rehabilitation on subjective satisfaction and objective performance during the coronavirus disease 2019 pandemic

Background

Real-time remote-based cardiac rehabilitation (CR) programmes improve exercise capacity. However, satisfaction and performance improvements after remote-based CR remain unclear. In addition to physical function, subjective satisfaction and objective performance may be adversely affected during the coronavirus disease 2019 pandemic.

Purpose

This study aimed to compare the effectiveness of real-time remote-based CR versus hospital-based CR in improving physical function, subjective satisfaction, and objective performance (i.e., activity limitations and participation restrictions).

Methods

We conducted a quasi-randomised controlled trial and recruited 38 patients with cardiovascular disease (CVD). The patients participated in 4 weeks of hospital-based CR, followed by 12 weeks of remote or hospital-based CR based on quasi-randomised allocation. We assessed the participants at baseline and after 12 weeks of remote or hospital-based CR using the shortened version of the World Health Organization Quality of Life scale (WHOQOL-BREF) for subjective satisfaction, the World Health Organization Disability Assessment Schedule (WHODAS 2.0) for objective performance, and peak oxygen uptake (peak VO2) using the cardiopulmonary exercise test, for physical function. We evaluated individual results by measuring baseline to post-CR changes (i.e., delta [Δ]) (paired t-test) and then compared the remote and hospital-based CR programmes (unpaired t-test).

Results

Sixteen patients (72.2±10.4 years) completed remote-based CR and fifteen patients (77.3±4.8 years) completed hospital-based CR. Seven patients were excluded owing to other health complications (n=2) and inability to attend hospital based-CR (n=5). In the remote-based CR group, the peak VO2 (before: 12.0±2.7 mL min^–1 kg^–1; after: 14.9±3.9 mL min^–1 kg^–1; p<0.05) and the WHOQOL-BREF score (before: 77.4±12.8 points; after: 93.9±12.9 points; p<0.001) were significantly higher, whereas the WHODAS 2.0 score was significantly lower (before: 19.9±13.2 points; after: 11.3±6.8 points; p<0.05) after rehabilitation than at baseline. The post-CR physical function differed significantly between the two groups (Δpeak VO2, remote: 2.8±3.0 mL min^–1 kg^–1; hospital: 0.84±1.8 mL min^–1 kg^–1; p<0.05). The post-CR change in the WHOQOL-BREF score was not significantly different between the groups. The post-CR change in the WHODAS 2.0 score was significantly lower in the remote-based CR group than in the hospital-based CR group. (ΔWHODAS 2.0 score, remote: –8.56±14.2 points; hospital: 2.14±7.6 points; p<0.01).

Conclusions

Remote-based CR significantly improved physical function and objective performance in patients with CVD. Remote-based CR could be an effective treatment for stable patients who are unable to visit the hospital during the coronavirus disease 2019 pandemic. In the future, risk stratification according to severity of illness is needed.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Sanei Medicis company.

Two ABC transport systems carry out peptide uptake in Enterococcus faecalis: Their roles in growth and in uptake of sex pheromones

Enterococcal pheromone-inducible plasmids encode a predicted OppA-family secreted lipoprotein. In the case of plasmid pCF10, the protein is PrgZ, which enhances the mating response to cCF10 pheromone. OppA proteins generally function with associated OppBCDF ABC transporters to import peptides. In this study, we analyzed the potential interactions of PrgZ with two host-encoded Opp transporters using two pheromone-inducible fluorescent reporter constructs. Based on our results, we propose renaming these loci opp1 (OG1RF_10634-10639) and opp2 (OG1RF_12366-12370). We also examined the ability of the Opp1 and Opp2 systems to mediate import in the absence of PrgZ. Cells expressing PrgZ were able to import pheromone if either opp1 or opp2 was functional, but not if both opp loci were disrupted. In the absence of PrgZ, pheromone import was dependent on a functional opp2 system, including opp2A. Comparative structural analysis of the peptide-binding pockets of PrgZ, Opp1A, Opp2A, and the related Lactococcus lactis OppA protein, suggested that the robust pheromone-binding ability of PrgZ relates to a nearly optimal fit of the hydrophobic peptide, whereas binding ability of Opp2A likely results from a more open, promiscuous peptide-binding pocket similar to L. lactis OppA.

