Shunt flow of arteriovenous fistulas from plantar artery

Objective

The purpose of this study was to visualize the shunt flow of arteriovenous fistulas (AVFs) passing towards the top side of the foot from the plantar artery.

Methods

Colour-flow duplex Doppler ultrasonography was performed in 112 patients who consulted an outpatient clinic with varicose veins and/or symptoms such as foot oedema, dullness, cramp and coldness. Thirteen age-and sex-matched healthy subjects served as controls.

Results

AVFs were detected in 86 of 112 patients (77%). They were also detected in 10 (77%) of 13 healthy subjects. The shunt flow pattern consisted of two phases of flow corresponding to systole and diastole, and the diastolic fraction of time–velocity integral was larger, although the peak flow velocity in systole was higher than that in diastole.

Conclusion

Colour-flow duplex Doppler ultrasonography is useful for non-invasive visualization of the shunt flow of AVFs connecting the plantar artery with the venous arch of the top side of the foot.

Attitudes of medical professionals and transplantation facilities toward living-donor liver transplantation in Japan

The Japan Society for Transplantation (JST) revised their guidelines in 2003 to specify that a living donor must be "a relative by blood within the sixth degree or an in-law within the third degree." Although several criticisms have been raised on this issue, these criteria have persisted without any empirical data showing the opinions and attitudes of people who are affected by the revision. Therefore, we performed a questionnaire survey to determine what Japanese medical professionals involved with living-donor liver transplantation (LDLT) regarded as eligible relationships for donation, as well as the kind of relationship for which they would be willing to donate their liver, and what donor eligibility criteria was currently used by their institutions. Among the 71 representatives of the Japanese Liver Transplantation Society, >90% answered that liver donations to emotionally close parents, siblings, children, or spouses were acceptable. However, the numbers were considerably lower for donation to emotionally close blood relatives, in-laws, friends, and strangers (78.2%, 52.1%, 18.6%, and 5.9%, respectively). This gap was more prominent when participants were questioned about their own willingness to donate. More than two-thirds of facilities that perform LDLTs have independent regulations for donor eligibility that are more conservative than the JST guidelines. No facility accepted friends or strangers as donors. When introducing policies or guidelines, it is important to carefully investigate the views of the people who are affected. The data obtained in this study should serve as a resource for ongoing discussions about the JST revised guidelines.

Genetic and biochemical analyses of sensor kinase A in Bacillus subtilis sporulation

Temporal and spatial regulation of gene expression during endospore formation in Bacillus subtilis prompted us to investigate the molecular mechanisms that coordinate the phosphorelay. We targeted KinA for random mutagenesis. In addition, we constructed KinA-GFP transcriptional fusions for verification, via fluorescence. Four distinct types of sporulation-defective mutants were identified as inactive (no sporulation), hypoactive (low sporulation efficiency), isoactive (same efficiency as wild-type), and hyperactive (high efficiency) mutants. Surprisingly, the beta-galactosidase activity of hyperactive mutants was barely greater than that of the wild-type strain; the only noticeable difference was early synthesis of KinA, which could allow them to activate Spo0A precociously, undergo sporulation earlier, and yield more spores. There was no fluorescence emission by the spore-defective mutant, which confirmed the presence of a truncated KinA (nonsense mutation) in inactive strains; other mutants harbored missense or silent mutations. We determined the nucleotide sequences of KinA mutants and found a conserved C-terminus region; more variability was observed in the N-terminus region, involving the PAS-A and PAS-C domains. We speculate that PAS-A, notwithstanding its ATPase activity, has only a minor role in KinA activity, whereas PAS-B was found to be indispensable. Our results emphasize the importance of temporal coordination of gene expression during the sporulation process and corroborate the necessity of Spo0A phosphorylation by KinA, which stimulates SpoIIG expression. We further propose a novel hypothetical model that purposely dubbed the "C-shaped intertwined model", which requires both homodimerization and spatial proximity between PAS-A and histidine H(405) of two different KinA molecules.

