High-Performance Genetically Encoded Green Fluorescent Biosensors for Intracellular l-Lactate

l-Lactate is a monocarboxylate produced during the process of cellular glycolysis and has long generally been considered a waste product. However, studies in recent decades have provided new perspectives on the physiological roles of l-lactate as a major energy substrate and a signaling molecule. To enable further investigations of the physiological roles of l-lactate, we have developed a series of high-performance (ΔF/F = 15 to 30 in vitro), intensiometric, genetically encoded green fluorescent protein (GFP)-based intracellular l-lactate biosensors with a range of affinities. We evaluated these biosensors in cultured cells and demonstrated their application in an ex vivo preparation of Drosophila brain tissue. Using these biosensors, we were able to detect glycolytic oscillations, which we analyzed and mathematically modeled.

Lactate biosensors for spectrally and spatially multiplexed fluorescence imaging

L-Lactate is increasingly appreciated as a key metabolite and signaling molecule in mammals. However, investigations of the inter- and intra-cellular dynamics of L-lactate are currently hampered by the limited selection and performance of L-lactate-specific genetically encoded biosensors. Here we now report a spectrally and functionally orthogonal pair of high-performance genetically encoded biosensors: a green fluorescent extracellular L-lactate biosensor, designated eLACCO2.1, and a red fluorescent intracellular L-lactate biosensor, designated R-iLACCO1. eLACCO2.1 exhibits excellent membrane localization and robust fluorescence response. To the best of our knowledge, R-iLACCO1 and its affinity variants exhibit larger fluorescence responses than any previously reported intracellular L-lactate biosensor. We demonstrate spectrally and spatially multiplexed imaging of L-lactate dynamics by coexpression of eLACCO2.1 and R-iLACCO1 in cultured cells, and in vivo imaging of extracellular and intracellular L-lactate dynamics in mice.

Evaluation of the Analytical Performance of the Fully Automated Gene Analyzer µTASWako g1 for the Detection of SARS-CoV-2

BACKGROUND

The worldwide spread of coronavirus disease 2019 (COVID-19) has led to an urgent need for nucleic acid amplification test (NAAT) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Because NAAT has many manual processes, results may vary depending on the operator. Therefore, it has been required to develop a fully automated testing device and reagent that detects genetic material from SARS-CoV-2. The µTASWako g1 system (FUJIFILM Wako Pure Chemical Corporation, Osaka, Japan), a genetic analyzer, provides results in 75 minutes by performing a fully automated PCR process.

METHODS

We evaluated the analytical and clinical performance of the µTASWako g1 system for the detection of SARS-CoV-2 RNA.

RESULTS

The µTASWako g1 system had the limit of detection at 2,000 copies/mL using a known concentration of RNA. In clinical samples, the µTASWako g1 system had a sensitivity of 88.0% and 100% specificity compared to conventional RT-PCR. The µTAS Wako g1 system could detect three variants of concern carrying spike mutations including N501Y, E484K, and L452R.

CONCLUSIONS

As the assay on the µTASWako g1 system is highly accurate for the detection of SARS-CoV-2 regardless of the experience of operator, it can be widely applicable in clinical laboratories.

A Polyimide Film-Based Simple Force Plate for Measuring the Body Mass of Tiny Insects

Insects exhibit excellent maneuvers such as running and flying despite their small bodies; therefore, their locomotion mechanism is expected to provide a design guideline for micromachines. Numerical simulations have been performed to elucidate this mechanism, whereby it is important to develop a model that is physically identical to the target insect's parts to reproduce kinematic dynamics. In particular, in flight, the shape and mass of wings, which flap at high frequencies, are significant parameters. However, small insects such as fruit flies have small, thin, and light wings; thus, their mass cannot be easily measured. In this study, we proposed a high-resolution and simple force plate to measure the mass of each part of a tiny insect. The device consists of a circular plate supported by flat spiral springs made of polyimide film, and a laser displacement meter that detects the displacement of the center of the plate. The simple plate fabrication process requires only a couple of minutes. A fabricated force plate with a sub-N/m spring constant achieved a resolution of less than 2 µg. As a demonstration, the wing mass of the fruit flies was measured. The experimental results suggest that the wings accounted for approximately 0.4% of the body mass.

Risk and Resilience in Trajectories of Post-Traumatic Stress Symptoms among First Responders after the 2011 Great East Japan Earthquake: a 7-year prospective cohort study

Introduction

First responders to disasters are at risk of developing post-traumatic stress disorder (PTSD). The trajectories of post-traumatic stress symptom severity differ among individuals, even if they are exposed to similar events. These trajectories have not yet been reported in non-Western first responders.

Objectives

We aimed to explore post-traumatic stress symptom severity trajectories and their risk factors in first responders to the 2011 Great East Japan Earthquake (GEJE)— a historically large earthquake that resulted in a tsunami and a nuclear disaster.

Methods

56 388 Japan Ground Self-Defense Force (JGSDF) personnel dispatched to the GEJE were enrolled in this seven-year longitudinal cohort study. PTSD symptom severity was measured using the Impact of Event Scale-Revised (IES-R). Trajectories were identified using latent growth mixture models (LGMM). Nine potential risk factors for the symptom severity trajectories were analyzed using multinomial logistic regression.

