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The effectiveness of antibiotics against bacterial infections has been declining due to the emergence of resistance. Precisely understanding the response of bacteria to antibiotics is critical to maximizing antibiotic-induced bacterial eradication while minimizing the emergence of antibiotic resistance. Cell-to-cell heterogeneity in antibiotic susceptibility is observed across various bacterial species for a wide range of antibiotics. Heterogeneity in antibiotic susceptibility is not always due to the genetic differences. Rather, it can be caused by non-genetic mechanisms such as stochastic gene expression and biased partitioning upon cell division. Heterogeneous susceptibility leads to the stochastic growth and death of individual cells and stochastic fluctuations in population size. These fluctuations have important implications for the eradication of bacterial populations and the emergence of genotypic resistance.

Summary Direct cardiac reprogramming holds great potential for regenerative medicine. However, it remains inefficient, and induced cardiomyocytes (iCMs) generated in vitro are less mature than those in vivo, suggesting that undefined extrinsic factors may regulate cardiac reprogramming. Previous in vitro studies mainly used hard polystyrene dishes, yet the effect of substrate rigidity on cardiac reprogramming remains unclear. Thus, we developed a Matrigel-based hydrogel culture system to determine the roles of matrix stiffness and mechanotransduction in cardiac reprogramming. We found that soft matrix comparable with native myocardium promoted the efficiency and quality of cardiac reprogramming. Mechanistically, soft matrix enhanced cardiac reprogramming via inhibition of integrin, Rho/ROCK, actomyosin, and YAP/TAZ signaling and suppression of fibroblast programs, which were activated on rigid substrates. Soft substrate further enhanced cardiac reprogramming with Sendai virus vectors via YAP/TAZ suppression, increasing the reprogramming efficiency up to ∼15%. Thus, mechanotransduction could provide new targets for improving cardiac reprogramming., Graphical Abstract, Highlights • Hydrogel culture reveals the role of mechanotransduction in cardiac reprogramming • Soft ECM comparable with native myocardium promotes cardiac reprogramming • Soft ECM promotes cardiac reprogramming via YAP/TAZ/fibroblast signaling inhibition • Soft ECM promotes Sendai virus vector-mediated cardiac reprogramming, In this article, Ieda and colleagues showed that a soft matrix, which is comparable with native myocardium, efficiently promoted cardiac reprogramming. This soft matrix enhanced cardiac reprogramming via inhibition of integrin, Rho/ROCK, actomyosin, and YAP/TAZ signaling and subsequent suppression of fibroblast programs, which were activated on conventional rigid substrates, thus demonstrating that mechanotransduction plays a critical role in cardiac reprogramming.

Background Pulmonary hypertension (PH) is traditionally defined as a resting mean pulmonary artery pressure (mPAP) of ≥25 mmHg, while mPAP in the range of 21 to 24 mmHg is recognized as “borderline PH.” Interstitial lung disease (ILD) is complicated by the development of PH, which is known to be linked with exercise intolerance and a poor prognosis. Even though it has recently been recommended that PH is redefined as a mPAP of > 20 mmHg, little is known about the clinical significance of borderline PH in ILD. We evaluated whether borderline PH has an impact on the exercise capacity, risk of acute exacerbation (AE), and mortality in patients with ILD. Methods A total of 80 patients with ILD who underwent right heart catheterization (RHC) between November 2013 and October 2016 were included. The patients were divided into 3 groups according to the mPAP values: mPAP ≤20 mmHg (No-PH group; n = 56), 20

Adult hearts have limited regenerative capacity. Hence, after acute myocardial infarction (MI), dead myocardial tissues are digested by immune cells and replaced by fibrosis, leading to ventricular remodeling and heart failure at the chronic stage. Direct reprogramming of the cardiac fibroblasts (CFs) into induced cardiomyocytes (iCMs) with cardiac transcription factors, including Gata4, Mef2c, and Tbx5 (GMT), may have significant potential for cardiac repair. Sendai virus (SeV) vectors expressing GMT have been reported to reprogram the mouse cardiac fibroblasts into iCMs without any risk of insertional mutagenesis. In vivo reprogramming improved the cardiac function after acute MI in immunodeficient mice. However, it is unknown whether the newly generated iCMs could exist in infarct hearts for a prolonged period and SeV-GMT can improve cardiac function after MI at the chronic stage in immunocompetent mice. Here, we show that SeV vectors efficiently infect CFs in vivo and reprogram them into iCMs, which existed for at least four weeks after MI, in fibroblast-linage tracing mice. Moreover, SeV-GMT improved cardiac function and reduced fibrosis and collagen I expression at 12 weeks after MI in immunocompetent mice. Thus, direct cardiac reprogramming with SeV vectors could be a promising therapy for MI.