Impaired host defence against Mycobacterium avium in mice with chronic granulomatous disease

Patients with chronic granulomatous disease (CGD), an inherited disorder of phagocytic cells, often contract recurrent life-threatening bacterial and fungal infections. CGD is considered to arise from a functional defect of the O(2)-generating nicotinamide adenine dinucleotide phosphate (NADPH) oxidase in phagocytes. To determine whether or not NADPH oxidase is crucial to the host defence against Mycobacterium avium, we investigated the response against M. avium using CGD model mice (gp91-phox(-)) of C57BL/6 strain. A tracheal injection of 1 x 10(7) colony-forming units (CFU)/head of M. avium strain FN into the CGD mice resulted in a pulmonary infection, while also increasing the mortality rate. In contrast, normal C57BL/6 mice injected with same dose of the organisms did not develop severe pulmonary infection and were able to survive through 2 months of observation. The macrophages obtained from the CGD mice were observed to have a higher burden of the bacterial growth than macrophages from normal C57BL/6 mice. These results suggest that the defect of the NADPH oxidase function impairs the host defence against M. avium infection.

Minimally invasive surgical treatment for tuberculous spondylodiscitis

The authors report the cases of 3 patients with tuberculous spondylodiscitis. All patients suffered from severe back or low back pain. Posterolateral endoscopic debridement and irrigation were performed followed by retention of a drainage tube at the affected sites. Additional puncture and drainage were conducted at the same time when extensive cold abscesses were identified around the paravertebral muscle. All patients experienced immediate pain relief postoperatively. This technique is effective for rapid pain relief and in obtaining neurological resolution for patients in the early stages of tuberculous spondylodiscitis and may also be a good method for preventing further vertebral collapse and kyphotic spinal deformity such as Gibbus vertebrae.

Temporal variation in maximum cell-specific nitrification rate

The cell numbers of ammonia-oxidising bacteria (AOBs), Nitrospira and Nitrobacter in activated sludge used to treat wastewater from a thermal power plant in Japan were examined for nine months using a real-time PCR quantification technique. AOB cell numbers ranged 2.8 x 10(10)-2.3 x 10(11) cell/L. The amoA clone analysis showed that the only Nitrosomonas halophila was responsible for ammonia oxidation over the period. Nitrospira were in the range of 2.6 x 10(9)-2.4 x 10(10) cell/L and Nitrobacter were less than 1% as common as Nitrospira. Meanwhile, maximum nitrification rates, maximum ammonia- and nitrite-oxidation rates obtained from aerobic batch tests, ranged 0.5-1.3 mmol-N/L h and 1.0-2.5 mmol-N/L h, respectively. No clear correlations were observed between the cell numbers of AOBs or Nitrospira and their maximum rates, because the maximum cell-specific ammonia- and nitrite-oxidation rates varied remarkably over the ranges of 1.1-11.9 and 2.4-21.6 fmol-N/cell h, respectively. To explore the factors controlling maximum cell-specific nitrification rates, the relationship to influent nitrogen loads per AOB or Nitrospira cell numbers was investigated. Fairly good correlations were obtained. Considering the effluent ammonia and nitrite concentrations were zero and only Nitrosomonas halophila had a role in ammonia oxidation over the period, we conclude that the amount of nitrogen oxidised per AOB or Nitrospira cell numbers likely controls maximum cell-specific ammonia- or nitrite-oxidation rates, respectively.

Visualizing CD4 T-cell migration into inflamed skin and its inhibition by CCR4/CCR10 blockades using in vivo imaging model

BACKGROUND

Chemokines are critical mediators of T-cell homing into inflamed skin. The complex nature of this multicellular response makes it difficult to analyse mechanisms mediating the early responses in vivo.

OBJECTIVES

To visualize directly T-cell homing into inflamed skin and its inhibition by blockades using a unique noninvasive confocal microscopy.

MATERIALS AND METHODS

A mouse model of allergic contact dermatitis was used. T cells from oxazolone-sensitized and -challenged Balb/c mice were first analysed phenotypically in vitro. CD4 T cells were then labelled with a tracker dye and transferred into Balb/c-SCID mice. The recipient mice were challenged with oxazolone and CD4 T-cell homing into inflamed skin was visualized.