Results

Five symptom severity trajectories were identified: “resilient” (54.7%), “recovery” (24.5%), “incomplete recovery” (10.7%), “late-onset” (5.7%), and “chronic” (4.3%). The main risk factors for the four non-resilient trajectories were older age, personal disaster experiences, and working conditions. These working conditions included duties involving body recovery or radiation exposure risk, longer deployment length, later or no post-deployment leave, and longer post-deployment overtime.

Conclusions

The majority of first responders to GEJE were resilient and developed few or no PTSD symptoms. A substantial minority experienced late-onset and chronic symptom severity trajectories. The identified risk factors can inform policies for prevention, early detection, and intervention in individuals at risk of developing symptomatic trajectories.

Disclosure

No significant relationships.

High-power laser experiment forming a supercritical collisionless shock in a magnetized uniform plasma at rest

We present an experimental method to generate quasiperpendicular supercritical magnetized collisionless shocks. In our experiment, ambient nitrogen (N) plasma is at rest and well magnetized, and it has uniform mass density. The plasma is pushed by laser-driven ablation aluminum (Al) plasma. Streaked optical pyrometry and spatially resolved laser collective Thomson scattering clarify structures of plasma density and temperatures, which are compared with one-dimensional particle-in-cell simulations. It is indicated that just after the laser irradiation, the Al plasma is magnetized by a self-generated Biermann battery field, and the plasma slaps the incident N plasma. The compressed external field in the N plasma reflects N ions, leading to counterstreaming magnetized N flows. Namely, we identify the edge of the reflected N ions. Such interacting plasmas form a magnetized collisionless shock.

Association between adherence to home-based walking exercise with a pedometer and one-year adverse outcomes among lower extremity peripheral artery disease patients with endovascular treatment

Background

Home-based exercise after endovascular treatment (EVT) for lower extremity peripheral artery disease (LE-PAD) patients with intermittent claudication is suggested as an alternative therapy for supervised exercise; however, an association of adherence to home-based exercise with clinical adverse events has not been fully investigated.

Purpose

We aimed to investigate the association of adherence to home-based exercise with 1-year major adverse events (MAE), patency, and leg symptoms after EVT in a contemporary Japanese registry.

Methods

A total of 500 patients with LE-PAD within the Long Term Outcome of Endovascular Therapy for PAD with Intermittent Claudication Observational Prospective Multicenter (ASHIMORI-IC) registry (UMINCTR, UMINehab724.203718753) who underwent EVT between January 2016 and March 2019 were included in the analysis. After EVT, all patients were instructed to do home-based walking exercise with a pedometer. The study population was divided and compared between 2 groups according to adherence to home-based exercise: well-adherence and poor-adherence. The adherence of home-based exercise was as defined by step count derived from a pedometer on sites. The primary outcome was MAE defined as composite of all-cause death, myocardial infarction, stroke, target vessel revascularization, and major amputation of target lower limb for one year. The main secondary outcome was 1-year primary patency of the treated lesion, and the improvement of leg symptom (6-minute walk distance [6MWD] and claudication distance). The study followed the Consensus definitions from peripheral academic research consortium criteria.

Results

Overall, the mean age was 72.8 years, and 78% were men. At 1 year, MAE occurred in 45 patients (9.0%), and the primary patency rate was 85.3% (94.2% of EVT for aortoiliac and 71.9% of EVT for femoropopliteal). A significant difference in the incidence of MAE was observed between the well-adherence group and the poor-adherence group (10 of 233 patients [4.3%] vs. 35 of 267 patients [13.1%]; P<0.001). After multivariate Cox regression analysis, patients in the well-adherence group showed the lower hazard ratio for 1-year MAE (0.30; 95% confidence interval, 0.15–0.58; P<0.001) compared to those in the poor-adherence group. In the well-adherence group, compared with the poor-adherence group, higher primary patency rate (88.9% vs 81.5%; p=0.015), longer claudication onset distance (370 m [IQR 240–453 m] vs 240m [IQR 126–324 m]; P<0.001), and longer 6MWD (422 m [IQR 359–483 m] vs 325 m [IQR 213–400 m]; P<0.001) were observed even after adjusting for each baseline value.

Conclusion

Our study demonstrates the importance of adherence to home-based walking exercise after EVT in LE-PAD patients.

Funding Acknowledgement

Type of funding sources: None.