Hintergrund: Die exzessive Inhalation von Aluminiumstaub führt gelegentlich zu einer überwiegend die Oberlappen betreffenden Lungenfibrose, die einer idiopathischen pleuroparenchymalen Fibroelastose (IPPFE) ähnelt und bei der es sich den Annahmen zufolge um eine sekundäre PPFE handelt. Fallbericht: Ein 67-jähriger Mann, der 50 Jahre lang in einem aluminiumverarbeitenden Unternehmen gearbeitet hatte, stellte sich mit Belastungsdyspnoe in unserer Klinik vor. Die Computertomographie (CT) des Thorax zeigte eine bilaterale dichte subpleurale Konsolidierung in den oberen und mittleren Lungenfeldern entsprechend einer IPPFE; eine etwaige sekundäre PPFE im Zusammenhang mit einer Aluminose wurde jedoch nicht ausgeschlossen. Aufgrund des kritischen Zustands des Patienten erfolgten eine transbronchiale Lungenbiopsie (TBLB) anstatt einer chirurgischen Lungenbiopsie sowie eine Elementaranalyse der entnommenen Gewebeprobe. Da die mittels TBLB gewonnene Probe bedauerlicherweise kein Alveolargewebe enthielt, konnte die Diagnose PPFE nicht pathologisch gesichert werden. Die radiologischen Befunde sprachen jedoch stark für eine PPFE. In der Elementaranalyse wurden hohe Mengen an Aluminium in den Bronchiolarwänden nachgewiesen, so dass die Diagnose einer Aluminose der Atemwege mit wahrscheinlich sekundärer PPFE infolge Aluminiumexposition gestellt wurde. Schlussfolgerungen: Eine TBLB mit Elementaranalyse kann zur Abgrenzung der idiopathischen PPFE von sekundären Ursachen bei staubbedingten Erkrankungen wie Aluminose hilfreich sein. Der vorliegende Fall zeigt, dass die Inhalation von Aluminium eine sekundäre PPFE verursachen kann; ein besonderes Augenmerk sollte auf die Vermeidung einer weiteren Exposition gelegt werden.

Pseudomonas aeruginosa biofilm infections are difficult to treat with antibiotic therapy in part because the biofilms contain subpopulations of dormant antibiotic-tolerant cells. The dormant cells can repopulate the biofilms following alleviation of antibiotic treatments. While dormant, the bacteria must maintain cellular integrity, including ribosome abundance, to reinitiate the de novo protein synthesis required for resuscitation. Here, we demonstrate that the P. aeruginosa gene PA4463 [hibernation promoting factor (HPF)], but not the ribosome modulation factor (PA3049), is required for ribosomal RNA preservation during prolonged nutrient starvation conditions. Single-cell–level studies using fluorescence in situ hybridization (FISH) and growth in microfluidic drops demonstrate that, in the absence of hpf, the rRNA abundances of starved cells decrease to levels that cause them to lose their ability to resuscitate from starvation, leaving intact nondividing cells. P. aeruginosa defective in the stringent response also had reduced ability to resuscitate from dormancy. However, FISH analysis of the starved stringent response mutant showed a bimodal response where the individual cells contained either abundant or low ribosome content, compared with the wild-type strain. The results indicate that ribosome maintenance is key for maintaining the ability of P. aeruginosa to resuscitate from starvation-induced dormancy and that HPF is the major factor associated with P. aeruginosa ribosome preservation.

Background Marfan Syndrome (MFS) is a heritable connective tissue disorder with a high degree of clinical variability including respiratory diseases; a rare case of MFS with massive intrathoracic bleeding has been reported recently. Case presentation A 32-year-old man who had been diagnosed with MFS underwent a Bentall operation with artificial valve replacement for aortic dissection and regurgitation of an aortic valve in 2012. Warfarin was started postoperatively, and the dosage was gradually increased until 2017, when the patient was transported to our hospital due to sudden massive haemoptysis. Computed tomography (CT) with a maximum intensity projection (MIP) revealed several giant pulmonary cysts with fluid levels in the apex of the right lung with an abnormal vessel from the right subclavian artery. Transcatheter arterial embolization was performed with angiography and haemostasis was achieved, which suggested that the bleeding vessel was the lateral thoracic artery (LTA) branch. CT taken before the incident indicated thickening of the cystic wall adjacent to the thorax; therefore, it was postulated that the bleeding originated from fragile anastomoses between the LTA and pulmonary or bronchial arteries. It appears that the vessels exhibited inflammation that began postoperatively, which extended to the cysts. Conclusion We experienced a case of MFS with massive haemoptysis from the right LTA. We have to be aware of the possibility that massive haemoptysis could be induced in MFS with inflamed pulmonary cysts.