RESULTS

T cells with the skin homing receptors CCR4 and CCR10 were increased in the affected skin and draining lymph nodes, and effectively attracted by their specific chemokines CCL17, CCL22 and CCL27 in vitro. Using in vivo imaging, T-cell migration into the inflamed skin was observed at 2 h after application, peaking at 12 h and continuing for 48 h. Simultaneous systemic administration of neutralizing antibodies against CCR4 ligands (CCL17 and CCL22) and CCR10 ligand (CCL27) led to a significant suppression of T-cell migration and skin inflammation.

CONCLUSIONS

Our data indicate that these tissue-selective adhesion molecules and chemokine/receptor pathways act in concert to attract specialized T-cell populations to mediate cutaneous inflammation. The in vivo imaging technique can be applicable to other models of cutaneous diseases to help with better understanding of the pathogenesis and monitoring the therapeutic effects.

Identification of oral species of the genus Veillonella by polymerase chain reaction

INTRODUCTION

Members of the genus Veillonella cannot be reliably distinguished by their biochemical characteristics and phenotypic features. Moreover, DNA-DNA hybridization and sequence analyses of the 16S ribosomal RNA gene including random fragment length polymorphism analysis, are complex and time-consuming procedures that are not well-suited to identifying oral species of Veillonella: Veillonella atypica, Veillonella denticariosi, Veillonella dispar, Veillonella parvula, and Veillonella rogosae.

METHODS

In this study, five forward primers and a reverse primer were designed for polymerase chain reaction (PCR) according to the partial sequences of the rpoB genes of these oral Veillonella species.

RESULTS

The forward primers were species-specific for these five Veillonella species, and could produce specific amplicons when used together with reverse primer and individual DNA templates of these species in PCR. These primer pairs were also found to discriminate between the respective species, and the Veillonella strains isolated from human oral cavities were successfully assigned to one of the five oral species of the genus Veillonella based on their specific products by PCR.

CONCLUSION

A simple two-step PCR procedure using the five sets of primer pairs developed in the present study is a rapid and reliable method for the identification of the recognized oral Veillonella species.

Gangliosides' protection against lysosomal pathology of synucleinopathies

Gangliosides are abundantly expressed in the nervous system, and deregulated expression or activity of gangliosides is associated with the progression of various disorders, including lysosomal storage diseases, Guillain-Barre syndrome and Alzheimer disease. By contrast, previous studies show that GM1 ganglioside may act in a protective manner in the drug (e.g., MPTP and 6-OHDA)-induced Parkinsonian models, although the precise mechanisms have not been well addressed. In our recent publication, dementia with Lewy bodies (DLB)-linked neuroblastoma cells were treated with D-Threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP), an inhibitor of glycosyl ceramide synthetase. These PDMP-treated cells develop lysosomal diseases characterized by reduced lysosomal activity, enhanced lysosomal permeability and cytotoxicity. Furthermore, PDMP-mediated inhibition of autophagy-lysosomal pathway result in both accumulation of alpha-synuclein and mutant beta-synuclein. Finally, these phenotypes are reversed by ganglioside treatment. Taken together, our results suggest that endogenous gangliosides may play a protective role against the lysosomal pathology of synucleinopathies.

Alpha-synuclein overexpression and aggregation exacerbates impairment of mitochondrial functions by augmenting oxidative stress in human neuroblastoma cells

Overexpression of alpha-synuclein and oxidative stress has been implicated in the neuronal cell death in Parkinson's disease. Alpha-synuclein associates with mitochondria and excessive accumulation of alpha-synuclein causes impairment of mitochondrial functions. However, the mechanism of mitochondrial impairment caused by alpha-synuclein is not fully understood. We recently reported that alpha-synuclein associates with mitochondria and that overexpression of alpha-synuclein causes nitration of mitochondrial proteins and release of cytochrome c from the mitochondria [Parihar M.S., Parihar A., Fujita M., Hashimoto M., Ghafourifar P. Mitochondrial association of alpha-synuclein causes oxidative stress. Cell Mol Life Sci. 2008a;65:1272-1284]. The present study shows that overexpression of alpha-synuclein A53T or A30P mutants or wild-type in human neuroblastoma cells augmented aggregation of alpha-synuclein. Immunoblotting and immuno-gold electron transmission microscopy show localization of alpha-synuclein aggregates within the mitochondria of overexpressing cells. Overexpressing cells show increased mitochondrial reactive oxygen species, increased protein tyrosine nitration, decreased mitochondrial transmembrane potential, and hampered cellular respiration. These findings suggest an important role for mitochondria in cellular responses to alpha-synuclein.

