Intra-articular injection versus interscalene brachial plexus block for acute-phase postoperative pain management after arthroscopic shoulder surgery.

BACKGROUND: The minimally invasive approach of arthroscopic shoulder surgery is beneficial; however, for optimal outcomes, perioperative pain management is essential. This cross-sectional study aimed to examine the analgesic effectiveness of intra-articular injection (IA) versus interscalene brachial plexus block (ISPB) among patients treated with arthroscopic shoulder surgeries. METHODS: We reviewed 100 consecutive patients who underwent shoulder arthroscopic surgery, of whom 50 each underwent IA (February 2019─January 2020; IA group) and ISPB (October 2018─July 2019; ISPB group). The primary outcome was the postoperative pain score measured using a Wong-Baker FACES Pain Rating Scale preoperatively and at 2, 6, 12, 24, and 48 h postoperatively. We performed multiple regression analysis to examine whether IA/ISPB selection is associated with acute-phase postoperative pain and adjusted for intra-articular injection, interscalene brachial plexus block, postoperative pain management, arthroscopic shoulder surgery, IA with 10 mg of morphine previously reported prognostic factors for postoperative pain (e.g., surgical procedures, operative time, older age, and preoperative pain). Furthermore, we examined induction time, total pentazocine dosage, and total postoperative nausea and vomiting (PONV) events. RESULTS: There were no significant differences between the IA and ISPB groups in perioperative pain control during the acute-phase periods (p = 0.12, repeated analysis of variance). The difference in anesthesia method was not a prognostic factor for acute-phase postoperative pain (p = 0.11). The IA group (15.06 ± 4.00 min) had a significantly shorter mean anesthesia induction time than the ISPB group (29.23 ± 9.22 min) (p = 0.0001). There was no significant between-group difference in the total pentazocine dosage during the first 7 days (p = 0.3934) postoperatively. PONV was observed in eight (17.0%) and two (4.2%) patients in the IA and ISPB groups, respectively. There was no significant between-group difference in the PONV incidence (p = 0.1582). CONCLUSIONS: There was no significant difference in acute-phase postoperative pain management between the IA and ISPB groups. The induction time was significantly shorter in IA. IRB: Approval number: UOEHCRB20-078, IRB approval date: September 9th, 2020; study duration: October 2018 to January 2020.

Effect of dissolved oxygen on methane production from bottom sediment in a eutrophic stratified lake.

Clarifying the role of sulfate and dissolved oxygen (DO) in methane production may allow for precise and accurate modeling of methane emissions in eutrophic lakes. We conducted field observations of sulfate, methane, and DO concentrations in Lake Abashiri, a typical brackish and eutrophic lake in a cold region, to develop a DO-based method for quantitively estimating methane production in a eutrophic lake and analyzed the results. We found that sulfate concentrations decreased rapidly from 900.0 mg/L in water overlying the sediments to nearly 0.0 mg/L in the bottom sediment. Methane production was almost uniform across sediment depths of 0.05 to 0.25 m, ranging from 1400 to 1800 µmol/m2/day. Also, methane production was found to be a function of DO concentrations in water overlying the bottom and could be modeled by a logistic function: constant production at 1,400 µmol/m2/day for DO concentrations of 0.0 to 3.0 mg/L, rapidly decreasing to 0 µmol/m2/day for DO concentrations of 3.0 to 6.0 mg/L. This methane model was verified using a simple one-dimensional numerical model that showed good agreement with field observations. Our results thus suggest that the proposed methane model reduces uncertainty in estimating methane production in a eutrophic lake.

Methylglyoxal as a prognostic factor in patients with chronic kidney disease.