Background: Excessive inhalation of aluminium powder occasionally results in upper lobe predominant lung fibrosis, which is similar to idiopathic pleuroparenchymal fibroelastosis (IPPFE) and has been suggested to be secondary PPFE. Case presentation: A 67-year-old man who had worked in an aluminum-processing factory for 50 years visited our hospital complaining of exertional dyspnea. Chest computed tomography (CT) showed bilateral dense sub-pleural consolidation in the upper and middle lung fields, which was consistent with IPPFE; however, the possibility of secondary PPFE associated with aluminosis was not ruled out. Considering the patient’s critical condition, trans-bronchial lung biopsy (TBLB) rather than surgical lung biopsy was performed, with elemental analysis of the biopsied specimen. Unfortunately, the specimen obtained by TBLB did not contain alveolar tissue; therefore, pathological diagnosis of PPFE was not possible. However, radiographic findings were highly suggestive of PPFE. On elemental analysis, excessive amounts of aluminum were detected in the bronchiolar walls, establishing a diagnosis of airway aluminosis with likely secondary PPFE resulting from aluminium exposure. Conclusions: TBLB with elemental analysis might be useful in differentiating idiopathic PPFE from secondary causes in dust inhalation related disease, such as aluminosis. This case indicated that inhalation of aluminium might cause secondary PPFE, with attention needing to be paid to avoid further exposure.

Background: Pulmonary hypertension (PH) is defined by a resting mean pulmonary artery pressure (mPAP) ≥ 25 mmHg, on the other hand, the term of mPAP ranging from 21 to 24 mmHg is recognized as “borderline PH”. However, little is known about the clinical importance of borderline PH in interstitial lung disease (ILD). Aims: To evaluate whether borderline PH has an impact on the exercise capacity and the risk of acute exacerbation (AE) in patients with ILD. Methods: Between November 2013 and October 2016, 80 patients with ILD (23 IPF) that underwent right heart catheterization were included. The patients were divided into 3 groups: mPAP ≤ 20mmHg (No-PH group; n = 56), 21 ≤ mPAP ≤ 24mmHg (Bo-PH group; n = 18) and mPAP ≥ 25mmHg (PH group; n = 6). Patients’ characteristics, hemodynamics, 6MWT data, and 1-year incidence of AE were collected. Results: There were no significant differences among 3 groups in patients’ characteristics including pulmonary function. However, both Bo-PH and PH groups had significantly lower 6-min walk distance (p Conclusions: The current study shows that borderline PH is associated with exercise intolerance and increased risk for acute exacerbation in patients with ILD. These results suggest that the presence of borderline PH should be considered the pulmonary vascular disorder in patients with ILD.

Cytolethal distending toxin B (cdtB) is a conserved virulence factor in Salmonella enterica serovar Typhi. Here we report the presence and functionality of cdtB in some nontyphoidal Salmonella (NTS) serovars, including Salmonella Javiana (cdtB+wt S. Javiana), isolated from imported food. To understand the role of cdtB in NTS serovars, a deletion mutant (cdtB(-)ΔS. Javiana) was constructed. Macrophages were infected with cdtB+wt S. Javiana (wild type), cdtB(-)Δ S. Javiana (mutant), and cdtB-negative NTS serovar (S. Typhimurium). Cytotoxic activity and transcription level of genes involved in cell death (apoptosis, autophagy, and necrosis) were assessed in infected macrophages. The cdtB+wt S. Javiana caused cellular distension as well as high degree of vacuolization and presence of the autophagosome marker LC3 in infected macrophages as compared with cdtB(-)ΔS. Javiana. The mRNA expression of genes involved in the induction of autophagy in response to toxin (Esr1 and Pik3C3) and coregulators of autophagy and apoptosis (Bax and Cyld) were significantly upregulated in cdtB(+)wt S. Javiana-infected macrophages. As autophagy destroys internalized pathogens in addition to the infected cell, it may reduce the spread of infection.