Acute Chlamydia pneumoniae infection in the pathogenesis of autoimmune diseases

Autoimmune diseases have several etiologies. Acute Chlamydia pneumoniae (C. pneumoniae) infection may be involved in the pathogenesis of several autoimmune diseases. In this study, 82 patients with several autoimmune diseases and 70 controls were enrolled, and acute C. pneumoniae infection has been evaluated by monitoring the levels of IgM antibody. Chlamydia pneumoniae IgM positive results were observed in 29% (P < 0.05) of the patients with several autoimmune diseases and in 10% of the controls. Chlamydia pneumoniae IgM positive cases were more frequent among the patients with rheumatoid arthritis (RA; 30%, P < 0.05), systemic lupus erythematosus (SLE; 28.0%, P < 0.05), dermatomyositis/polymyositis (23%, NS), myeloperoxidase-antineutrophil cytoplasmic autoantibody (MPO-ANCA)-associated vasculitis (33%, NS), adult onset of Still's disease (29%, NS) and giant cell arteritis/Takayasu arteritis (50%, NS) than among the controls. This positive frequency was statistically significant in RA and SLE. These results suggest that acute C. pneumoniae infection is probably involved in the pathogenesis of autoimmune diseases.

Charge excitations in the stripe-ordered La5/3Sr1/3NiO4 and La2-x(Ba,Sr)xCuO4 superconducting compounds

Charge excitations in stripe-ordered 214 compounds La_{5/3}Sr_{1/3}NiO_{4} and 1/8-doped La2-x(Ba or Sr)xCuO4 are studied using resonant inelastic x-ray scattering in the hard x-ray regime. We observe = or approximately 1 eV excitation with a momentum transfer corresponding to the charge stripe spatial period both for the diagonal (nickelate) and parallel (cuprates) stripes. They are interpreted as collective stripe excitations or anomalous softening of the charge excitonic modes of the in-gap states.

Protective role of endogenous gangliosides for lysosomal pathology in a cellular model of synucleinopathies

Gangliosides may be involved in the pathogenesis of Parkinson's disease and related disorders, although the precise mechanisms governing this involvement remain unknown. In this study, we determined whether changes in endogenous ganglioside levels affect lysosomal pathology in a cellular model of synucleinopathy. For this purpose, dementia with Lewy body-linked P123H beta-synuclein (beta-syn) neuroblastoma cells transfected with alpha-synuclein were used as a model system because these cells were characterized as having extensive formation of lysosomal inclusions bodies. Treatment of these cells with D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP), an inhibitor of glycosyl ceramide synthase, resulted in various features of lysosomal pathology, including compromised lysosomal activity, enhanced lysosomal membrane permeabilization, and increased cytotoxicity. Consistent with these findings, expression levels of lysosomal membrane proteins, ATP13A2 and LAMP-2, were significantly decreased, and electron microscopy demonstrated alterations in the lysosomal membrane structures. Furthermore, the accumulation of both P123H beta-syn and alpha-synuclein proteins was significant in PDMP-treated cells because of the suppressive effect of PDMP on the autophagy pathway. Finally, the detrimental effects of PDMP on lysosomal pathology were significantly ameliorated by the addition of gangliosides to the cultured cells. These data suggest that endogenous gangliosides may play protective roles against the lysosomal pathology of synucleinopathies.

The activation of P2X7 receptor impairs lysosomal functions and stimulates the release of autophagolysosomes in microglial cells