Dissemination of IncF group F1:A2:B20 plasmid-harbouring multidrug-resistant Escherichia coli ST131 before the acquisition of blaCTX-M in Japan

OBJECTIVES

The Escherichia coli O25-ST131 clone is responsible for global dissemination of the bla_CTX-M gene. However, the prevalence of this clone in the digestive tract, devoid of antimicrobial selection, and its molecular epidemiology remain unclear. In this study, we examined the origin of bla_CTX-M-positive E. coli O25-ST131 and its distribution.

METHODS

We separately sequenced the chromosomal and plasmid genomes of 50 E. coli O25 isolates obtained from faecal samples of patients with diarrhoea in Japan.

RESULTS

Although 36 (72%) of 50 E. coli O25 isolates were ST131, only 6 harboured bla_CTX-M. According to the fimH and ybbW sequences and fluoroquinolone susceptibility, H30R1 isolates were dominant (27/36; 75%) and possessed IncFII-FIA-FIB with FAB formula subtype F1:A2:B20 plasmids at a high frequency (24/27; 89%). The F1:A2:B20 plasmids possessed more resistance genes such as bla_TEM-1, aminoglycoside resistance genes and trimethoprim/sulfamethoxazole resistance genes compared with non-F1:A2:B20 plasmids. In contrast, only one bla_CTX-M-14 gene was located on the F1:A2:B20 plasmids, whereas the other three were located on IncFII (F4:A-:B-) (n = 1) and IncZ (n = 2) plasmids. Two H30Rx-ST131 isolates harboured bla_CTX-M-15: one was on the chromosome and the other on the IncFIA-R plasmid. The stability and conjugation ability of the F1:A2:B20 plasmids were compared with those of non-F1:A2:B20 plasmids, which revealed higher stability but lower conjugative ability.

CONCLUSIONS

These results suggest that E. coli H30R1-ST131 is a multidrug-resistant clone containing several resistance genes in the F1:A2:B20 plasmid, which were widely distributed before the acquisition of bla_CTX-M.

Potential KPC-2 carbapenemase reservoir of environmental Aeromonas hydrophila and Aeromonas caviae isolates from the effluent of an urban wastewater treatment plant in Japan

Aeromonas hydrophila and Aeromonas caviae adapt to saline water environments and are the most predominant Aeromonas species isolated from estuaries. Here, we isolated antimicrobial-resistant (AMR) Aeromonas strains (A. hydrophila GSH8-2 and A. caviae GSH8M-1) carrying the carabapenemase bla_KPC-2 gene from a wastewater treatment plant (WWTP) effluent in Tokyo Bay (Japan) and determined their complete genome sequences. GSH8-2 and GSH8M-1 were classified as newly assigned sequence types ST558 and ST13, suggesting no supportive evidence of clonal dissemination. The strains appear to have acquired bla_KPC-2 -positive IncP-6-relative plasmids (pGSH8-2 and pGSH8M-1-2) that share a common backbone with plasmids in Aeromonas sp. ASNIH3 isolated from hospital wastewater in the United States, A. hydrophila WCHAH045096 isolated from sewage in China, other clinical isolates (Klebsiella, Enterobacter and Escherichia coli), and wastewater isolates (Citrobacter, Pseudomonas and other Aeromonas spp.). In addition to bla_KPC-2 , pGSH8M-1-2 carries an IS26-mediated composite transposon including a macrolide resistance gene, mph(A). Although Aeromonas species are opportunistic pathogens, they could serve as potential environmental reservoir bacteria for carbapenemase and AMR genes. AMR monitoring from WWTP effluents will contribute to the detection of ongoing AMR dissemination in the environment and might provide an early warning of potential dissemination in clinical settings and communities.

Characterization of NDM-5- and CTX-M-55-coproducing Escherichia coli GSH8M-2 isolated from the effluent of a wastewater treatment plant in Tokyo Bay

Purpose

New Delhi metallo-β-lactamase (NDM)-5-producing Enterobacteriaceae have been detected in rivers, sewage, and effluents from wastewater treatment plants (WWTPs). Environmental contamination due to discharged effluents is of particular concern as NDM variants may be released into waterways, thereby posing a risk to humans. In this study, we collected effluent samples from a WWTP discharged into a canal in Tokyo Bay, Japan.

Methods

Testing included the complete genome sequencing of Escherichia coli GSH8M-2 isolated from the effluent as well as a gene network analysis.