Dissemination of plasmid-mediated quinolone resistance among pathogenic bacteria is a concern for public health because of decreased sensitivity to fluoroquinolones and increased potentials to develop high fluoroquinolone resistance. Two qnrS1 -positive isolates of Salmonella enterica Corvallis (468) and Typhimurium (484) from imported seafood (Thailand and Vietnam) were tested for quinolone sensitivity using disk agar diffusion and the Sensititre® system. The presence of qnr genes, qnr carrying plasmids, and mutations in the quinolone resistance determining regions were also determined. Minimal inhibitory concentrations of nalidixic acid for isolates 468 and 484 were 8 and 16 µg mL−1, respectively, and those of ciprofloxacin were 1 and 2 µg mL−1, respectively. Disk agar diffusion indicated that isolate 468 was moderately resistant to moxifloxacin, and isolate 484 was resistant to moxifloxacin and moderately resistant to norfloxacin. Isolates 468 and 484 carried a mutation on parC , but not on gyrA , gyrB , or parE . Sequences of qnrS1 -carrying plasmids from isolates 468 and 484, sized 10 039 and 10 047 bp, were nearly identical (> 99% similarity) to each other and to published sequences of plasmids from clinical isolates of Salmonella Typhimurium isolated in the United Kingdom and Taiwan, indicating a dissemination of qnrS1 -carrying plasmids among different serovars of Salmonella from geographically separated sources. This is the first complete sequence of a qnrS1 -carrying plasmid from imported seafood isolate of S. enterica .

血液透析導入時にヘパリン起因性血小板減少症（HIT）を発症し，その後ヘパリンの再投与に成功した症例を経験したので報告する．症例は68歳女性．以前より慢性腎不全を指摘されており，近医に通院していた．末期腎不全にて当院紹介受診し，血液透析導入目的で入院した．入院後，内シャント造設術を施行した．シャント血流は良好であった．透析の抗凝固剤として未分画ヘパリンを使用した．第1回透析から第3回透析までは著変なく施行できた．第4回，第5回透析では若干の静脈圧の上昇を認めたが，明らかな回路内凝固は認めなかった．第6回透析では静脈圧の上昇とチャンバー・ダイアライザーの凝血を認めた．ヘパリン量の不足が原因と考え，ヘパリンの増量を行ったが改善を認めなかった．透析前後で血小板数の減少があり，HITを疑い，抗血小板第4因子/ヘパリン複合体抗体（HIT抗体）を測定した．抗凝固剤をメシル酸ナファモスタットに変更後，回路内凝固と血小板減少は改善した．HIT抗体が陽性であったため，HITと診断し，抗凝固剤をアルガトロバンに変更し，開始時10mg，持続25mg/時で血液透析を行った．以降は回路内凝固を認めず，また，血小板減少も認めなかった．その間，血栓症の合併はなかった．経時的にHIT抗体価を測定し，HIT抗体価が陰性化したことを確認した．ヘパリンの再投与を試みたところ，回路内凝固や血小板減少を認めることなく，血液透析を施行することができた．HIT抗体価の再上昇もなく，現在に至っている．

