Use of real-time PCR to examine the relationship between ammonia oxidizing bacterial populations and nitrogen removal efficiency in a small decentralized treatment system 'Johkasou'

The aim of this study was to examine the relationship between ammonia oxidizing bacterial populations and biological nitrogen removal in a small on-site domestic wastewater treatment system "Johkasou". The population dynamics of ammonia oxidizing bacteria (AOB) in six full-scale advanced Johkasous was surveyed using real-time PCR assay over a period of one year. These Johkasous were selected to compare the AOB populations in different treatment performance. When the effluent NH4-N concentration was higher than 2 mg L(-1), it was difficult to meet the effluent standard of advanced Johkasous (T-N 10 mg L(-1)). In contrast, the nitrogen removal efficiency was hardly affected by nitrite oxidation and denitrification in these systems. In other words, ammonia oxidation was a rate-limiting step. Furthermore, we focused on the relationship between NH4-N loading per AOB cell and nitrogen removal. Real time PCR monitoring results demonstrated that it is important to regulate NH4-N loading per AOB cell below 210 pg cell(-1) day(-1) to meet the effluent standard of advanced Johkasou. It is considered that NH4-N loading per AOB cell is a useful parameter for determining suitable nitrogen loading and small decentralized system design.

Gastric cancer among peptic ulcer patients: retrospective, long-term follow-up

BACKGROUND

Patients with duodenal ulcer are not at high risk although Helicobacter pylori infection is no doubt associated with gastric cancer development. However, little is known about the risk after long-term follow-up.

AIMS

We investigated the incidence for gastric cancer development in peptic ulcer patients in a long term.

PATIENTS AND METHODS

Between 1965 and 2004, endoscopic follow-up of more than 1 year was conducted on 1504 peptic ulcer patients in our hospital. They consisted of 978 gastric ulcer patients, 444 duodenal ulcer patients and 82 gastric and duodenal ulcer patients. Gastric and duodenal ulcer patients were excluded from the analysis because of their limited number.

RESULTS

Gastric cancers developed in 32 (3.3%) of gastric ulcer patients and 3 (0.68%) of duodenal ulcer patients. Kaplan-Meier analysis showed that the incidence of gastric cancer in duodenal ulcer patients was significantly lower than that in gastric ulcer patients (log-rank test, p=0.0059). Cox's proportional hazard model denoted the relative risk for duodenal ulcer against gastric ulcer adjusted by sex and age as 0.23 (95% CI: 0.072-0.77, p=0.016).

CONCLUSION

The risk for patients with duodenal ulcer to develop gastric cancer over the long term is significantly less than in those with gastric ulcer.

Study on the relationship of protease production and luminescence in Vibrio harveyi

AIMS

To demonstrate that Vibrio harveyi produces various types of toxins and how the production of those toxins is related with luminescence.

METHODS AND RESULTS

Luminescence and toxicity of eight V. harveyi were evaluated. We demonstrated that all V. harveyi emitting luminescence were isolated from marine organisms and also showed that they were highly pathogenic when compared with culture collection V. harveyi based on cytotoxic assay test. On the contrary, V. harveyi isolated from shrimp farm showed no luminescence but showed high pathogenicity based on toxicity test. The effect of protease inhibitors on pathogenicity and luminescence was also investigated. We demonstrated that light emission of pathogenic V. harveyi remarkably decreased after addition of protease inhibitor. Furthermore, extracellular proteins from cell-free culture supernatant of luminescent and nonluminescent V. harveyi were compared using SDS-PAGE analysis. Results showed that there were differences in molecular weight and amount of proteins.

CONCLUSIONS

Vibrio harveyi parasiting marine organisms have both luminescence and pathogenicity. Based on this study, luminescence and protease toxin activity in V. harveyi are related. Moreover, this paper clarified that V. harveyi produces various types of toxins.

SIGNIFICANCE AND IMPACT OF THE STUDY

The current study demonstrated that V. harveyi produces two kinds of toxins, haemolysin and protease toxin. It may be clear roots of V. harveyi toxin.