AIM: Advanced glycation end products and their precursors cause vascular damage through oxidative stress. We investigated the hypothesis that methylglyoxal (MG), 3-deoxyglucosone (3-DG) and pentosidine influence outcomes of chronic kidney disease (CKD) patients. METHODS: We conducted a 3 years prospective observational study involving 150 outpatients at CKD stages 3-5. At enrolment, MG, 3-DG and pentosidine plasma concentrations were measured; patients were divided into tertiles according to the concentration of each substance. The primary endpoint was death, a cardiovascular event or end-stage renal disease. Survival analysis was performed using the Cox regression model. RESULTS: The patients' mean age was 62 ± 12 years, 97 were men, and 20 had diabetic nephropathy. The mean estimated glomerular filtration rate was 25.0 ± 12.1 mL/min per 1.73 m2 , which negatively correlated with MG but not with 3-DG and pentosidine. Forty-eight patients reached the primary endpoint. Compared with the lowest MG tertile, the hazard ratio for the primary endpoint was 7.57 (95% confidence interval (CI): 1.71-33.54) in the middle tertile and 27.00 (CI: 6.46-112.82) in the highest tertile. When adjusted for characteristics at baseline, the corresponding hazard ratio decreased to 2.09 (CI: 0.37-11.96) and 6.13 (CI: 0.97-38.82), but MG tertile remained an independent risk factor for the primary endpoint. However, 3-DG and pentosidine were not related to the primary outcome. CONCLUSION: Methylglyoxal has a close clinical association with CKD. Higher MG concentrations may contribute renal function deterioration in CKD. In CKD patients, MG concentration might be useful when determining the prognosis.

Assessment of distributed hydrological model performance for simulation of multi-heavy-metal transport in Harrach River, Algeria.

This paper aims to assess the performance of a distributed hydrological model for simulating the transport of various heavy metals in rivers, to enhance and support environmental monitoring strategies for rivers in developing countries. In this context, we evaluated the performance of the Geophysical flow Circulation (GeoCIRC) model based on Object-Oriented Design (OOD) for the simulation of contamination from multiple heavy metals (Pb, Hg, Cr, and Zn) in Harrach River in Algeria. The results of the case study were in good agreement with the observations. Methodology for the assessment of data quality control and the improvement of monitoring procedures was proposed by using the hydrological model to simulate different scenarios. The GeoCIRC-model-based OOD allowed the prediction of the concentrations of heavy metals with minimal input data. Also, various heavy metals could be numerically treated simultaneously because the OOD increases the model's flexibility to allow the handling of many transportable materials. Therefore, the GeoCIRC model is a powerful tool for the monitoring of environmental contamination in rivers by various heavy metals.

High-capacity electrode materials for rechargeable lithium batteries: Li3NbO4-based system with cation-disordered rocksalt structure.

Rechargeable lithium batteries have rapidly risen to prominence as fundamental devices for green and sustainable energy development. Lithium batteries are now used as power sources for electric vehicles. However, materials innovations are still needed to satisfy the growing demand for increasing energy density of lithium batteries. In the past decade, lithium-excess compounds, Li2MeO3 (Me = Mn(4+), Ru(4+), etc.), have been extensively studied as high-capacity positive electrode materials. Although the origin as the high reversible capacity has been a debatable subject for a long time, recently it has been confirmed that charge compensation is partly achieved by solid-state redox of nonmetal anions (i.e., oxide ions), coupled with solid-state redox of transition metals, which is the basic theory used for classic lithium insertion materials, such as LiMeO2 (Me = Co(3+), Ni(3+), etc.). Herein, as a compound with further excess lithium contents, a cation-ordered rocksalt phase with lithium and pentavalent niobium ions, Li3NbO4, is first examined as the host structure of a new series of high-capacity positive electrode materials for rechargeable lithium batteries. Approximately 300 mAh ⋅ g(-1) of high-reversible capacity at 50 °C is experimentally observed, which partly originates from charge compensation by solid-state redox of oxide ions. It is proposed that such a charge compensation process by oxide ions is effectively stabilized by the presence of electrochemically inactive niobium ions. These results will contribute to the development of a new class of high-capacity electrode materials, potentially with further lithium enrichment (and fewer transition metals) in the close-packed framework structure with oxide ions.

Leptospirosis in the Tohoku region: re-emerging infectious disease.