Pseudomonas aeruginosa is an opportunistic human pathogen that causes severe, life-threatening infections in patients with cystic fibrosis (CF), endocarditis, wounds, or artificial implants. During CF pulmonary infections, P. aeruginosa often encounters environments where the levels of calcium (Ca 2+ ) are elevated. Previously, we showed that P. aeruginosa responds to externally added Ca 2+ through enhanced biofilm formation, increased production of several secreted virulence factors, and by developing a transient increase in the intracellular Ca 2+ level, followed by its removal to the basal submicromolar level. However, the molecular mechanisms responsible for regulating Ca 2+ -induced virulence factor production and Ca 2+ homeostasis are not known. Here, we characterized the genome-wide transcriptional response of P. aeruginosa to elevated [Ca 2+ ] in both planktonic cultures and biofilms. Among the genes induced by CaCl 2 in strain PAO1 was an operon containing the two-component regulator PA2656-PA2657 (here called carS and carR ), while the closely related two-component regulators phoPQ and pmrAB were repressed by CaCl 2 addition. To identify the regulatory targets of CarSR, we constructed a deletion mutant of carR and performed transcriptome analysis of the mutant strain at low and high [Ca 2+ ]. Among the genes regulated by CarSR in response to CaCl 2 are the predicted periplasmic OB-fold protein, PA0320 (here called carO ), and the inner membrane-anchored five-bladed β-propeller protein, PA0327 (here called carP ). Mutations in both carO and carP affected Ca 2+ homeostasis, reducing the ability of P. aeruginosa to export excess Ca 2+ . In addition, a mutation in carP had a pleotropic effect in a Ca 2+ -dependent manner, altering swarming motility, pyocyanin production, and tobramycin sensitivity. Overall, the results indicate that the two-component system CarSR is responsible for sensing high levels of external Ca 2+ and responding through its regulatory targets that modulate Ca 2+ homeostasis, surface-associated motility, and the production of the virulence factor pyocyanin. IMPORTANCE During infectious disease, Pseudomonas aeruginosa encounters environments with high calcium (Ca 2+ ) concentrations, yet the cells maintain intracellular Ca 2+ at levels that are orders of magnitude less than that of the external environment. In addition, Ca 2+ signals P. aeruginosa to induce the production of several virulence factors. Compared to eukaryotes, little is known about how bacteria maintain Ca 2+ homeostasis or how Ca 2+ acts as a signal. In this study, we identified a two-component regulatory system in P. aeruginosa PAO1, termed CarRS, that is induced at elevated Ca 2+ levels. CarRS modulates Ca 2+ signaling and Ca 2+ homeostasis through its regulatory targets, CarO and CarP. The results demonstrate that P. aeruginosa uses a two-component regulatory system to sense external Ca 2+ and relays that information for Ca 2+ -dependent cellular processes.

Objectives To determine the cutoff value of early-morning urinary arginine vasopressin (uAVP)/urinary creatinine (uCr) for patients with nocturnal polyuria (NP), and to investigate whether abnormal secretion of AVP at nighttime is a risk factor of NP in elderly men. Methods A total of 189 men older than 50 years of age with nocturia were enrolled. The frequency volume chart was recorded. The uAVP, urinary sodium, uCr, and osmolarity of a single urine sample voided at 6:00 am were measured in all cases. Two definitions of NP—nocturnal urine volume/24-hr production greater than 0.35 (NP index [NPI] definition) and a nocturnal urine volume of 0.9 mL/min × the sleeping duration or greater (NUV definition)—were used for analysis. Results uAVP/uCr was an independent predictor for NP according to the NPI and NUV definitions. The cutoff value of uAVP/uCr for NP was 23.4 pg/mL/Cr according to the NPI definition and 28.3 pg/mL/Cr according to the NUV definition. The sensitivity of the cutoff value according to the NPI and NUV definitions was 69% and 77%, respectively, and the specificity was 61% and 66%, respectively. In both NP definitions, 31% and 38% of the patients with a uAVP/uCr greater than the cutoff value showed NP. Significant differences in NUV and urine osmolarity, but not in uAVP/uCr and uNa/uCr, between the NP group and the non-NP group were found using both NP definitions. Conclusions We demonstrated that age and uAVP/uCr were independent predictive factors for nocturia in patients with NP. The cutoff value of uAVP/uCr is a useful screening marker for NP in elderly men with nocturia.

Objectives To elucidate whether heart function and endocrine levels of arginine vasopressin (AVP) or solute diuresis is associated with the nocturnal voided volume, and whether the urinary AVP could be a parameter for screening for nocturnal polyuria caused by AVP insufficiency. Methods A total of 50 patients were enrolled in this study. The blood and urine samples were obtained every 6 hours at 6 pm , 12 am , 6 am , and 12 pm . Atrial natriuretic peptide and brain natriuretic peptide were measured at admission. All voided urine samples were collected every 6 hours for examination. The evaluation items were AVP, osmolarity, sodium, potassium, chloride, and creatinine in blood and urine. Results The patients were classified into a group with nocturnal polyuria (n = 21) and a group without nocturnal polyuria (n = 25). There was no significant difference in atrial natriuretic peptide, brain natriuretic peptide, electrolytes in blood and urine, and plasma AVP of each sample between the two groups, but urinary AVP/urinary creatinine and urine osmolarity at 12 am and 6 am in the group with nocturnal polyuria were significantly lower than those in the group without nocturnal polyuria. The nocturnal voided volume correlated with urinary AVP/urinary creatinine level in the urine samples obtained at 12 am and 6 am . Conclusions The present data have demonstrated that the significant decrease in urinary AVP/urinary creatinine level at 6 am may contribute to the increased nocturnal voided volume followed by nocturia and that the circadian rhythm disorder of AVP can be predicted by a noninvasive test measuring urinary AVP/urinary creatinine in the urine voided early in the morning.