Short and long sleeping mutants reveal links between sleep and macroautophagy

Sleep is a conserved and essential behavior, but its mechanistic and functional underpinnings remain poorly defined. Through unbiased genetic screening in Drosophila, we discovered a novel short-sleep mutant we named argus. Positional cloning and subsequent complementation, CRISPR/Cas9 knock-out, and RNAi studies identified Argus as a transmembrane protein that acts in adult peptidergic neurons to regulate sleep. argus mutants accumulate undigested Atg8a(+) autophagosomes, and genetic manipulations impeding autophagosome formation suppress argus sleep phenotypes, indicating that autophagosome accumulation drives argus short-sleep. Conversely, a blue cheese neurodegenerative mutant that impairs autophagosome formation was identified independently as a gain-of-sleep mutant, and targeted RNAi screens identified additional genes involved in autophagosome formation whose knockdown increases sleep. Finally, autophagosomes normally accumulate during the daytime and nighttime sleep deprivation extends this accumulation into the following morning, while daytime gaboxadol feeding promotes sleep and reduces autophagosome accumulation at nightfall. In sum, our results paradoxically demonstrate that wakefulness increases and sleep decreases autophagosome levels under unperturbed conditions, yet strong and sustained upregulation of autophagosomes decreases sleep, whereas strong and sustained downregulation of autophagosomes increases sleep. The complex relationship between sleep and autophagy suggested by our findings may have implications for pathological states including chronic sleep disorders and neurodegeneration, as well as for integration of sleep need with other homeostats, such as under conditions of starvation.

Evolutionary Origin of Distinct NREM and REM Sleep

Sleep is mandatory in most animals that have the nervous system and is universally observed in model organisms ranging from the nematodes, zebrafish, to mammals. However, it is unclear whether different sleep states fulfill common functions and are driven by shared mechanisms in these different animal species. Mammals and birds exhibit two obviously distinct states of sleep, i.e., non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep, but it is unknown why sleep should be so segregated. Studying sleep in other animal models might give us clues that help solve this puzzle. Recent studies suggest that REM sleep, or ancestral forms of REM sleep might be found in non-mammalian or -avian species such as reptiles. These observations suggest that REM sleep and NREM sleep evolved earlier than previously thought. In this review, we discuss the evolutionary origin of the distinct REM/NREM sleep states to gain insight into the mechanistic and functional reason for these two different types of sleep.

Triglyceride to HDL-cholesterol ratio is a predictor of future coronary events: a possible role of high-risk coronary plaques detected by coronary CT angiography

Background

For the prevention of future cardiovascular events, control of residual risks such as triglyceride rich lipoproteins and HDL-cholesterol is an emerging problem beyond LDL-cholesterol. Triglyceride to HDL-cholesterol ratio (TG/HDL ratio) has been reported to be useful for risk classification of cardiovascular diseases. Meanwhile, several studies showed that high-risk plaque characteristics evaluated with coronary CT angiography (cCTA) was associated with the incidence of acute coronary syndrome. However, the relationship of TG/HDL ratio with coronary plaque characteristics and its impact of this association on future coronary events have not been fully elucidated.

Purpose

The aim of this study was to evaluate the association between TG/HDL ratio and high-risk plaque detected by cCTA and its impact on future coronary events.

Methods

A total of 944 patients suspected stable coronary artery disease who underwent cCTA at our institution were analyzed (mean 64-year-old, 55% male). Patients were divided into two groups by the median value of TG/HDL ratio (higher TG/HDL: TG/HDL ratio ≥2.0, lower TG/HDL: TG/HDL ratio <2.0). Coronary high-risk plaques were defined as a plaque with all three components; low attenuation plaque (<50H.U.), positive remodeling (remodeling index >1.1) and spotty calcification. Cardiovascular event was defined as cardiovascular death, acute coronary syndrome, and late coronary revascularization after 30 days of CT acquisition.

Results

The higher TG/HDL ratio was significantly associated with male gender (63% vs. 48%, P<0.001), body mass index (24.8±3.8 vs. 22.9±4.0, p<0.001), the prevalence of hypertension (65% vs. 54%, P<0.001), dyslipidemia (60% vs. 42%, P<0.001), diabetes mellitus (38% vs. 27%, P=0.001) and current smoking (26% vs. 10%, p<0.001). Regarding cCTA findings, the prevalence of significant stenosis, calcified plaque, non-calcified plaque, coronary plaques with low attenuation plaque, positive remodeling and spotty calcification in the higher TG/HDL group were greater than those in the lower group (Figure 1A). Of note, the difference in high-risk plaque between two groups was significant. (18% vs. 11%, p=0.004). Multivariate logistic analysis revealed that the TG/HDL ratio was an independent risk factor for high-risk plaque even after adjustment (OR, 1.35; 95% CI, 1.01–1.81; p=0.049). Regarding coronary events (median follow-up duration; 48 months), Kaplan-Meier curve showed poor event-free rate in the higher TG/HDL group (Figure 1B). At Cox proportional hazard analysis, higher TG/HDL ratio (HR, 1.94; 95% CI, 1.01–3.70; p=0.046) and CT-verified high-risk plaque (HR, 2.36; 95% CI, 1.27–4.38; p=0.006) were independent predictive factors for coronary events even after adjustment.

Conclusion

TG/HDL ratio is involved in the vulnerability of CT-verified coronary plaque characteristics. This association may play an important role in the prognostic impact of TG/HDL ratio on future cardiovascular events.