Leptospirosis is a zoonotic and disaster-related infectious disease. It is mainly endemic in subtropical or tropical countries and has not been reported since 2009 in the Tohoku region (northern Japan), including the Yamagata and Miyagi Prefectures. However, we experienced four patients with leptospirosis in the Tohoku region from 2012 to 2014; three patients (#1-3) live in the agricultural areas of the Yamagata Prefecture and one patient (#4) was a visitor to the Miyagi Prefecture. Patient 1 (81-year-old female) is a villager, with a rat bite, while Patient 2 (77-year-old male) and Patient 3 (84-year-old female) are farmers and were infected probably during agriculture work. Patient 4 (40-year-old male US citizen) was infected while traveling in Thailand. They had chief complaint of fever, headache, and myalgia and showed manifestations of hyperbilirubinemia (mean, 4.35 mg/dL), thrombocytopenia and acute kidney injury (AKI). All patients were diagnosed by polymerase chain reaction using blood and/or urine samples and a microscopic agglutination test for the anti-Leptospira antibody. All the patients were treated with infused antibiotics, including minocycline. The patients underwent hemodialysis due to severe AKI (mean serum creatinine, 4.44 mg/dL), except for Patient 2 with the normal serum creatinine level (1.12 mg/dL). All the patients recovered and were discharged. The presence of the three patients in the Yamagata Prefecture implies that leptospirosis does re-emerge in the Tohoku region. Therefore, careful survey of the pathogen is necessary for febrile patients with AKI who engage in agriculture or have a recent history of travelling in subtropical or tropical countries.

Effect of allopurinol on cardiovascular incidence among hypertensive nephropathy patients: the Gonryo study.

BACKGROUND: The present study aimed to clarify the beneficial effect of allopurinol on cardiovascular morbidity and mortality in a cohort of hypertensive nephropathy patients with impaired kidney function. METHODS: One hundred and seventy-eight patients diagnosed with hypertensive nephropathy and presenting with impaired kidney function (estimated glomerular filtration rate <45 mL/min/1.73 m(2)) were recruited from nephrology clinics. Oral allopurinol was prescribed in 67 of these patients. The effects of allopurinol use on the development of cardiovascular disease (i.e. ischemic heart disease, congestive heart failure, and stroke) and all-cause death was analyzed using the Cox proportional hazard model. RESULTS: During the follow-up of 18.4 months (mean), 28 primary events occurred. Basal use of allopurinol was a significant beneficial factor (hazard ratio = 0.342, p = 0.0434, standard error = 0.53058) after adjusting for confounding factors. CONCLUSION: The use of allopurinol in hypertensive subjects with impaired kidney function appears to be beneficial in preventing cardiovascular morbidity and all-cause mortality, indicating that this xanthine oxidase inhibitor protects the vascular system, at least in this specific group.

Ideal water temperature environment for giant Marimo (Aegagropila linnaei) in Lake Akan, Japan.

Aegagropila linnaei is a filamentous green algal species that often forms beautiful spherical shapes called "lake balls" or "Marimo". A. linnaei were once globally distributed around the world, but the population has been declining for several decades. Lake Akan, in Japan, is now the only lake in the world with a colony of giant Marimo (over 20 cm in diameter). Here we show the net growth rate of Marino resulting from photosynthesis and decomposition based on laboratory experiments, MRI analysis, and quantitative element analysis, which show the decomposition rate, the maximum annual Marimo diametric growth rate, and the carbon-to-nitrogen ratio, respectively. We found an explicit dependence of the decomposition rate of Marimo on the cumulative water temperature, with a threshold of 7 °C. MRI analysis showed a high correlation among a Marimo's diameter, surface thickness, and annual diametric growth rate. Moreover, the C/N ratio was high in the exterior side of the surface thickness, indicating that this layer is the main growth area for photosynthesis. These results suggest that the central cavity and the surface thickness represent the change in the growth environment such as water temperature and light intensity. Between the 1980s and the present, Between the 1980s and the present, the cumulative water temperature has increased from about 1250 to about 1600 °C-days. Therefore, the maximum surface thickness has decreased by approximately 1 cm, as estimated by water temperature records and annual diametric growth rates10. As a measure to preserve preferable conditions for colonies of giant Marimo in the face of global warming, the flow of low-temperature river water into Marimo colonies should be protected.

Carbon dioxide uptake in a eutrophic stratified reservoir: Freshwater carbon sequestration potential.