Background : A pressure-flow study, although a slightly invasive procedure, can evaluate bladder outlet obstruction and detrusor contractility. This study was conducted in men with a non-enlarged prostate to determine the cause of urinary disturbance by less invasive examinations that might even- tually replace pressure-flow study. Methods : Thirty-six men with lower urinary tract symptoms were enrolled. Their prostate volume, estimated by transrectal ultrasonography, was less than 20 mL. All patients were examined using pressure-flow study, free-flowmetry, transrectal ultrasonography, prostate specific antigen and an interview using the International Prostate Symptom Score and Quality of Life Index. With determi- nation of the cause for urinary disturbance, parameters that correlated with outflow obstruction or impaired detrusor contractility were sought. Results : Twenty-one (60%) of the 36 men were judged as having outflow obstruction, and 16 of these 21 men had normal detrusor function. Impaired detrusor contractility was observed in 17 men. Only three of these 17 men had no outflow obstruction. Four patients had an unstable bladder. All these four had normal detrusor contractility, but had outflow obstruction. Among the parameters examined, only the maximum flow rate in a flow metrogram (Q max ) correlated significantly with the degree of outflow obstruction ( P = 0.04). The positive predictive value of Q max for outflow obstruction was 65% at a flow rate of less than 10 mL/s, and 100% at that of less than 5 mL/s. No parameter correlated with detrusor contractility. Conclusion : The only parameter that was a clear indicator of outflow obstruction was Q max . Other indicators of detrusor contractility should be sought.

With the increase in detection of incidental renal cell carcinoma, nephron-sparing surgery for small renal cell carcinomas is now recognized as one of the surgical options. We report a case of renal arteriovenous fistula developing after non-ischemic tumor enucleation of a small renal cell carcinoma using a microwave tissue coagulator. A 50-year-old Japanese man presented with right flank pain and gross hematuria. The patient had undergone non-ischemic tumor enucleation for right renal cell carcinoma, 2 cm in diameter, 1 month previously. Doppler ultrasound revealed the formation of an arteriovenous fistula at the enucleated portion. Transcatheter super-selective occlusion of the feeding artery was successfully performed with two metallic coils. The patient has been followed up with no sign of recanalization of the fistula. In this case, the tumor was located close to the renal hilus with thick arterial branches around the tumor. Additional microwave coagulations against arterial bleeding from the cutting surface might have been the cause of the fistula formation of this case. Non-ischemic tumor enucleation using a microwave tissue coagulator is a relatively easy and secure nephron-sparing surgical procedure. Excessive coagulation, however, should be avoided, since it might be the cause of unexpected postoperative vascular complications.

維持血液透析患者66例について, 新たな動脈硬化性物質として注目されているhomocysteineおよびメチオニン代謝系基質である葉酸の血中濃度を測定した. 血漿homocysteine濃度は12.6-182.0μmol/l (平均45.6±31.9μmol/l) と全例で高値を示すと同時に著しい個体差を認めた. 一方, 血清葉酸濃度は2.7-26.8ng/ml (平均7.5±4.1ng/ml) とほとんどの症例で基準値の範囲内にあった. また, 血清葉酸濃度と血漿homocysteine濃度には負の相関 (r=-0.245; P=0.0445) が認められた. さらに, 血清葉酸濃度15ng/ml以上では40μmol/l以上の高度のhomocysteine高値例は認められなかった. しかし, 通常の食生活で血清葉酸濃度が15ng/ml以上に維持できている症例は3例 (4.5%) に過ぎず, 残りの63例 (95.5%) は血清葉酸濃度15ng/ml以下であった. 今回の結果からacquired hyperhomocysteinemiaの状態にある維持血液透析患者においては通常の食生活のみでは血漿homocysteine濃度を正常に保つに十分な葉酸濃度を得ることはできず, 動脈硬化予防のためには積極的な葉酸投与の必要性が示唆された.