Funding Acknowledgement

Type of funding source: None

Epidemiological and molecular characterization of invasive Streptococcus pneumoniae isolated following introduction of 7-valent conjugate vaccine in Kinki region, Japan, 2008-2013

Streptococcus pneumoniae is one of the most common bacteria causing community-acquired pneumonia and meningitis. The use of 7-valent pneumococcal conjugate vaccine (PCV7) has reduced the incidence of pneumococcal disease while changing pneumococcal population through herd immunity and non-vaccine pneumococci replacement. This study investigated molecular epidemiologic characteristics of pneumococcal strains in the Kinki region of Japan from 2008 to 2013. A total of 159 invasive pneumococcal isolates were characterized by serotyping, antibiotic susceptibility testing, PCR analysis of penicillin-binding protein genes, multilocus sequence typing (MLST), and pulsed-field gel electrophoresis (PFGE). In adult populations, pediatric PCV7 introduction decreased isolates expressing PCV7 serotypes via herd immunity and increased isolates expressing non-PCV7 serotypes. The rate of penicillin resistance and isolates with alterations in all three pbp genes was higher in PCV7 type isolates than in non-PCV7 type isolates. In MLST analysis, all of serotype 19F isolates were of the same sequence type, ST236, which is the antimicrobial-resistant clone Taiwan^19F-14, and the majority of serotypes 23F and 19A isolates were of ST1437 and ST3111 respectively, which are the predominant clones of antimicrobial-resistant pneumococci in Japan. In PFGE profiles, serotype 6B-ST2224, serotype 19F-ST236, serotype 19A-ST3111, and serotype 23F-ST1437 formed six separate clusters composed of genetically identical strains, and genetically identical serotype 22F-ST433 formed two different clusters between the pre- and post-PCV7 period. The results of molecular analysis suggest the spread and persistence of these identical antimicrobial resistant clones in the Kinki region and genetic changes of epidemic clone serotype 22F-ST433 before and after pediatric PCV7 introduction.

1407Drug effect of luseogliflozin and voglibose on heart failure with preserved ejection fraction in diabetic patients: a multicenter randomized-controlled trial

Background

Recent randomized, placebo-controlled trial in patients with type 2 diabetes demonstrated that the sodium-glucose cotransporter 2 inhibitors reduced mortality, cardiovascular events and hospitalization for heart failure. However, those trials were not specialized design to investigate the effect of sodium-glucose cotransporter 2 inhibitors in patients with heart failure, in particular with heart failure with preserved ejection fraction.

Purpose

The aim of this study was to evaluate the drug efficacy of luseogliflozin, a sodium-glucose cotransporter 2 inhibitor, compared with voglibose, an alpha-glucosidase inhibitor, using brain natriuretic peptide (BNP) in type 2 diabetes patients with heart failure with preserved ejection fraction.

Methods

This study was a prospective, multicenter, open-label, randomized-controlled trial, comparing luseogliflozin 2.5 mg once daily or voglibose 0.2 mg three times daily in patients with type 2 diabetes suffering from heart failure with preserved ejection fraction (left ventricular ejection fraction >45% and BNP ≥35 pg/ml2) in a 1:1 randomization fashion. Randomization was undertaken using a computer-generated random sequence web response system. The primary outcome was the difference from baseline in BNP after 12 weeks of treatment between two drugs. The key secondary outcomes were the change from baseline in left ventricular ejection fraction and E/e' in echocardiographic parameters, body weight, glycohemoglobin level after 12 weeks of treatment. The safety outcomes included the incidence of major adverse cardiovascular events, hypoglycemic adverse events, and urinary tract infection.

Results

Between December 2015 and September 2018, 173 patients from 16 hospitals and clinics have been included in this study. Of those, 83 patients were assigned to receive luseogliflozin and 82 to receive voglibose. There was no significant difference in the reduction in the BNP concentration after 12 weeks from baseline between the two groups; the ratio of the average values at week 12 to the baseline value was 0.91 in the luseoglifllzin group as compared with 0.98 in the voglibose group (percent change, −9.0% vs. −1.9%, ratio of change with luseogliflozin vs. voglibose, 0.93; 95% confidence interval, 0.78 to 1.10; p=0.26). The key secondary outcomes including left ventricular ejection fraction, E/e', body weight, glycohemoglobin level and the safety outcomes did not differ significantly between the two groups.

Conclusions

In type 2 diabetes patients with heart failure with preserved ejection fraction, the administration of luseogliflozin did not lead to a significant reduction in the BNP concentration than that of voglibose. Left ventricular ejection fraction, E/e', body weight and glycohemoglobin level after 12 weeks of treatment, comparing with at baseline did not differ significantly between the two groups. (UMIN Clinical Trial Registry number, UMINehz748.005618395)

Acknowledgement/Funding

Novartis

A sleep-inducing gene, nemuri, links sleep and immune function in Drosophila

Sleep remains a major mystery of biology. In particular, little is known about the mechanisms that account for the drive to sleep. In an unbiased screen of more than 12,000 Drosophila lines, we identified a single gene, nemuri, that induces sleep. The NEMURI protein is an antimicrobial peptide that can be secreted ectopically to drive prolonged sleep (with resistance to arousal) and to promote survival after infection. Loss of nemuri increased arousability during daily sleep and attenuated the acute increase in sleep induced by sleep deprivation or bacterial infection. Conditions that increase sleep drive induced expression of nemuri in a small number of fly brain neurons and targeted it to the sleep-promoting, dorsal fan-shaped body. We propose that NEMURI is a bona fide sleep homeostasis factor that is particularly important under conditions of high sleep need; because these conditions include sickness, our findings provide a link between sleep and immune function.