[Unusual total anomalous pulmonary venous connection; report of a case]

We report a case of a 7-hour-old infant with total anomalous pulmonary venous connection having abberant origin of the vertical vein. His clinical condition presented hemodynamically severe pulmonary vein obstruction as common pulmonary vein atresia. Without making the definitive diagnosis, he underwent the operation at 11 hours after birth under cardiopulmonary bypass. During the operation, we could not identify the drainage vein. Although we ligated the vessel sized less than 2 mm in diameter draining into superior vena cava which was suspected to be the vertical vein. After the operation pulmonary edema was severe, but his clinical condition improved by using nitric oxide without extracorporeal membrane oxygenation (ECMO) support. Postoperative cardiac catheterization showed normal cardiac function without pulmonary venous obstruction, and moreover identified the drainage vein originated from right upper pulmonary vein. To the best of our knowledge, this is the first case where the vertical vein originated from right upper pulmonary vein. Immediate surgical treatment before the circuratory exacerbation improve the outcome for this congenital anomaly.

Locations of congenital cholesteatoma in the middle ear in Japanese patients

OBJECTIVES

To present clinical features of congenital cholesteatoma treated in our institute and to investigate the locations of congenital cholesteatoma in the middle ear of Japanese patients to verify its pathogeneses.

PATIENTS AND METHODS

A retrospective chart review of patients in our institute and a review of articles on congenital cholesteatoma reported by Japanese researchers. Charts of the 25 patients with congenital cholesteatoma treated in our institute were reviewed regarding symptoms, locations of cholesteatoma in the middle ear, and ossicular anomalies. The same points were investigated in the 71 cases in the Japanese literature.

RESULTS

Unlike Westerners, more than half of the Japanese cases had posterior-type cholesteatomas, any parts of which did not exist anteriorly beyond the handle of the malleus. Congenital ossicular anomalies, absence of the long process of the incus, and/or the superior structure of the stapes were seen with a high rate in the Japanese patients.

CONCLUSIONS

These two findings of the posterior location of cholesteatomas in the middle ear and the high incidence of congenital ossicular anomalies in the Japanese patients suggested that there should be some racial difference in pathogenesis of congenital cholesteatoma. The pathogenesis of congenital cholesteatoma cannot be adequately explained by only one theory alone. It is more appropriate to explain the pathogenesis by using an aggregation of theories.

Improvement of treatment efficiency of thermophilic oxic process for highly concentrated lipid wastes by nutrient supplementation

The biodegradation of highly concentrated lipid wastes was conducted by a thermophilic oxic process (TOP). In order to improve the treatment efficiency of TOP, the stimulatory effect of nutrient supplementation was examined. A model nutrient supplement that satisfied the essential components necessary to promote degradation of lipid wastes was developed. The importance of balanced nutrient supplement consisting of organic and inorganic components was demonstrated. Regardless of the source of either vegetable oil or animal fat, the combination of 1.5 g of yeast extract, 1 g of urea and 60 ml of trace-element solution was effective to stimulate the degradation of 15 g of lipids by TOP. With this combination, degradation efficiencies of 68% and 77% in a 120-h treatment were attained for salad oil and lard, respectively. The conversion ratio of degraded lipid materials to CO2 was 0.91, confirming the advantage of TOP, i.e., very low excess sludge generation. The effectiveness of the model nutrient supplement for stimulating the degradation of lipid materials by TOP was also confirmed when tested on three kinds of actual highly concentrated lipid wastes. A constant degradation efficiency of around 60% in a 120-h treatment was attained for all lipid wastes although further improvement of degradation efficiency was possible by some nutrient addition into the model supplement combination. Based on the model nutrient supplement, the essential components for stimulating oil degradation by TOP and the possible alternative materials for the model nutrient supplement were discussed. The results demonstrated the possibility of employing TOP (stimulated by nutrient supplement) as a new biological treatment strategy for highly concentrated lipid wastes.