Recently, autophagy has been associated with the TLR signaling pathway to eliminate intracellular pathogens in the innate immune system. However, it is unknown if other pathways regulate autophagy during the immunologic response. Given the critical role of the purinergic P2X7 receptor (P2X7R) pathway during various immunologic functions (i.e., caspase activation and IL-1beta secretion), the principal objective here was to determine whether the P2X7R pathway may regulate autophagy in immune cells. We observed in both MG6 mouse microglial cells and primary microglia that activation of P2X7R by ATP increases the expression of microtubule-associated protein 1 light chain 3 (LC3)-II, the autophagosomal membrane-associated form of LC3, in an extracellular Ca(2+)-dependent manner. Consistent with this, immunohistochemistry showed extensive formation of LC3-immunopositive dots, and electron microscopy demonstrated accumulation of autophagosomes and autophagolysosomes in ATP-treated cells. Importantly, the up-regulation of LC3-II by P2X7R activation was not affected by autophagy inhibitors, such as 3-methyladenine and PI3K inhibitors. Furthermore, while lysosomal functions were impaired by ATP treatment, autophagolysosomal components were released into the extracellular space. Similarly, a phagocytosis assay using Escherichia coli BioParticles showed that phagosome maturation was impaired in ATP-treated cells and a robust release of LC3-immunopositive phagolysosomes was induced along with a radial extension of microtubule bundles. Taken together, the data suggest a novel mechanism whereby the P2X7R signaling pathway may negatively regulate autophagic flux through the impairment of lysosomal functions, leading to stimulation of a release of autophagolysosomes/phagolysosomes into the extracellular space.

Microglial activation is inhibited by corticosterone in dopaminergic neurodegeneration

The present study compared 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced microglial activation in 3 different groups, sham-operated (SHM) mice, adrenalectomized mice (ADX), and ADX mice administered with corticosterone (ADX + CORT), to investigate the roles of glucocorticoids on microglial activation and dopaminergic neurodegeneration. Acute MPTP treatment induced moderate tyrosine hydroxylase (TH)-immunoreactive neuronal loss in the substantia nigra (SN) of SHM mice; this neuronal loss was significantly enhanced in ADX mice, but eventually recovered following the administration of corticosterone. Consistent with neuronal findings, acute MPTP treatment induced microglial activation in the SN from 1-3 days post injection in SHM mice. Interestingly, microglial activation was further enhanced and occasionally showed a phagocytic morphology in ADX mice that showed no circulating corticosterone. Furthermore, the activated microglia was significantly suppressed by the administration of corticosterone to ADX mice. Moreover, a confocal microscopic study demonstrated that the expression of inducible nitric oxide synthase protein, exclusively colocalized with activated microglia in the SN in ADX mice, was substantially decreased by the administration of corticosterone. Thus, the present study, using in-vivo adrenalectomy for a dopaminergic neurodegeneration model, successfully demonstrated the neuroprotective effects of corticosterone by microglial inhibition.

Determinants of collateral development in patients with acute myocardial infarction

BACKGROUND

The presence or absence of collateral circulation to the infarct-related coronary artery in acute myocardial infarction (AMI) significantly impacts on infarct size and resulting left ventricular function. However, the determinants of collateral development have not been clarified.

HYPOTHESIS

The purpose of this study was to elucidate the determinants of collateral development in humans.

METHODS

The study group consisted of 248 patients (178 men, 70 women; mean age 63 years) undergoing coronary angiography within 12 h after the onset of a first AMI. All patients exhibited complete occlusion of the infarct-related artery. The extent of collateral circulation to the area perfused by the infarct-related artery was graded as none, or poorly or well developed, depending on the degree of opacification of the occluded coronary artery on the contralateral injection of contrast.

RESULTS

Well-developed collateral circulation was observed in 92 of the 248 patients (37.1%). The prevalence of well-developed collaterals was 57% in patients with a history of angina pectoris prior to AMI, which was significantly (p < 0.0001) higher than the 26% in those without a history of angina. Multivariate stepwise logistic regression analysis was then applied to identify predictors of collateral development. Possible determinants of collateral development were long-standing preinfarction angina, severity of coronary artery disease, age, gender, and coronary risk factors (hypertension, diabetes, hypercholesterolemia, smoking). This analysis revealed that only the presence of a history of angina pectoris prior to AMI was a significant predictor of collateral development (p < 0.0001).

CONCLUSIONS

A history of angina pectoris prior to AMI is a clinical marker for coronary stenoses. Since severe coronary stenoses can provide stimuli that lead to collateral development, it is reasonable that a history of angina would also be a clinical marker for collateral vessels.

Importance of alpha 1-sympathetic activity for diurnal change in ischemic threshold in patients with stable angina

BACKGROUND

Although ischemic threshold reportedly is lower in the early morning than in the afternoon, the mechanisms that account for the diurnal change in minimal coronary vascular resistance in the potentially ischemic area are unknown.