Genetic Mechanisms Underlying Sleep

Sleep is important for cognitive ability, and perturbations of sleep are associated with a myriad of brain disorders. However, how sleep promotes health and function during wake is poorly understood. To address the cellular and molecular mechanisms underlying sleep, we use the fruit fly Drosophila melanogaster as a genetic model. Forward genetic approaches in flies were critical for deciphering molecular mechanisms of the circadian clock. Using similar approaches, we and others are gaining insights into the pathways that control sleep amount.

Relationship Between Stress Coping Mechanisms and Depression in Kidney Transplant Recipients

BACKGROUND

It has been reported that transplant recipients are exposed to physical and psychosocial stresses even after transplant surgery and exhibit psychological disorders such as depression.

PURPOSE

In this study, we extracted trends concerning how recipients of kidney transplants cope with stress, and we also examined how they cope with depression and its countermeasures.

METHOD

We administered questionnaire surveys to 109 kidney transplant recipients. These included items on personal attributes, medical information, depression, and stress-coping type scales. Statistical analysis was performed using factor analysis and multiple regression analysis.

RESULTS

Fifteen out of 109 (13.8%) were found to be high-risk patients for depression based on responses to the questionnaire using the depression scale. We extracted 2 factors of stress-coping type, namely Factor 1, "Directly coping with the problem," of patients who try to directly resolve the problem in a positive manner and Factor 2, "Stress-release while avoiding the problem," for those who relieve their feelings in response to the stress without resolving the problem itself. When multiple regression analysis was conducted with the depression scale as the dependent variable and the stress-coping factor as the independent variable, Factor 1 tended to be associated with reduced depression and Factor 2 with increased depression.

CONCLUSIONS

Results showed that to improve the mental health of those who receive kidney transplants, it is necessary to examine the depression and stress-coping types of such patients at an early stage and carry out education on stress-coping, focusing on resolving the actual problem.

Laboratory surveillance of antimicrobial resistance and multidrug resistance among Streptococcus pneumoniae isolated in the Kinki region of Japan, 2001-2015

The 7-valent pneumococcal conjugate vaccine (PCV7) was introduced among children in Japan in 2010. There are no long-term multicenter surveillance studies of antimicrobial resistance in S. pneumoniae before and after the introduction of PCV7. Therefore, we examined chronological trends in antimicrobial resistance among 4534 strains of S. pneumoniae isolated from both children and adults in the Kinki region of Japan during 2001-2015. High-level penicillin and third-generation cephalosporin resistance in S. pneumoniae increased among both children and adults during the period before the introduction of PCV7 (2001-2010). Besides penicillin and cephalosporin, pneumococcal carbapenem and macrolide resistance increased among children. The rate of resistance to these antibiotics was higher among children than among adults. The introduction of PCV7 decreased the rate of non-susceptibility to β-lactam antibiotics and the rate of multidrug resistant S. pneumoniae among children, but not among adults.

Girdin maintains the stemness of glioblastoma stem cells

This corrects the article DOI: 10.1038/onc.2011.466.

[The annual changes in antimicrobial susceptibility test results of Pseudomonas aeruginosa isolates from the Kinki district]

A study was conducted of the 1,225 Pseudomonas aeruginosa strains that were isolated at 20 medical institutions in the Kinki district between 2011 and 2013 to determine their antimicrobial susceptibility and to characterize the strains of multidrug-resistant Pseudomonas aeruginosa (MDRP) and the metallo-β-lactamase (MBL) -producing strains. The MIC50/MIC90 values (μg/mL) of the various antimicrobial agents were as follows: imipenem, 2/>8; meropenem, 1/>8; doripenem, 0.5/8; biapenem, 1/>8; tazobactam/piperacillin, 8/>64; piperacillin, 8/>64; sulbactam/cefoperazone, 8/64; cefepime, 4/16; cefozopran, 2/>16; aztreonam, 8/>16; amikacin, 4/16; levofloxacin, 1/>4; and ciprofloxacin, 0.25/>2. From the viewpoint of the annual changes in the susceptibility rates (according to the CLSI guidelines [M100-S22]), the susceptibility to tazobactam/piperacillin, piperacillin, cefepime, cefozopran and aztreonam decreased in 2013. On the other hand, two antimicrobial agents showed high susceptibility rates each year; amikacin (94.0-95.6%) showed the highest rate, followed by doripenem (80.3-82.6%). With the exception of amikacin, there were substantial inter-institutional differences in antimicrobial susceptibility. In comparison to the previous CLSI guidelines (M100-S21), the new CLSI guidelines (M100-S22) on the use of carbapenems and penicillins show that the MIC80 has been affected. The MDRP detection rates in 2011, 2012 and 2013 were 1.8% (8 strains), 1.8% (8 strains), and 2.8% (10 strains), respectively. The MBL detection rates were as follows: bla(VIM-2), 0.2% (1 strain) in 2011; bla(IMP-1), 0.9% (4 strains) in 2012, and 1.7% (6 strains, including bla(IMP-1) [3 strains], bla(IMP-2) [2 strains] and bla(VIM-2) [1 strain]) in 2013.