Carbon capture and storage due to photosynthesis activities has been proposed as a carbon sink to mitigate climate change. To enhance such mitigation, previous studies have shown that freshwater lakes should be included in the carbon sink, since they may capture as much carbon as coastal areas. In eutrophic freshwater lakes, there is uncertainty about whether the equilibrium equation can estimate the partial pressure of carbon dioxide (pCO2), owing to the presence of photosynthesis due to phytoplankton, and pH measurement error in freshwater fluid. Thus, this study investigated the applicability of the equilibrium equation and revealed the need to modify it. The modified equilibrium equation was successfully applied to reproduce pCO2 based on total alkalinity and pH through field observations. In addition, pCO2 at the water surface was lower than the atmospheric partial pressure of carbon dioxide due to photosynthesis by phytoplankton during strong stratification. The stratification effect on low pCO2 was verified by using the Net Ecosystem Production (NEP) model, and a submerged freshwater plants such as Potamogeton malaianus were found to have high potential for dissolved inorganic carbon (DIC) sequestration in a freshwater lake. These results should provide a starting point toward more sophisticated methods to investigate the effect of freshwater carbon on DIC uptake in freshwater stratified eutrophic lakes.

Haemolysin E- and enterohaemolysin-derived haemolytic activity of O55/O157 strains and other Escherichia coli lineages.

Among three haemolysins identified thus far in Escherichia coli, alpha-haemolysin (HlyA) is encoded on the pathogenicity islands of extraintestinal pathogenic strains, while enterohaemolysin (EhxA) is encoded on the virulence plasmids of enterohaemorrhagic E. coli (EHEC) strains. In contrast, the gene for haemolysin E (HlyE) is located on the E. coli chromosome backbone and is therefore widely distributed among E. coli strains. However, because hlyE gene expression is repressed by the H-NS protein and because the gene has been disrupted in many strains, its haemolytic activity cannot be detected in wild-type strains by routine screening on blood agar plates. In this study, we found that the HlyE-derived haemolytic activity of enteropathogenic E. coli (EPEC) O55 : H7 can be detected after anaerobic cultivation on a washed blood agar plate (EHX plate) that is used to detect the production of EhxA. We also found that the haemolytic activity of EHEC O157 : H7 observed on EHX plates under aerobic and anaerobic growth conditions is derived from EhxA and HlyE, respectively; this differential expression of the two haemolysins occurs at the transcriptional level. Our analysis of 60 E. coli strains of various pathotypes and phylogenies for their repertoires of haemolysin genes, haemolytic phenotypes and hlyE gene sequences revealed that HlyE activity can generally be detected on EHX plates under anaerobic growth conditions if the gene is intact. Furthermore, our results indicate that hlyE gene inactivation occurred in three of the five E. coli lineages (phylogroups A, B1 and B2), which demonstrates phylogroup-specific gene disruption patterns.

Inference of the impact of insertion sequence (IS) elements on bacterial genome diversification through analysis of small-size structural polymorphisms in Escherichia coli O157 genomes.

Mobile genetic elements play important roles in the evolution and diversification of bacterial genomes. In enterohemorrhagic Escherichia coli O157, a major factor that affects genomic diversity is prophages, which generate most of the large-size structural polymorphisms (LSSPs) observed in O157 genomes. Here, we describe the results of a systematic analysis of numerous small-size structural polymorphisms (SSSPs) that were detected by comparing the genomes of eight clinical isolates with a sequenced strain, O157 Sakai. Most of the SSSPs were generated by genetic events associated with only two insertion sequence (IS) elements, IS629 and ISEc8, and a number of genes that were inactivated or deleted by these events were identified. Simple excisions of IS629 and small deletions (footprints) formed by the excision of IS629, both of which are rarely described in bacteria, were also detected. In addition, the distribution of IS elements was highly biased toward prophages, prophage-like integrative elements, and plasmids. Based on these and our previous results, we conclude that, in addition to prophages, these two IS elements are major contributors to the genomic diversification of O157 strains and that LSSPs have been generated mainly by bacteriophages and SSSPs by IS elements. We also suggest that IS elements possibly play a role in the inactivation and immobilization of incoming phages and plasmids. Taken together, our results reveal the true impact of IS elements on the diversification of bacterial genomes and highlight their novel role in genome evolution.

Comparative genomics reveal the mechanism of the parallel evolution of O157 and non-O157 enterohemorrhagic Escherichia coli.