HYPOTHESIS

We hypothesized that calcium-channel blockers and alpha 1 blockers may affect the ischemic threshold in the early morning and afternoon in patients with stable angina.

METHODS

Before and after the administration of the calcium antagonist amlodipine (5 mg) alone and combined with the alpha 1 blocker prazosin (1 mg), a treadmill exercise test using the Balke-Ware protocol was undertaken in the morning (8:00 A.M.) and repeated in the afternoon (1:00 P.M.) with 15 stable angina patients. The ischemic threshold was defined as a reciprocal of minimal coronary vascular resistance in the presence of comparable levels of myocardial ischemia indicated by 0.1 mV ST depression. Minimal coronary vascular resistance was calculated as mean blood pressure divided by coronary blood flow. Since the coronary blood flow is closely related to myocardial oxygen consumption, which can be replaced by the double product of heart rate and systolic blood pressure, minimal coronary vascular resistance was approximated to 1/heart rate.

RESULTS

At baseline, minimal coronary vascular resistance was significantly higher in the early morning than in the afternoon (8.5 +/- 0.3 x 10(-3) min/beats vs. 7.8 +/- 0.4 x 10(-3) min/beats, p < 0.01). Although treatment with amlodipine alone did not abolish the circadian pattern of minimal coronary vascular resistance (8.0 +/- 0.6 x 10(-3) min/beats vs. 7.7 +/- 0.6 x 10(-3) min/ beats, p < 0.05), the addition of prazosin virtually eliminated the diurnal difference in minimal coronary vascular resistance (7.4 +/- 0.5 x 10(-3) min/beats vs. 7.5 +/- 0.5 x 10(-3) min/beats, p = NS).

CONCLUSIONS

These findings indicate that alpha 1-sympathetic activity may play a role in the pathogenesis of the diurnal change of ischemic threshold in patients with stable angina.

Hidden quantum spin-gap state in the static stripe phase of high-temperature La2-xSrxCuO4 superconductors

Low-energy spin excitations were investigated in the static stripe phase of La2-xSrxCuO4 using elastic and inelastic neutron scattering on single crystals. For x=1/8 in which long-range static stripe order exists, an energy gap of E(g)=4 meV exists in the excitation spectrum in addition to strong quasielastic, incommensurate spin fluctuations associated with the static stripes. When x increases, the spectral weight of the spin fluctuations shifts from the quasielastic continuum to the excitation spectrum above E(g). The dynamic correlation length as a function of energy and the temperature evolution of the energy spectrum suggest a phase separation of two distinct magnetic phases in real space.

Evaluation of biodegradation potential of organic compounds by river water microorganisms

The aim of this study was to assess the availability of the biodegradation potential of aniline and phenol as the indicator for evaluating pollutant impact on a river environment. Biodegradation tests employing river water microorganisms were carried out by a modified TOC-Handai method using aniline and phenol as substrates. Complete degradation time and half-life were determined as indicators expressing the biodegradation potential of aniline and phenol, respectively. Investigations in Lake Biwa-Yodo River basin for more than two years showed that the biodegradation potential of both compounds varied seasonally. In addition, aniline biodegradation potential seemed to be influenced by the hydraulic retention time at each sampling station, while downstream stations with large input of wastewater from the surrounding cities were divided from upstream stations by phenol biodegradation potential. Comparison of the biodegradation potential in rivers at different pollution levels also showed that polluted and less polluted rivers were clearly divided by phenol biodegradation potential. These results indicated that phenol biodegradation potential can be applied as an indicator for evaluating the soundness of river environment from the view point of ecological function.