Retinal neovascularisation without ischaemia in the spontaneously diabetic Torii rat

AIMS/HYPOTHESIS

The spontaneously diabetic Torii (SDT) rat has recently been established as a model of type 2 human diabetes mellitus. Male SDT rats develop severe diabetic ocular complications. This study investigated the nature of the ocular complications in this model and addressed the question of whether the SDT rat is a good model of human proliferative diabetic retinopathy.

METHODS

Male SDT rats aged 50 weeks were studied for a period of 8 months. Under deep anaesthesia, one eye of each animal was enucleated following perfusion with fluorescein dextran and a retinal flat mount was prepared to study vascular structure. The other eye was enucleated and investigated histologically by haematoxylin-eosin and azan staining and by immunohistochemistry using antibodies against vascular endothelium (Griffonia simplicifolia isolectin B4 antibody) and vascular endothelial growth factor (VEGF).

RESULTS

From the vascular structure study, 17 of 32 rats (53%) showed proliferative retinopathy without vascular non-perfusion. The histological study revealed traction retinal folds in rats with proliferative retinopathy. Azan staining showed some proliferative matrix in rats with normal retinal structure and those with proliferative retinopathy compared with normoglycaemic controls. Staining with Griffonia simplicifolia isolectin B4 antibody showed no specific vascular changes in any of the rats, while VEGF staining revealed higher immunoreactivity in the retina of rats with normal retinal structure and those with proliferative retinopathy, but only low immunoreactivity in the control animals.

CONCLUSIONS/INTERPRETATION

There appear to be differences between the SDT rat model of diabetic retinopathy and human proliferative diabetic retinopathy, as the SDT rat develops retinal neovascularisation without retinal ischaemia. This very unique display of ocular neovascularisation may be caused by increased expression of VEGF.

Two cases of recurrent IgA nephropathy following kidney transplantation

Recurrence of immunoglobulin (Ig) A nephropathy following kidney transplantation has been described as occurring in 40% to 60% of cases. Although this type of recurrence was considered a benign condition for a long time, more recent data showed that recurrent transplant IgA nephropathy may be a significant contributor to graft loss. We present 2 cases of recurrent IgA nephropathy following kidney transplantation. In case 1, renal function remained stable with a creatinine level of 1.2 mg/dL at 5 months after diagnosis and 61 months after transplantation. In case 2, the patient lost his graft and returned to regular hemodialysis at 36 months after diagnosis and 125 months after kidney transplantation.

Optic nerve compression by normal carotid artery in patients with normal tension glaucoma

AIM

To determine whether compression of the optic nerve by the intracranial carotid artery (ICA) can be a causative factor of normal tension glaucoma (NTG).

METHODS

The medical records of 103 eyes of 54 Japanese patients with NTG and 104 eyes of 52 age matched control patients were reviewed. The neuroradiological findings of magnetic resonance images (MRI) were evaluated to determine the relation between the optic nerve and ICA. The clinical characteristics and general medical conditions, such as diabetes and systemic hypertension, were also compared between the two groups.

RESULTS

The prevalence of optic nerve compression by the ICA in patients with NTG was 49.5%, which was significantly higher than that in control group with 34.6% (p = 0.035). Bilateral compression of the optic nerve was detected in 22 patients with NTG (40.7%), and this was also significantly higher (p = 0.029) than that in the control group (11 patients, 21.2%). In the NTG group, eyes with cup/disc ratio (C/D ratio) > or =0.7 showed a higher percentage of compression (52.6%) compared with eyes with C/D ratio of <0.7 (12.5%; p = 0. 042). The presence of diabetes and hypertension did not affect the incidence of optic nerve compression by ICA significantly.

CONCLUSIONS

The significantly higher percentage of NTG patients who had optic nerve compression by the ICA suggests that compression of the optic nerve by ICA may be a possible causative factor or a risk factor for optic nerve damage in some patients with NTG.

Effects of FTY720 on rat lymphoid organs

INTRODUCTION

In this study, we examined the in vivo effect of FTY720 on rat thymus and spleen.