Among the various pathogenic Escherichia coli strains, enterohemorrhagic E. coli (EHEC) is the most devastating. Although serotype O157:H7 strains are the most prevalent, strains of different serotypes also possess similar pathogenic potential. Here, we present the results of a genomic comparison between EHECs of serotype O157, O26, O111, and O103, as well as 21 other, fully sequenced E. coli/Shigella strains. All EHECs have much larger genomes (5.5-5.9 Mb) than the other strains and contain surprisingly large numbers of prophages and integrative elements (IEs). The gene contents of the 4 EHECs do not follow the phylogenetic relationships of the strains, and they share virulence genes for Shiga toxins and many other factors. We found many lambdoid phages, IEs, and virulence plasmids that carry the same or similar virulence genes but have distinct evolutionary histories, indicating that independent acquisition of these mobile genetic elements has driven the evolution of each EHEC. Particularly interesting is the evolution of the type III secretion system (T3SS). We found that the T3SS of EHECs is composed of genes that were introduced by 3 different types of genetic elements: an IE referred to as the locus of enterocyte effacement, which encodes a central part of the T3SS; SpLE3-like IEs; and lambdoid phages carrying numerous T3SS effector genes and other T3SS-related genes. Our data demonstrate how E. coli strains of different phylogenies can independently evolve into EHECs, providing unique insights into the mechanisms underlying the parallel evolution of complex virulence systems in bacteria.

Diffusive methane burst during a blue tide, wind-driven event in a meromictic lake.

Strong stratification has formed in Lake Abashiri, a typical meromictic lake in Hokkaido, in the subarctic zone in Japan. When the anoxic water of the lower layer is upwelled to the surface by a strong wind, fish and corbicula clams die due to a lack of dissolved oxygen. This event is called as blue tide. It was observed that the dissolved methane in the lake decreased more than 100 t after the blue tide which occurred in 2008. This is the discovery of the phenomenon that a large quantity of methane diffuses to the atmosphere caused by upwelling of anoxic water which contains dissolved methane. We named the event as "methane burst". It is also the first report that the wind-driven upwelling is reproduced using a numerical analysis code and the methane burst is analyzed. During this blue tide, the methane flux was approximately 170 times greater than usual.

Effects of vorticity on solitary waves.

The vorticity effect on solitary wave profiles has not been solved experimentally; previous studies theoretically and numerically showed that when a solitary wave progressed in the positive direction, the effective wavelength of a solitary wave with positive vorticity increased. Using laboratory experiments and fully nonlinear numerical simulations, we here show that the effective wavelength is extended more when positive vorticity is given to a progressive wave in the positive direction. We further show that the total energy increases with increasing positive vorticity, demonstrating that a wave with positive vorticity propagates with less attenuation and lasts longer than a solitary wave with no vorticity. We anticipate that our outcomes will provide a starting point for more sophisticated methods to investigate the effect of vorticity on solitary waves in laboratory experiments and numerical simulations.

Cleft Sign and Bone Marrow Edema of the Pubic Symphysis Are Associated With Sports and Bony Morphology in Patients With Femoroacetabular Impingement and Labral Tears.

BACKGROUND: The cleft sign (CS) and bone marrow edema (BME) are considered magnetic resonance imaging (MRI) findings signifying a pubic pathology, which is associated with groin pain; however, their relationship with bony morphology related to femoroacetabular impingement (FAI) has not been established. PURPOSE: To investigate the prevalence of CS and BME in symptomatic patients with acetabular labral tears and assess their possible association with bone morphology and sport-specific activities. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: This study enrolled 418 patients (469 hips) undergoing hip arthroscopic surgery for labral tears. Also included were patients with labral tears in the setting of either hip dysplasia or borderline hip dysplasia who were undergoing endoscopic shelf acetabuloplasty combined with hip arthroscopic labral repair, cam osteoplasty, and capsular plication. All patients were screened for superior CS (SCS), inferior CS (ICS), and BME of the ipsilateral side of the pubis using 3-T MRI. We measured the following angles: lateral center edge (LCE), Sharp, Tönnis, vertical-central-anterior, and alpha. Then, we evaluated the relationship between patient characteristics and abnormal findings on MRI scans (preoperatively vs 1 year postoperatively). RESULTS: An overall 397 hips were included: 200 in men and 197 in women (mean ± SD age, 35.3 ± 16.0 years). There were hips in 214 athletes (53.9%) and hips in 183 nonathletes (46.1%). MRI findings revealed SCS, ICS, and BME in 18 (4.5%), 13 (3.3%), and 34 hips (8.6%), respectively. Abnormal MRI findings at the pubis were seen more often in athletes than nonathletes (23.8% vs 3.3%), and contact sports athletes had the most frequent abnormalities. There was no SCS in patients with an LCE angle <22°. SCS was more frequently seen in those who had an alpha angle ≥71°. More than 60% of abnormal findings at the pubis diminished after arthroscopic surgery that included FAI correction and labral repair. CONCLUSION: In patients with labral tears, CS and BME were seen more frequently in athletes versus nonathletes, especially contact athletes with FAI-related bony abnormalities. More than 60% of abnormal MRI pubis findings resolved after arthroscopic treatment of FAI.