Low serum potassium concentration is a predictor of chronic kidney disease

AIMS

The aim of this study was to examine whether low serum potassium concentration could be a predictor of chronic kidney disease (CKD) in a community-based cohort.

MATERIALS AND METHODS

We enrolled 1001 subjects, median period of 5.7 years, and evaluated the risk factors for CKD, defined as estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73 m(2), and assessed whether low serum potassium concentration could predict CKD.

RESULTS

Compared with the subjects without development of CKD, age, body mass index, fasting plasma glucose, uric acid (UA), creatinine and serum sodium concentration were higher, and serum potassium concentration was lower in subjects with development of CKD. Univariate Cox regression analyses demonstrated that age, body mass index, fasting plasma glucose, UA, creatinine, serum sodium concentration and serum potassium concentration were associated with progression of CKD. Multiple Cox regression analysis revealed that age, gender, creatinine and serum potassium concentration were independent predictors of CKD after adjustment for covariates. When serum potassium concentration was below 4.0 mmol/l at baseline, hazard ratio (95% confidence interval) of developing CKD was 2.65 (2.04-3.44; p < 0.0001).

CONCLUSIONS

Serum potassium concentration could be a clinically relevant risk factor for the progression of CKD, defined as eGFR < 60 ml/min/1.73 m(2) , in healthy subjects.

Andropausal symptoms in men with Type 2 diabetes

AIMS

Serum androgen concentration is reported to be low in patients with Type 2 diabetes. There have been no studies comparing andropausal symptoms such as sleep disturbance, depression, erectile dysfunction and lower urinary tract symptoms simultaneously between men with Type 2 diabetes and subjects without diabetes.

METHODS

We compared andropausal symptom scores such as the Pittsburgh Sleep Quality Index, the Self-Rating Depression Scale, the International Index of Erectile Function and the International Prostate Symptom Score in 296 men with Type 2 diabetes and in 267 subjects without diabetes. Furthermore, we evaluated relationships of andropausal symptom scores to various anthropometric factors and compared andropausal symptom scores according to diabetic complications in men with Type 2 diabetes.

RESULTS

Andropausal symptom scores such as the Pittsburgh Sleep Quality Index, the Self-Rating Depression Scale, the International Index of Erectile Function and the International Prostate Symptom Score were 4.2 ± 2.6 vs. 5.0 ± 3.3, P<0.01 by unpaired Student's t-test, 34.8 ± 8.2 vs. 38.4 ± 9.3, P<0.0001, 11.5 ± 6.4 vs. 9.9 ± 6.9, P<0.01 and 7.3 ± 6.7 vs. 9.0 ± 7.1, P<0.01 in subjects without diabetes and in patients with diabetes, respectively. The Pittsburgh Sleep Quality Index was higher in patients with neuropathy than without. The Self-Rating Depression Scale was higher in patients with advanced retinopathy. The International Index of Erectile Function was lower in patients with advanced retinopathy and nephropathy. The International Index of Erectile Function was lower and the International Prostate Symptom Score was higher in patients with cardiovascular disease than without.

CONCLUSIONS

Our data demonstrated that men with Type 2 diabetes have higher prevalence of andropausal symptoms, especially those with diabetic complications.

Epidemiology of Escherichia coli, Klebsiella species, and Proteus mirabilis strains producing extended-spectrum β-lactamases from clinical samples in the Kinki Region of Japan

In the present study, nonduplicate, clinical isolates of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli, Klebsiella spp, and Proteus mirabilis were collected during a 10-year period from 2000 to 2009 at several hospitals in the Kinki region, Japan. The detection rate of E coli markedly increased from 0.24% to 7.25%. The detection rate of Klebsiella pneumoniae increased from 0% to 2.44% and that of P mirabilis from 6.97% to 12.85%. The most frequently detected genotypes were the CTX-M9 group for E coli, the CTX-M2 group for K pneumoniae, and the CTX-M2 group for P mirabilis. E coli clone O25:H4-ST131 producing CTX-M-15, which is spreading worldwide, was first detected in 2007. The most common replicon type of E coli was the IncF type, particularly FIB, detected in 466 strains (69.7%). Of the K pneumoniae strains, 47 (55.3%) were of the IncN type; 77 P mirabilis strains (96.3%) were of the IncT type. In the future, the surveillance of various resistant bacteria, mainly ESBL-producing Enterobacteriaceae, should be expanded to prevent their spread.