Background New diagnostic criteria for dynamic magnetic resonance (MR) imaging in prostate cancer are presented. The diagnostic usefulness of endorectal MR imaging with dynamic contrast-enhancement in localized prostate cancer and the validity of these criteria were evaluated. Methods Eighteen untreated patients who were suspected of localized prostate cancer were included in the study. They received endorectal dynamic MR imaging before systematic sextant needle biopsy. First. a mapping study with the findings of MR images and histopathology of biopsy specimens was performed in eight patients out of 18 to compare the difference in T2-weighted images with the endorectal coil and the body coil in the same individuals. Second, another mapping study was performed in all 18 patients by analyzing the findings of endorectal dynamic MR images. For the diagnosis of prostate cancer in MR imaging, we offered diagnostic criteria from our experience in addition to those in plain T2-weighted images from the literature. Results The overall diagnostic rates of endorectal dynamic MR imaging were 88.9% in accuracy, 100% in sensitivity, and 81.8% in specificity. In the comparison of the endorectal and body coils in T2-weighted images in eight patients, there was no difference in the diagnostic rates except for one more histopathologic false positive portion in endorectal MR imaging. In the second mapping study in 18 patients, the diagnostic rates were 92.6% in accuracy, 88.9% in sensitivity and 93.3% in specificity. Endorectal dynamic imaging raised the diagnostic sensitivity from 77.8 to 88.9%. Conclusion The data demonstrated the validity of this diagnostic criteria and the diagnostic usefulness of endorectal dynamic MR imaging in localized prostate cancer.

Background Serum levels of pyridinoline, measured by high-performance liquid chromatography, and pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen (ICTP), measured by a newly developed radioimmunoassay kit, were compared and analyzed to determine whether ICTP can replace pyridinoline as a marker of bone resorption in hemodialysis patients.

To determine the association of tetracycline resistance determinants with tigecycline sensitivity, tetracycline-resistant Salmonella spp. isolated from clinical and food samples were tested for the presence of tetracycline resistance determinants, tigecycline sensitivity, and the impact of tetA on tigecycline resistance. In addition, the impacts of multiple resistance mechanisms on tigecycline resistance were determined using an isolate with ramR mutation. Of the 49 tetracycline-resistant Salmonella isolates screened, 32 were positive for tetA , 13 were positive for tetB , 2 were positive for tetC and 1 isolate was positive for both tetA and tetB . The minimum inhibitory concentration (MIC) of tigecycline for tetA -carrying isolates ranged from 0.19mg/L to 3mg/L (mode 0.75mg/L), whereas the MIC of tigecycline for tetB -carrying isolates ranged from 0.064mg/L to 0.5mg/L (modes 0.25mg/L and 0.38mg/L, excluding the isolate with both tetA and tetB ). Double frameshift mutations in codons 201, 202 and 203 were observed in partial sequences of the tetA genes in these strains and the majority of published tetA gene sequences. Curing of the tetA genes from three isolates reduced the tigecycline MICs, whilst deletion of ramR increased tigecycline MICs. This study indicates that the tetA gene decreases sensitivity to tigecycline in Salmonella spp. at a low level. With additional resistance mechanisms, tetA -carrying strains can reach the breakpoint for tigecycline resistance.

To determine the fluoroquinolone resistance determinants in Salmonella enterica serovar Schwarzengrund from imported foods.Antibiotic susceptibility of Salmonella Schwarzengrund to 16 antibiotics was examined using disc agar diffusion and Etest. Quinolone resistance determinants were examined by sequence analysis of gyrA, gyrB, parC and parE, PCR amplification of qnrA, qnrB and qnrS, and expression of acrB, ramA, marA, soxS and rob using quantitative RT-PCR. The contribution of efflux pump activities to antibiotic resistance was determined by the addition of carbonyl cyanide m-chlorophenylhydrazone (CCCP). The effect of ramR deletion on ciprofloxacin resistance was determined by complementing with wild-type ramR.Salmonella strains 30 and 487 were susceptible to ciprofloxacin and had a single mutation in gyrA as compared with strain 75, which was highly resistant to ciprofloxacin and had a double mutation in gyrA. Increased expression of ramA was associated with high resistance to ciprofloxacin. Strain 75 had a deletion of 315 bp in the ramR gene, which regulates ramA expression. Overexpression of ramA was possibly related to a loss of ramR. Introduction of ramR decreased the MIC of ciprofloxacin from 48 to 24 mg/L. The addition of CCCP did not reduce antibiotic resistance. To our knowledge, this study reports for the first time the natural deletion of ramR in Salmonella Schwarzengrund.This study indicates that fluoroquinolone-resistant Salmonella are prevalent in imported food. Double mutations in gyrA and a loss of ramR were associated with high-level quinolone resistance in multidrug-resistant Salmonella Schwarzengrund strain 75.