The impacts of the hydraulic retention effect and typhoon disturbance on the carbon flux in shallow subtropical mountain lakes.

A typhoon is extreme weather that flushes terrestrial carbon (C) loads and temporally mixes the entire water columns of lakes in subtropical regions. A C flux varies based on the trophic level associated with the ecological cycle related to hydraulic retention time (residence time). Herein, we sought to clarify how the hydraulic retention time and the disturbance from a typhoon affect the C flux regimes in two subtropical mountain lakes in a humid region of Taiwan with different trophic levels-oligotrophic and mesotrophic. We investigated the meteorological data and vertical profiles of the water temperature, dissolved inorganic carbon (DIC), dissolved organic C (DOC), and chlorophyll a (Chl. a) during the pre-typhoon period (April-July), during the typhoon period (August-November), and the post-typhoon period (December-March) for five years (2009-2010 and 2015-2017). We applied a three-dimensional environmental model (Fantom) to investigate the hydraulic retention effect on the net ecosystem production (NEP) using the residence time in stratified lakes. The results demonstrate that typhoon-induced mixing associated with the hydraulic retention effect plays one of the critical roles in controlling the NEP and C flux in shallow subtropical lakes.

Effects of oyster aquaculture on carbon capture and removal in a tropical mangrove lagoon in southwestern Taiwan.

Blue carbon ecosystems (BCEs) are a promising resource for the mitigation of global warming; however, climate spectrums and anthropogenic activities could influence the fragile balance of BCEs as carbon sinks or sources. We assess how oyster farming affects dissolved inorganic carbon (DIC) and total alkalinity (TA) on CO2 fluxes in a mangrove-dominated lagoon. Water physical, chemical and biological parameters were recorded by in-situ buoys within the lagoon and at its inflow. Structural equation modeling was adopted to clarify the factors/processes controlling the partial pressure of CO2 (pCO2). A three-dimensional environmental model followed by a conceptual DIC model was used to quantify the spatiotemporal patterns of capture and release of DIC and TA by oyster production. The results showed that 49% of TA and DIC released from mangroves was depleted by oyster shell formation. DIC was reduced by algal photosynthesis and algal was served as a food source supporting oyster production. Annual oyster production through phytoplankton photosynthesis accounted for 11% of the atmosphere carbon inflows, suggesting that oyster production served as a significant atmospheric/terrestrial carbon sink in the lagoon. The results indicate that mangroves benefit local oyster production by acting as an important source of DIC and TA, and that the oyster aquaculture contributed to carbon capture in a mangrove-dominated lagoon ecosystem.

The genome of Erysipelothrix rhusiopathiae, the causative agent of swine erysipelas, reveals new insights into the evolution of firmicutes and the organism's intracellular adaptations.