Results

The complete genome sequencing of GSH8M-2 revealed that it was an NDM-5-producing E. coli strain sequence type ST542, which carries multiple antimicrobial resistance genes for β-lactams, quinolone, tetracycline, trimethoprim-sulfamethoxazole, florfenicol/chloramphenicol, kanamycin, and fosfomycin. The bla _NDM-5 gene was found in the IncX3 replicon plasmid pGSH8M-2-4. Gene network analysis using 142 IncX3 plasmid sequences suggested that pGSH8M-2-4 is related to both clinical isolates of  E. coli and Klebsiella species in Eastern Asia. GSH8M-2 also carries the bla _CTX-M-55 gene in IncX1 plasmid pGSH8M-2-3.

Conclusion

This is the first report of environmental NDM-5-producing E. coli isolated from a WWTP in Japan. NDM-5 detection is markedly increasing in veterinary and clinical settings, suggesting that dual β-lactamases, such as NDM-5 and CTX-M-55, might be acquired through multiple steps in environment settings. Environmental contamination through WWTP effluents that contain producers of NDM variants could be an emerging potential health hazard. Thus, regular monitoring of WWTP effluents is important for the detection of antimicrobial-resistant bacteria that may be released into the waterways and nearby communities.

The Space Physics Environment Data Analysis System (SPEDAS)

With the advent of the Heliophysics/Geospace System Observatory (H/GSO), a complement of multi-spacecraft missions and ground-based observatories to study the space environment, data retrieval, analysis, and visualization of space physics data can be daunting. The Space Physics Environment Data Analysis System (SPEDAS), a grass-roots software development platform (www.spedas.org), is now officially supported by NASA Heliophysics as part of its data environment infrastructure. It serves more than a dozen space missions and ground observatories and can integrate the full complement of past and upcoming space physics missions with minimal resources, following clear, simple, and well-proven guidelines. Free, modular and configurable to the needs of individual missions, it works in both command-line (ideal for experienced users) and Graphical User Interface (GUI) mode (reducing the learning curve for first-time users). Both options have "crib-sheets," user-command sequences in ASCII format that can facilitate record-and-repeat actions, especially for complex operations and plotting. Crib-sheets enhance scientific interactions, as users can move rapidly and accurately from exchanges of technical information on data processing to efficient discussions regarding data interpretation and science. SPEDAS can readily query and ingest all International Solar Terrestrial Physics (ISTP)-compatible products from the Space Physics Data Facility (SPDF), enabling access to a vast collection of historic and current mission data. The planned incorporation of Heliophysics Application Programmer's Interface (HAPI) standards will facilitate data ingestion from distributed datasets that adhere to these standards. Although SPEDAS is currently Interactive Data Language (IDL)-based (and interfaces to Java-based tools such as Autoplot), efforts are under-way to expand it further to work with python (first as an interface tool and potentially even receiving an under-the-hood replacement). We review the SPEDAS development history, goals, and current implementation. We explain its "modes of use" with examples geared for users and outline its technical implementation and requirements with software developers in mind. We also describe SPEDAS personnel and software management, interfaces with other organizations, resources and support structure available to the community, and future development plans.

ELECTRONIC SUPPLEMENTARY MATERIAL

The online version of this article (10.1007/s11214-018-0576-4) contains supplementary material, which is available to authorized users.

The effects of teriparatide on acceleration of bone healing following atypical femoral fracture: comparison between daily and weekly administration

We compared the effectiveness of promoting bone healing between two teriparatide preparations for atypical femoral fracture (AFF). A total of 45 AFFs were included in this study, and we compared the duration of bone union. Teriparatide administered by daily injection enhanced bone union more than weekly administration in complete AFFs.

INTRODUCTION

The efficacy of teriparatide for atypical femoral fracture (AFF) has been recently reported. Although two different teriparatide preparations can be used to treat osteoporosis in Japan, daily or weekly injection, all previous reports on the effectiveness of teriparatide for AFF only examined daily injection formulations. Therefore, we compared the promotion of bone healing between the two teriparatide preparations for AFF.

METHODS

A total of 45 consecutive AFFs in 43 Japanese patients were included in this study. They received either a daily 20-μg teriparatide injection (daily group; n = 32) or a once-a-week 56.5-μg teriparatide injection (weekly group; n = 13). We compared the clinical background and duration of bone union between these two groups.

RESULTS

When all patents were included, the fracture healing time was not significantly different between the two groups. Only patients with complete AFFs had significantly fewer daily bisphosphonate or denosumab injections than the weekly group (P < 0.05). The fracture healing time in the daily group (6.1 ± 4.1 months) was significantly shorter than that in the weekly group (10.1 ± 4.2 months) (P < 0.05). Even if the influence of bisphosphonate or denosumab usage was excluded, a similar significant difference was observed in the fracture healing time (P < 0.05). There was no significant difference between the two groups among patients with incomplete AFFs.