Acetate uptake efficiency of polyphosphate-accumulating organisms under exposure to surfactants

We investigated the influence of surfactants such as linear alkylbenzene sulfonates (LAS) and alcohol ethoxylates (AE) on acetate uptake by polyphosphate-accumulating organisms (PAOs) under anaerobic conditions, using the phosphate requirement for acetate uptake (+DeltaP/-DeltaAc ratio). In order to estimate the +DeltaP/-DeltaAc ratio, anaerobic batch tests were conducted using activated sludge collected from an anaerobic/oxic sequencing batch reactor used to treat municipal wastewater continuously supplemented with a detergent containing LAS and AE. We demonstrated that LAS and AE have both positive and negative impacts on acetate uptake by PAOs. The disadvantage is that long-term exposure to the detergent inhibits acetate uptake by PAOs, thus deteriorating the efficiency, even if the surfactants are no longer present during the tests. Furthermore, the existence of LAS and/or AE with acetate further diminishes the efficiency. The advantage is that LAS and AE are potential sources of polyhydroxyalkanoate for PAOs, because acetate is produced from the surfactants under anaerobic conditions.

Differential microglial activation between acute stress and lipopolysaccharide treatment

Acute stress was demonstrated to induce morphological microglial activation in several brain regions including the midbrain periaqueductal gray (PAG), an area that plays important roles in behavioral responses to uncontrollable stress, threat, anxiety, and pain. To determine whether neuronal activation may be involved in the stress-induced microglial activation, the present study investigated the correlation between neuronal activity measured as c-Fos expression and morphological microglial activation in the PAG. Acute stress was followed by morphological activation of microglia and increased c-Fos expression in the PAG but not in the surrounding midbrain. Double immunohistochemistry and topological analysis demonstrated that microglial activation occurred adjacent to responsive neurons. By contrast, lipopolysaccharide (LPS) treatment induced microglial activation even in the absence of neuronal responses in the PGA as well as in the rest of the midbrain. These findings suggest that the mechanism of microglial activation during stress may differ from those of infection or inflammation. It also indicates that the neuronal cells expressing c-Fos protein may play some roles to trigger microglial activation.

Magnetic dispersion of the diagonal incommensurate phase in lightly doped La2-xSrxCuO4

We present inelastic neutron scattering experiments on a single-domain crystal of lightly doped La1.96Sr0.04CuO4. We find that the magnetic excitation spectrum in this insulating phase with a diagonal incommensurate spin modulation is remarkably similar to that in the superconducting regime, where the spin modulation is bond parallel. In particular, we find that the dispersion slope at low energy is essentially independent of doping and temperature over a significant range. The energy at which the excitations cross the commensurate antiferromagnetic wave vector increases roughly linearly with doping through the underdoped regime.

Low-energy spin fluctuations in the ground states of electron-doped Pr1-x LaCexCuO4+delta cuprate superconductors

Low-energy spin fluctuations have been investigated in the electron-doped Pr{1-x}LaCe{x}CuO{4+delta} over a wide concentration range of 0.07<or=x<or=0.18, spanning from the antiferromagnetic phase to the heavily overdoped superconducting (SC) phase. The low-energy excitations exhibit commensurate peaks centered at the (pi, pi) position for all x. Our data show that the characteristics of the excitations, such as the relaxation rate and the spin stiffness, decrease with increasing x in the SC phase and disappear with the disappearance of superconductivity.

Application of real-time polymerase chain reaction (PCR) coupled with ethidium monoazide treatment for selective quantification of viable bacteria in aquatic environment

Ethidium monoazide (EMA) was used to quantify DNA selectively from viable cells with healthy membrane/cell wall system, but not from dead cells, of a target bacterium in the aquatic environment using real-time PCR. Spiking experiments to determine the EMA treatment conditions showed that EMA treatment with EMA at 10-25 microg/ml and subsequent halogen light exposure for 2 min was suitable for selective quantification of DNA from viable cells in an aquatic sample using real-time PCR coupled with EMA treatment (real-time EMA-PCR). Optimized real-time EMA-PCR was applied in combination with culture-based method and conventional real-time PCR without EMA treatment to elucidate the behavior of an Escherichia coli strain inoculated into a pond water microcosm. Quantification results obtained using real-time EMA-PCR were lower than those by conventional real-time PCR without EMA treatment and higher than those by culture-based method. The results suggest that quantification by real-time EMA-PCR seemed to represent the viable population, which would partly include viable but non-culturable state bacteria. Real-time EMA-PCR optimized here can be a useful tool for selective monitoring of the viable population of a target bacterium in the aquatic environment, and thereby contribute to assessment of potential microbial risks generated from waterborne pathogenic bacteria.