The occurrence of broad-host-range (BHR) plasmid amplicons belonging to incompatibility (Inc) groups IncA/C, IncN, IncP, and IncW in two wastewater treatment plant (WWTP) effluents and effluent-receiving streams in Northwest Arkansas, Mud Creek and Spring Creek, was determined. Community DNA captured on filter membranes and plasmid DNA extracted from antibiotic-resistant Escherichia coli isolated from Mud Creek was used for polymerase chain reaction at amplification of partial gene sequences specific to BHR plasmids. IncP plasmid amplicons were detected in effluent and downstream sites in both streams, while IncN and IncW plasmid amplicons were detected in Spring Creek in effluent and downstream but not upstream. IncA/C plasmid amplicons, in contrast, were detected at all sites, including upstream in most samples in Spring Creek and in one sample from Mud Creek. One IncP and two IncN were the only BHR plasmid amplicons found in 85 screened antibiotic-resistant E. coli isolates, and were detected only in isolates from effluent and downstream samples. Broad-host-range plasmids frequently carry antibiotic-resistance genes and can facilitate horizontal transfer of those genes. While BHR plasmids have been detected in WWTPs, WWTPs do not target these genetic elements for destruction. This study indicates that BHR plasmids are in WWTP effluent and are introducing BHR plasmids into streams. Additionally, species other than E. coli may be better targets as indicator bacteria for future studies of the impact of treated effluent on environmental dissemination of BHR plasmids.

A total of 39 Salmonella enterica serovar Saintpaul strains from imported seafood, pepper and from environmental and clinical samples were analyzed for the presence of virulence genes, antibiotic resistance, plasmid and plasmid replicon types. Pulsed-field gel electrophoresis (PFGE) fingerprinting using the XbaI restriction enzyme and plasmid profiling were performed to assess genetic diversity. None of the isolates showed resistance to ampicillin, chloramphenicol, gentamicin, kanamycin, streptomycin, sulfisoxazole, and tetracycline. Seventeen virulence genes were screened for by PCR. All strains were positive for 14 genes (spiA, sifA, invA, spaN, sopE, sipB, iroN, msgA, pagC, orgA, prgH, lpfC, sitC, and tolC) and negative for three genes (spvB, pefA, and cdtB). Twelve strains, including six from clinical samples and six from seafood, carried one or more plasmids. Large plasmids, sized greater than 50 kb were detected in one clinical and three food isolates. One plasmid was able to be typed as IncI1 by PCR-based replicon typing. There were 25 distinct PFGE-XbaI patterns, clustered to two groups. Cluster A, with 68.5% similarity mainly consists of clinical isolates, while Cluster C, with 67.6% similarity, mainly consisted of shrimp isolates from India. Our findings indicated the genetic diversity of S. Saintpaul in clinical samples, imported seafood, and the environment and that this serotype possesses several virulent genes and plasmids which can cause salmonellosis.

Incomplete elimination of bacteria and pharmaceutical drugs during wastewater treatment results in the entry of antibiotics and antibiotic-resistant bacteria into receiving streams with effluent inputs. In Mud Creek in Fayetteville, AR, ofloxacin, trimethoprim, and sulfamethoxazole have been detected in water and sediment, and tetracycline has been detected in sediment downstream of treated effluent input. These antibiotics have been measured repeatedly, but at low concentrations (

Background: We report on an extremely rare case of urachal tuberculosis that was confirmed using a polymerase chain reaction test of paraffin-embedded material. Methods/Results: A 62-year-old man presented with pollakiuria. With a diagnosis of urachal abscess, the patient underwent en bloc resection of the cystic mass. A bacterial culture test of the content showed no organism. The histopathologic findings suggested urachal tuberculosis. The AMPLICOR polymerase chain reaction test by using paraffin-embedded sections revealed the existence of Mycobacterium tuberculosis in the resected tissue. The only positive finding in systemic screening examinations for tuberculosis was old tuberculosis scars in the upper right lung. It was supposed that hematogeneous spreading from the lung lesion may result in urachal tuberculosis after a long latent period. Conclusions: Although urachal tuberculosis is an extremely rare condition, tuberculosis must always be kept in mind when observing any infectious diseases.