CONCLUSIONS

Daily teriparatide injections enhance bone union more than weekly injections in complete AFF patients.

Complete Genome Sequence of a blaKPC-2-Positive Klebsiella pneumoniae Strain Isolated from the Effluent of an Urban Sewage Treatment Plant in Japan

Antimicrobial resistance genes (ARGs) and the bacteria that harbor them are widely distributed in the environment, especially in surface water, sewage treatment plant effluent, soil, and animal waste. In this study, we isolated a KPC-2-producing Klebsiella pneumoniae strain (GSU10-3) from a sampling site in Tokyo Bay, Japan, near a wastewater treatment plant (WWTP) and determined its complete genome sequence. Strain GSU10-3 is resistant to most β-lactam antibiotics and other antimicrobial agents (quinolones and aminoglycosides). This strain is classified as sequence type 11 (ST11), and a core genome phylogenetic analysis indicated that strain GSU10-3 is closely related to KPC-2-positive Chinese clinical isolates from 2011 to 2017 and is clearly distinct from strains isolated from the European Union (EU), United States, and other Asian countries. Strain GSU10-3 harbors four plasmids, including a blaKPC-2-positive plasmid, pGSU10-3-3 (66.2 kb), which is smaller than other blaKPC-2-positive plasmids and notably carries dual replicons (IncFII [pHN7A8] and IncN). Such downsizing and the presence of dual replicons may promote its maintenance and stable replication, contributing to its broad host range with low fitness costs. A second plasmid, pGSU10-3-1 (159.0 kb), an IncA/C2 replicon, carries a class 1 integron (containing intI1, dfrA12, aadA2, qacEΔ1, and sul1) with a high degree of similarity to a broad-host-range plasmid present in the family Enterobacteriaceae The plasmid pGSU10-3-2 (134.8 kb), an IncFII(K) replicon, carries the IS26-mediated ARGs [aac(6')Ib-cr,blaOXA-1, catB4 (truncated), and aac(3)-IId], tet(A), and a copper/arsenate resistance locus. GSU10-3 is the first nonclinical KPC-2-producing environmental Enterobacteriaceae isolate from Japan for which the whole genome has been sequenced.IMPORTANCE We isolated and determined the complete genome sequence of a KPC-2-producing K. pneumoniae strain from a sampling site in Tokyo Bay, Japan, near a wastewater treatment plant (WWTP). In Japan, the KPC type has been very rarely detected, while IMP is the most predominant type of carbapenemase in clinical carbapenemase-producing Enterobacteriaceae (CPE) isolates. Although laboratory testing thus far suggested that Japan may be virtually free of KPC-producing Enterobacteriaceae, we have detected it from effluent from a WWTP. Antimicrobial resistance (AMR) monitoring of WWTP effluent may contribute to the early detection of future AMR bacterial dissemination in clinical settings and communities; indeed, it will help illuminate the whole picture in which environmental contamination through WWTP effluent plays a part.

Improved control of childhood asthma with low-dose, short-term vitamin D supplementation: a randomized, double-blind, placebo-controlled trial

BACKGROUND

In our prior randomized trial on preventing influenza, asthma attacks as a secondary outcome occurred less often in the vitamin D group than in the placebo group. We aimed to clarify whether low-dose, short-term vitamin D supplementation, in addition to standard treatments, improves control of childhood asthma.

METHODS

We conducted a randomized, double-blind, placebo-controlled trial comparing vitamin D3 supplements (800 IU/day) with placebo for 2 months in schoolchildren with asthma. The primary outcomes were frequency and severity of asthma judging from changes in asthma control levels defined by the Global Initiative for Asthma (GINA) by collaborating doctors at 2 and 6 months.

RESULTS

Japanese schoolchildren with asthma (n = 89) were randomly assigned to receive vitamin D (n = 54) or placebo (n = 35). At 2 months, GINA asthma control was significantly more improved in the vitamin D group compared with the placebo group (P = 0.015). Childhood asthma control test (CACT) scores, a secondary outcome, were also significantly (P = 0.004) improved in the vitamin D group compared with the placebo group at 2 months, and differences remained significant (P = 0.012) at 6 months. The proportion of patients with a peak expiratory flow rate <80% predicted was significantly less in the vitamin D group (8/54: 15%) than in the placebo group (12/35: 34%) at 6 months (P = 0.032).