Erysipelothrix rhusiopathiae is a Gram-positive bacterium that represents a new class, Erysipelotrichia, in the phylum Firmicutes. The organism is a facultative intracellular pathogen that causes swine erysipelas, as well as a variety of diseases in many animals. Here, we report the first complete genome sequence analysis of a member of the class Erysipelotrichia. The E. rhusiopathiae genome (1,787,941 bp) is one of the smallest genomes in the phylum Firmicutes. Phylogenetic analyses based on the 16S rRNA gene and 31 universal protein families suggest that E. rhusiopathiae is phylogenetically close to Mollicutes, which comprises Mycoplasma species. Genome analyses show that the overall features of the E. rhusiopathiae genome are similar to those of other Gram-positive bacteria; it possesses a complete set of peptidoglycan biosynthesis genes, two-component regulatory systems, and various cell wall-associated virulence factors, including a capsule and adhesins. However, it lacks many orthologous genes for the biosynthesis of wall teichoic acids (WTA) and lipoteichoic acids (LTA) and the dltABCD operon, which is responsible for d-alanine incorporation into WTA and LTA, suggesting that the organism has an atypical cell wall. In addition, like Mollicutes, its genome shows a complete loss of fatty acid biosynthesis pathways and lacks the genes for the biosynthesis of many amino acids, cofactors, and vitamins, indicating reductive genome evolution. The genome encodes nine antioxidant factors and nine phospholipases, which facilitate intracellular survival in phagocytes. Thus, the E. rhusiopathiae genome represents evolutionary traits of both Firmicutes and Mollicutes and provides new insights into its evolutionary adaptations for intracellular survival.

The defective prophage pool of Escherichia coli O157: prophage-prophage interactions potentiate horizontal transfer of virulence determinants.

Bacteriophages are major genetic factors promoting horizontal gene transfer (HGT) between bacteria. Their roles in dynamic bacterial genome evolution have been increasingly highlighted by the fact that many sequenced bacterial genomes contain multiple prophages carrying a wide range of genes. Enterohemorrhagic Escherichia coli O157 is the most striking case. A sequenced strain (O157 Sakai) possesses 18 prophages (Sp1-Sp18) that encode numerous genes related to O157 virulence, including those for two potent cytotoxins, Shiga toxins (Stx) 1 and 2. However, most of these prophages appeared to contain multiple genetic defects. To understand whether these defective prophages have the potential to act as mobile genetic elements to spread virulence determinants, we looked closely at the Sp1-Sp18 sequences, defined the genetic defects of each Sp, and then systematically analyzed all Sps for their biological activities. We show that many of the defective prophages, including the Stx1 phage, are inducible and released from O157 cells as particulate DNA. In fact, some prophages can even be transferred to other E. coli strains. We also show that new Stx1 phages are generated by recombination between the Stx1 and Stx2 phage genomes. The results indicate that these defective prophages are not simply genetic remnants generated in the course of O157 evolution, but rather genetic elements with a high potential for disseminating virulence-related genes and other genetic traits to other bacteria. We speculate that recombination and various other types of inter-prophage interactions in the O157 prophage pool potentiate such activities. Our data provide new insights into the potential activities of the defective prophages embedded in bacterial genomes and lead to the formulation of a novel concept of inter-prophage interactions in defective prophage communities.

Intake of water with high levels of dissolved hydrogen (H2) suppresses ischemia-induced cardio-renal injury in Dahl salt-sensitive rats.

BACKGROUND: Hydrogen (H(2)) reportedly produces an antioxidative effect by quenching cytotoxic oxygen radicals. We studied the biological effects of water with dissolved H(2) on ischemia-induced cardio-renal injury in a rat model of chronic kidney disease (CKD). METHODS: Dahl salt-sensitive rats (7 weeks old) were allowed ad libitum drinking of filtered water (FW: dissolved H(2), 0.00 ± 0.00 mg/L) or water with dissolved H(2) produced by electrolysis (EW: dissolved H(2), 0.35 ± 0.03 mg/L) for up to 6 weeks on a 0.5% salt diet. The rats then underwent ischemic reperfusion (I/R) of one kidney and were killed a week later for investigation of the contralateral kidney and the heart. RESULTS: In the rats given FW, unilateral kidney I/R induced significant increases in plasma monocyte chemoattractant protein-1, methylglyoxal and blood urea nitrogen. Histologically, significant increases were found in glomerular adhesion, cardiac fibrosis, number of ED-1 (CD68)-positive cells and nitrotyrosine staining in the contralateral kidney and the heart. In rats given EW, those findings were significantly ameliorated and there were significant histological differences between rats given FW and those given EW. CONCLUSION: Consumption of EW by ad libitum drinking has the potential to ameliorate ischemia-induced cardio-renal injury in CKD model rats. This indicates a novel strategy of applying H(2) produced by water electrolysis technology for the prevention of CKD cardio-renal syndrome.