Girdin maintains the stemness of glioblastoma stem cells

Glioblastomas (GBMs) are the most common and aggressive type of brain tumor. GBMs usually show hyperactivation of the PI3K-Akt pathway, a pro-tumorigenic signaling cascade that contributes to pathogenesis. Girdin, an actin-binding protein identified as a novel substrate of Akt, regulates the sprouting of axons and the migration of neural progenitor cells during early postnatal-stage neurogenesis in the hippocampus. Here, we show that Girdin is highly expressed in human glioblastoma (GBM). Stable Girdin knockdown in isolated GBM stem cells resulted in decreased expression of stem cell markers, including CD133, induced multilineage neural differentiation, and inhibited in vitro cell motility, ex vivo invasion, sphere-forming capacity and in vivo tumor formation. Furthermore, exogenous expression of the Akt-binding domain of Girdin, which competitively inhibits its Akt-mediated phosphorylation, diminished the expression of stem cell markers, SOX2 and nestin, and migration on the brain slice and induced the expression of neural differentiation markers glial fibrillary acidic protein/βIII Tubulin. Our results reveal that Girdin is required for GBM-initiating stem cells to sustain the stemness and invasive properties.

Unc-51/ATG1 controls axonal and dendritic development via kinesin-mediated vesicle transport in the Drosophila brain

BACKGROUND

Members of the evolutionary conserved Ser/Thr kinase Unc-51 family are key regulatory proteins that control neural development in both vertebrates and invertebrates. Previous studies have suggested diverse functions for the Unc-51 protein, including axonal elongation, growth cone guidance, and synaptic vesicle transport.

METHODOLOGY/PRINCIPAL FINDINGS

In this work, we have investigated the functional significance of Unc-51-mediated vesicle transport in the development of complex brain structures in Drosophila. We show that Unc-51 preferentially accumulates in newly elongating axons of the mushroom body, a center of olfactory learning in flies. Mutations in unc-51 cause disintegration of the core of the developing mushroom body, with mislocalization of Fasciclin II (Fas II), an IgG-family cell adhesion molecule important for axonal guidance and fasciculation. In unc-51 mutants, Fas II accumulates in the cell bodies, calyx, and the proximal peduncle. Furthermore, we show that mutations in unc-51 cause aberrant overshooting of dendrites in the mushroom body and the antennal lobe. Loss of unc-51 function leads to marked accumulation of Rab5 and Golgi components, whereas the localization of dendrite-specific proteins, such as Down syndrome cell adhesion molecule (DSCAM) and No distributive disjunction (Nod), remains unaltered. Genetic analyses of kinesin light chain (Klc) and unc-51 double heterozygotes suggest the importance of kinesin-mediated membrane transport for axonal and dendritic development. Moreover, our data demonstrate that loss of Klc activity causes similar axonal and dendritic defects in mushroom body neurons, recapitulating the salient feature of the developmental abnormalities caused by unc-51 mutations.

CONCLUSIONS/SIGNIFICANCE

Unc-51 plays pivotal roles in the axonal and dendritic development of the Drosophila brain. Unc-51-mediated membrane vesicle transport is important in targeted localization of guidance molecules and organelles that regulate elongation and compartmentalization of developing neurons.

UNC-51/ATG1 kinase regulates axonal transport by mediating motor-cargo assembly

Axonal transport mediated by microtubule-dependent motors is vital for neuronal function and viability. Selective sets of cargoes, including macromolecules and organelles, are transported long range along axons to specific destinations. Despite intensive studies focusing on the motor machinery, the regulatory mechanisms that control motor-cargo assembly are not well understood. Here we show that UNC-51/ATG1 kinase regulates the interaction between synaptic vesicles and motor complexes during transport in Drosophila. UNC-51 binds UNC-76, a kinesin heavy chain (KHC) adaptor protein. Loss of unc-51 or unc-76 leads to severe axonal transport defects in which synaptic vesicles are segregated from the motor complexes and accumulate along axons. Genetic studies show that unc-51 and unc-76 functionally interact in vivo to regulate axonal transport. UNC-51 phosphorylates UNC-76 on Ser(143), and the phosphorylated UNC-76 binds Synaptotagmin-1, a synaptic vesicle protein, suggesting that motor-cargo interactions are regulated in a phosphorylation-dependent manner. In addition, defective axonal transport in unc-76 mutants is rescued by a phospho-mimetic UNC-76, but not a phospho-defective UNC-76, demonstrating the essential role of UNC-76 Ser(143) phosphorylation in axonal transport. Thus, our data provide insight into axonal transport regulation that depends on the phosphorylation of adaptor proteins.

Stimulatory action of protein kinase C(epsilon) isoform on the slow component of delayed rectifier K+ current in guinea-pig atrial myocytes

BACKGROUND AND PURPOSE

Protein kinase C (PKC) comprises at least twelve isoforms and has an isoform-specific action on cardiac electrical activity. The slow component of delayed rectifier K(+) current (I (Ks)) is one of the major repolarizing currents in the hearts of many species and is also potentiated by PKC activation. Little is known, however, about PKC isoform(s) functionally involved in the potentiation of I (Ks) in native cardiac myocytes.

EXPERIMENTAL APPROACH

I (Ks) was recorded from guinea-pig atrial myocytes, using the whole-cell configuration of patch-clamp method.