CONCLUSIONS

Low-dose, short-term vitamin D supplementation in addition to standard treatment may improve levels of asthma control in schoolchildren.

Age-related alteration of expression and function of TLRs and NK activity in oral candidiasis

OBJECTIVE

Roles of aging or immune responses mediated by Toll-like receptors and natural killer cell in the onset or progression of human candidiasis remain unclear. This study was designed to elucidate the roles using peripheral blood mononuclear cells from healthy donors and patients with oral candidiasis.

SUBJECTS AND METHODS

Subjects tested were healthy volunteers and patients who visited Dental Clinical Division of Hokkaido University Hospital. The patients with oral candidiasis included 39 individuals (25-89 years of age) with major complaints on pain in oral mucosa and/or dysgeusia. Healthy volunteers include students (25-35 years of age) and teaching staffs (50-65 years of age) of Hokkaido University Graduate School of Dental Medicine.

RESULTS

Functions of Toll-like receptors 2 and 4 were downregulated significantly and the natural killer activity was slightly, but not significantly downregulated in aged healthy volunteers compared with healthy young volunteers. Functions of Toll-like receptors 2 and 4 and the natural killer activity were significantly downregulated in patients with oral candidiasis compared with healthy volunteers.

CONCLUSION

Downregulation of functions of Toll-like receptors 2 and 4 as well as natural killer activity is suggested to be associated with the onset or progression of oral candidiasis in human.

Leptospira-rat-human relationship in Luzon, Philippines

Leptospirosis is a zoonotic infection that is caused by the pathogenic species of Leptospira. Rats are the most important reservoirs of these organisms. Our study aimed to characterize Leptospira isolates from humans and rats and elucidate the Leptospira-rat-human relationship in Luzon, Philippines. Forty strains were isolated from humans and rats. The isolates were confirmed to be Leptospira and pathogenic through rrl- and flaB-PCR, respectively. Around 73% of the isolates were found to be lethal to hamsters. Serotyping showed that there were mainly three predominant leptospiral serogroups in the study areas namely Pyrogenes, Bataviae, and Grippotyphosa. Gyrase B gene sequence analysis showed that all the isolates belonged to Leptospira interrogans. Most had 100% similarity with serovar Manilae (15/40), serovar Losbanos (8/40), and serogroup Grippotyphosa (8/40). Strains from each group had highly identical pulsed-field gel electrophoresis patterns and were further grouped as A (Pyrogenes, 14), B (Bataviae, 8), and C (Grippotyphosa, 10). Results further revealed that similar serotypes were isolated from both humans and rats in the same areas. It is suggested that these three predominant groups with highly similar intra-group PFGE patterns may have been primarily transmitted by rats and persistently caused leptospirosis in humans particularly in the Luzon islands.

Identification of leptospiral 3-hydroxyacyl-CoA dehydrogenase released in the urine of infected hamsters

Background

Leptospirosis is a global zoonosis caused by pathogenic Leptospira. The non-specific clinical signs and symptoms of leptospirosis lead to its misdiagnosis. To date, there is still no reliable rapid test kit that can accurately diagnose leptospirosis at bedside or in field. In this research, with the ultimate goal of formulating a rapid and accurate diagnostic tool for leptospirosis, we aimed to identify leptospiral proteins excreted in urine of infected hamsters, which are thought to mimic Weil’s disease.

Results

Hamsters were subcutaneously infected with leptospires, and the general attributes of urine as well as the proteins excreted in it were examined. Some leptospiral proteins were found to be excreted in the urine from the early phase of infection. The most important finding of this study was the detection of the lipid-metabolizing enzyme, 3-hydroxyacyl-CoA dehydrogenase (HADH), before the onset of illness, when leptospires were not yet detected in the urine of infected hamsters.

Conclusions

This is the first report on the detection of leptospiral HADH in the host urine, which may be a possible candidate leptospiral antigen that can be used in the early diagnosis of human and animal leptospirosis.

High virulence in hamsters of four dominant Leptospira serovars isolated from rats in the Philippines

Leptospirosis is caused by pathogenic species of Leptospira. The aim of this study was to determine and characterize the pathogenicity of four dominant Leptospira isolates prevailing among rats in the Philippines. The isolates were Leptospira interrogans serovar Manilae strain K64, L. interrogans serovar Losbanos strain K37, L. interrogans serovar Ratnapura strain K5 and Leptospira borgpetersenii serovar Javanica strain K6. Pathogenicities were studied using hamsters, which reproduce severe human leptospirosis. The minimum lethal doses were 10(0) ( = 1) leptospires for K64, K37 and K5, and 10(1) leptospires for K6. Weight loss amongst the Leptospira-infected hamsters was observed from 1 day before death (K64-, K37- and K5-infected hamsters) to as much as 1 week before death for K6-infected hamsters. Similar and varied gross and microscopic lesions were observed amongst infected hamsters, even for strains belonging to the same species (i.e. L. interrogans). The most significant and common histopathological findings were congestion of the glomerulus, disarrangement of hepatic cords and erythrophagocytosis. Other findings were foamy splenic macrophages for K6, severe petechial pulmonary haemorrhage for K64, and hematuria and severe pulmonary congestion for K37. Immunostaining and culture revealed the presence of leptospires in different organs of the infected hamsters. Based on these results, Leptospira isolates from rats in the Philippines were shown to be highly virulent, causing pulmonary haemorrhage, severe hepato-renal damage and death in hamsters even at lower doses. The present findings on experimental leptospirosis support clinical data showing that patients with severe manifestations of leptospirosis, such as pulmonary haemorrhage, are increasing in the Philippines. These findings may serve as a basis to strengthen the early diagnosis and treatment of human leptospirosis.

Transcriptional units of GAL genes in Saccharomyces cerevisiae determined by ultraviolet light mapping

The size of the transcriptional unit of the structural genes for three galactose-metabolizing enzymes which form a cluster on chromosome II in Saccharomyces cerevisiae was studied by the ultraviolet light (UV)-mapping technique. Thus the size of the primary transcripts of GAL7 for galactose-1-phosphate uridylyl transferase, GAL10 for uridine diphosphoglucose 4-epimerase, or GAL1 for galactokinase were estimated to be 0.81 x 10(6), 1.1 x 10(6), or 1.3 x 10(6) respectively. In the light of these data together with the known directions of transcription of the genes, we concluded that each of three genes was transcribed from its own promoter.

Toll-like receptor 2-mediated modulation of growth and functions of regulatory T cells by oral streptococci

This study was designed to determine whether oral streptococci modulate the growth and functions of regulatory T cells. Heat-killed cells of wild-type strains of Streptococcus gordonii and Streptococcus mutans induced the Toll-like receptor 2 (TLR2) -mediated nuclear factor-κB (NF-κB) activation, but their lipoprotein-deficient strains did not. Stimulation with these streptococci resulted in a significant increase in the frequency of CD4(+) CD25(+) Foxp3(+) regulatory T cells in splenocytes derived from both TLR2(+/+) and TLR2(-/-) mice, but the level of increase in TLR2(+/+) splenocytes was stronger than that in TLR2(-/-) splenocytes. Both strains of S. gordonii enhanced the proliferation of CD4(+) CD25(+) Foxp3(+) regulatory T cells isolated from TLR2(+/+) mice at the same level as those from TLR2(-/-) mice in an interleukin-2-independent manner. However, wild-type and lipoprotein-deficient strains of both streptococci did not enhance the suppressive activity of the isolated regulatory T cells in vitro, but rather inhibited it. TLR ligands also inhibited the suppressive activity of the regulatory T cells. Inhibition of the suppressive activity was recovered by the addition of anti-IL-6 antibody. Pretreatment of antigen-presenting cells with the NF-κB inhibitor BAY11-7082 enhanced the suppressive activity of the regulatory T cells. These results suggested that interleukin-6 produced by antigen-presenting cells inhibits the suppressive activity of the regulatory T cells. Wild-type strain, but not lipoprotein-deficient strain, of S. gordonii reduced the frequency of CD4(+)  CD25(+)  Foxp3(+) regulatory T cells in the acute infection model, whereas both strains of S. gordonii increased it in the chronic infection model mice. Hence, this study suggests that oral streptococci are capable of modulating the growth and functions of regulatory T cells in vitro and in vivo.

Brain localization of leucine-rich α2-glycoprotein and its role

OBJECTIVES

We have previously reported that the level of leucine-rich alpha-2-glycoprotein (LRG) expression is specifically increased in cerebrospinal fluid (CSF) of idiopathic normal pressure hydrocephalus (INPH). The objective of this study is to examine the localization of LRG - the cerebral areas where it is expressed.