KEY RESULTS

Bath application of phenylephrine enhanced I (Ks) concentration-dependently with EC(50) of 5.4 microM and the maximal response (97.1+/-11.9% increase, n=16) was obtained at 30 microM. Prazosin (1 microM) almost totally abolished the potentiation of I (Ks) by phenylephrine, supporting the involvement of alpha(1)-adrenoceptors. The stimulatory action of phenylephrine was significantly, if not entirely, inhibited by the general PKC inhibitor bisindolylmaleimide I but was little affected by Gö-6976, Gö-6983 and rottlerin. Furthermore, this stimulatory effect was significantly reduced by dialyzing atrial myocytes with PKCepsilon-selective inhibitory peptide epsilonV1-2 but was not significantly affected by conventional PKC isoform-selective inhibitory peptide betaC2-4. Phorbol 12-myristate 13-acetate (PMA) at 100 nM substantially increased I (Ks) by 64.2+/-1.3% (n=6), which was also significantly attenuated by an internal dialysis with epsilonV1-2 but not with betaC2-4.

CONCLUSIONS AND IMPLICATIONS

The present study provides experimental evidence to suggest that, in native guinea-pig cardiac myocytes, activation of PKC contributes to alpha(1)-adrenoceptor-mediated potentiation of I (Ks) and that epsilon is the isoform predominantly involved in this PKC action.

[A case of Mycobacterium goodii infection wifh isolation from blood and a pacemaker lead]

We report a case of blood stream infection due to Mycobacterium goodii in a patient who had an implanting pacemaker. The patient injured left thorax where the pacemaker was implanted several days before septicemia. The microorganism was isolated from both blood cultures and leads of the pacemaker. The serial isolates were identified as M. goodii by conventional biochemical methods, tobramycin susceptibility test and 16Sr-RNA sequencing. This is the first reported case of M. goodii septicemia in Japan. M. goodii is regarded as an environmental bacterium and its pathogenicity has been recognized recently. The present case suggests that its ability as a primary invader should not be underestimated, especially in a patient with indwelling devices.

High-speed gas sensor for chemosensory event-related potentials or magnetic fields

The observation of odor and air exchange with high temporal accuracy is necessary to obtain strict chemosensory event-related potentials (CSERPs) or magnetic fields, as proposed by Evans et al. [Evans W, Kobal G, Lorig T, Prah J. Suggestions for collection and reporting of chemosensory (olfactory) event-related potentials. Chem Senses, 1993; 18: 751- 6]. No suitable method for real time observation of gas stimuli, however, has been available until now. We have developed a technique to measure accurately gas molecule concentrations with a high temporal resolution. We determined that attenuation of sound amplitude varies in a manner dependent on the average molecular weight through which the sound wave passes. Based on this principle, we have designed a high-speed gas concentration sensor utilizing ultrasound. We investigated the practical potential of this sensor using a chemosensory stimulator (olfactometer); we succeeded in observing rapid gas exchange between air and nitrogen with a 2 kHz sampling rate. The signal/noise ratio of the stimulus was greater than 42 dB. In a 20 min experiment we determined that, for this olfactometer, the gas onset latency was 79 ms and the rise time was 16 ms. No significant artifact to magnetic fields was observed, even when the sensor was situated near a whole head magnetoencephalography (MEG) system. These results indicate that this sensor could be used for the observation of odor and air exchange, as well as, for real time monitoring of odor stimuli during actual experiments with a participant.

Suppression of BCR-ABL mRNA by various ribozymes in HeLa cells

Ribozymes are RNA molecules with enzymatic activity that can cleave target RNA molecules in a sequence specific manner. To date, various types of ribozyme have been constructed to cleave other RNAs and such trans-acting ribozymes include hammerhead, hairpin and HDV ribozymes. External guide sequence (EGS) can also induce the suppression of a gene-expression by taking advantage of cellular RNase P. Here we compared the activities of various functional RNA cleavers both in vitro and in vivo. The first purpose of this comparison was intended to determine the best ribozyme motif with the highest activity in cells. The second purpose is to know the correlation between the activities of ribozymes in vitro and in vivo. Our results indicated that the intrinsic cleavage activity of ribozymes is not the sole determinant that is responsible for the activity of a ribozyme in cultured cells.

Radiation-induced cerebral aneurysm successfully treated with endovascular coil embolization

In a 30-year-old male, multiple cerebral aneurysms developed 19 years after receiving 60 Gy of irradiation for craniophariginoma. Angiogram revealed right IC-PC and upper basilar trunk aneurysms in addition to atherosclerotic change. The right IC-PC aneurysm was wrapped and the basilar trunk aneurysm located between the origins of SCA and AICA was treated by endovascular coil embolization. The packing of the aneurysm was complete, but stenosis of the basilar artery appeared. The patient was discharged uneventfully and follow-up angiogram 6 months later demonstrated that the aneurysm had disappeared and the patency of the basilary artery had been preserved. Radiation-induced intracranial vasculopathy is a well-recognized phenomenon, but aneurysm formation is less common than arterial occlusive lesion. However, the mortality rate after bleeding is so high that immediate diagnosis and treatment by direct surgery or coil embolization are necessary.