METHOD

The histological sections of autopsied brain specimens from ten subjects, five adult cases (mean age 43.6 years; range 34-50 years) and five senile cases (mean age 76.0 years; range 67-88 years) were prepared, multistained with antibodies against human LRG, glial fibrillary acidic protein (GFAP), CD31, and aquaporin-4 (AQP4), and reviewed for the expression sites of LRG.

RESULTS

Immunostains of GFAP and LRG were compared in standard brain specimens from elderly patients. The results indicated that LRG is distributed throughout the entire brain, with especially high expression in the deep cerebral cortex. In addition, the cells that express LRG showed similar morphology to astrocytes. Double staining of CD31 and LRG revealed a significant expression of LRG in the pericapillary regions. The expression was observed in resident astrocytes, as well as in the capillary vessel to which astrocytic processes grow and adhere. When age-related comparisons were made between senile and adult specimens, LRG expression increased with age.

CONCLUSION

LRG expression in resident astrocytes increased with age.

Combined Treatment of Alendronate and Low-Intensity Pulsed Ultrasound (LIPUS) Increases Bone Mineral Density at the Cancellous Bone Osteotomy Site in Aged Rats: A Preliminary Study

Introduction: During fracture healing, alendronate encourages callus volume by inhibiting bone resorption, whereas low-intensity pulsed ultrasound (LIPUS) enhances bone regeneration by promoting an anabolic response. Methods: In the present study, 9-month-old Sprague-Dawley rats, with a unilateral proximal tibial osteotomy, were treated with alendronate (daily, 1 g/kg) plus sham-LIPUS (n = 14), saline plus LIPUS (20 min/day) (n = 18), alendronate plus LIPUS (n = 16), or saline plus sham- LIPUS as a control (n = 13) for 4 weeks. The rats were then examined for changes in bone mineral density (BMD) during metaphyseal bone repair. Results: The combined therapy signi cantly increased BMD at the osteotomy site at 4 weeks (p < 0.001) compared with the control, without affecting the contralateral, non-osteotomized tibia. Both alendronate and LIPUS alone also exerted a positive, albeit less, effect on BMD in the affected limb (p < 0.001 and p = 0.006, respectively). Conclusions: Alendronate and LIPUS cooperate to enhance BMD during metaphyseal bone healing. Keywords: LIPUS, bisphosphonate, bone mineral density.

Combined treatment of alendronate and low-intensity pulsed ultrasound (LIPUS) increases bone mineral density at the cancellous bone osteotomy site in aged rats: a preliminary study

INTRODUCTION

During fracture healing, alendronate encourages callus volume by inhibiting bone resorption, whereas low-intensity pulsed ultrasound (LIPUS) enhances bone regeneration by promoting an anabolic response.

METHODS

In the present study, 9-month-old Sprague-Dawley rats, with a unilateral proximal tibial osteotomy, were treated with alendronate (daily, 1 µg/kg) plus sham-LIPUS (n = 14), saline plus LIPUS (20 min/day) (n = 18), alendronate plus LIPUS (n = 16), or saline plus sham-LIPUS as a control (n = 13) for 4 weeks. The rats were then examined for changes in bone mineral density (BMD) during metaphyseal bone repair.

RESULTS

The combined therapy significantly increased BMD at the osteotomy site at 4 weeks (p < 0.001) compared with the control, without affecting the contralateral, non-osteotomized tibia. Both alendronate and LIPUS alone also exerted a positive, albeit less, effect on BMD in the affected limb (p < 0.001 and p = 0.006, respectively).

CONCLUSION

Alendronate and LIPUS cooperate to enhance BMD during metaphyseal bone healing.

The influence of Epstein-Barr virus reactivation in patients with Graves' disease

In Graves' disease, the IgG class autoantibody against thyrotropin receptor (TRAb) is produced excessively and induces hyperthyroidism. Epstein-Barr virus (EBV) is one of the human herpesviruses that persists for life, mainly in B lymphocytes, and is occasionally reactivated. Therefore, EBV may affect the antibody production of B lymphocytes that would normally produce TRAb. The purpose of the present study was to evaluate the association of EBV reactivation with the etiology of Graves' disease. Serum levels of EBV antibodies and IgE were determined by ELISA. TRAb levels were determined by radioreceptor assay. We performed in-situ hybridization (ISH) of EBV-encoded small RNA (EBER)1 on the thyroid tissue of one of our patients. In Graves' disease patients with TRAb levels ≥ 10%, EA antibody levels, which indicate EBV reactivation, were moderately but significantly correlated with the levels of TRAb, and weakly but significantly correlated with IgE. EBER1-ISH revealed that one of our patients had EBV-infected lymphocytes infiltrating the thyroid gland. EBV reactivation may stimulate antibody-producing B lymphocytes predisposed to make TRAb, and this may contribute to or exacerbate the disease.

Health-related quality-of-life after external beam radiation therapy for localized prostate cancer: intensity-modulated radiation therapy versus conformal radiation therapy

We compared health-related quality-of-life (HRQL) after intensity-modulated radiotherapy (IMRT) with statuses obtained after old and new protocols of three-dimensional conformal radiation therapy (3DCRT) for localized prostate cancer. We measured the general and disease specific HRQL using the MOS 36-Item Health Survey (SF-36), and the University of California, Los Angeles Prostate Cancer Index (UCLA PCI), respectively. IMRT resulted in similar profiles of general and disease-specific HRQL to two other methods within the first year after treatment. Moreover, IMRT gave rise to comparable urinary, intestinal and sexual side effects despite the high dose of radiation applied.

Androgen receptor mutation (T877A) promotes prostate cancer cell growth and cell survival

Alteration of the AR functions due to amplification, overexpression and somatic mutation of the AR itself or altered interaction of AR with other cell growth regulatory proteins, may contribute to a significant subset of advanced prostate cancer (CaP). Very little is known about the pathways impacted by AR dysfunctions, although CaP associated AR alterations suggest the biological role of the AR dysfunction in disease progression. Comparative evaluations of wild type (wt) AR and mutant (mt) ARs in appropriate experimental models should provide a better understanding of the functional impact of AR alterations in CaP. Here, we provide direct evidence showing cell growth/cell survival promoting effects of the widely studied CaP associated AR mutation (T877A). In contrast to Ad-wtAR or Ad-control infected LNCaP or LAPC4 cells, Ad-mtAR (T877A) infected LNCaP or LAPC4 cells continued to grow in the androgen-deprived medium and exhibited an androgen independent AR-transcription factor activity. Further, Ad-mtAR (T877A) infected LNCaP or LAPC4 cells exhibited enhanced cell growth in the presence of lower concentrations of the synthetic androgen, R1881. Of note, Ad-mtAR (T877A) infected LNCaP cells showed striking resistance to cell growth inhibition/apoptosis mediated by the wt p53. Taken together, these findings provide novel insights into the AR dysfunctions resulting from the T877A mutation and functionally similar AR alterations may provide selective cell growth/survival advantage for CaP progression. These observations have important implications for developing biology-based prognostic biomarkers and therapeutic strategies for CaP showing such AR dysfunctions.

Effective treatment of advanced solid tumors by the combination of arsenic trioxide and L-buthionine-sulfoximine

Clinical application of anticancer agents has been often hampered by toxicity against normal cells, so the achievement of their cancer-specific action is still one of the major challenges to be addressed. Previously, we reported that arsenic trioxide (As2O3) could be a promising new drug against not only leukemia but also solid tumors. The cytotoxicity of As2O3 occurred through the generation of reactive oxygen species (ROS), thus inhibiting radical scavenging systems would enhance the therapeutic efficacy of As2O3 provided that normal cells were relatively resistant to such a measure. Here, we report that the combination therapy of As2O3 with L-buthionine-sulfoximine (BSO), which inhibits a critical step in glutathione synthesis, effectively enhanced in vitro growth inhibition effect of As2O3 on all 11 investigated cell lines arising from prostate, breast, lung, colon, cervix, bladder, and kidney cancers, compared with As2O3 treatment alone. Furthermore, this combination enhanced cytotoxicity to cell lines from prostate cancer with less toxicity to those from normal prostate. In vitro cytotoxic assay using ROS-related compounds demonstrated that hydrogen peroxide (H2O2) is a major cytotoxic mediator among ROS molecules. Biochemical analysis showed that combined use of As2O3 and BSO blocked H2O2-scavenging systems including glutathione, catalase, and glutathione peroxidase, and that the degree of this blockade was well correlated with intracellular ROS levels and sensitivity to this treatment. Finally, the effectiveness of the combination therapy of As2O3 with BSO was demonstrated with an orthotopic model of prostate cancer metastasis. We propose that the combination therapy of As2O3 with BSO is a valid means of blockade of H2O2-scavenging system, and that the combination of a ROS-generating agent with an inhibitor of major scavenging systems is effective in terms of both efficacy and selectivity. Furthermore, because the effective doses of both compounds are within clinically achievable range, this report will lead to immediate benefit for the development of a new cancer therapy.