MATERIALS AND METHODS

Inbred male Lewis (RT-I(l)) rats, 5-weeks-old, received FTY720 (0.1, 1, or 10 mg/kg) by intramuscular injection into 1 of 4 limbs daily for 7 days. The rats were humanely killed at 1, 3, 5, or 7 days after starting administration of FTY720. The thymus and spleen were obtained for hematoxylin and eosin (HE) as well as immunoperoxidase staining using the antibodies OX8 (CD8), W3/25 (CD4), and OX6 (major histocompatibility complex class II).

RESULTS

HE staining revealed marked atrophy in the cortical region of the thymus among rats administered FTY720 at the dose of 10 mg/kg. The atrophy extended to the whole cortex. On day 7 of administration of FTY 720 (10 mg/kg), the medulla of the thymus showed relative expansion due to cells accumulation. Also, the spleens of FTY720-treated rats revealed an obvious reduction in the T-cell-dependent areas around the central artery. In conclusion, the immunosuppressive effect of FTY720 may be due to an inhibitory effect on T-cell emigration from the thymus to the periphery.

Expression of pigment epithelium derived factor and vascular endothelial growth factor in choroidal neovascular membranes and polypoidal choroidal vasculopathy

AIMS

To determine whether pigment epithelium derived factor (PEDF), a protein that inhibits angiogenesis, is expressed in human choroidal neovascular membranes (CNVMs) and in tissues from an eye with polypoidal choroidal vasculopathy (PCV). In addition, to compare the expression of PEDF with that of vascular endothelial growth factor (VEGF), a known stimulator of angiogenesis, in these tissues.

METHODS

CNVMs, associated with age related macular degeneration (AMD), angioid streaks, and PCV, were obtained during surgery. The expression of PEDF and VEGF in the excised subretinal fibrovascular membranes was determined by immunohistochemistry.

RESULTS

PEDF and VEGF were strongly expressed in the vascular endothelial cells and retinal pigment epithelial (RPE) cells in the CNVMs where numerous new vessels were prominent (clinically active CNVMs). On the other hand, immunoreactivity for PEDF and VEGF was weak in the new vessels where fibrosis was prominent (clinically quiescent CNVMs). However, the RPE cells were still positive for PEDF and VEGF. The specimens from the eye with PCV also showed strong expression of PEDF and VEGF in the vascular endothelial cells and the RPE cells.

CONCLUSION

Because PEDF is an inhibitor of ocular angiogenesis and an inhibitor of ocular cell proliferation, our results suggest that PEDF along with VEGF may modulate the formation of subfoveal fibrovascular membranes.

The efficacy of Burow's solution as an ear preparation for the treatment of chronic ear infections

OBJECTIVE

To determine the efficacy of Burow's solution as an otologic preparation for the treatment of chronic ear infection.

STUDY DESIGN

Two studies were included: 1) a prospective clinical study and 2) a laboratory study on antibacterial and antifungal effects.

SETTING

A private otology practice and a laboratory study.

PATIENTS

Fifty-eight patients with refractory otorrhea.

INTERVENTION

Diagnosis by otoscopy, audiometry, and bacteriology.

METHODS

Burow's solution was mixed in solutions with four organisms: methicillin-resistant Staphylococcus aureus, penicillin-resistant Streptococcus pneumoniae, Candida albicans, and Aspergillus. Soon after Burow's solution was mixed in the solutions with organisms, and 5, 10, and 20 minutes thereafter, the mixtures were cultured on agars. The numbers of the bacterial or fungal colonies were counted to evaluate the effect of Burow's solution.

MAIN OUTCOME MEASURES

Changes in the clinical findings of the ears, the symptom of otorrhea, and side effects were assessed.

RESULTS

Thirty-five (70%) of the 50 ears assessed were "cured" and 10 (20%) ears assessed were "improved." No significant side effect was observed. Regarding the laboratory study, the four organisms disappeared within 20 minutes after Burow's solution was mixed.

CONCLUSION

Burow's solution was considered to be an effective otologic preparation.

Improved simultaneous nitrification and denitrification in a single reactor by using two different immobilization carriers with specific oxygen transfer characteristics

To maximize nitrogen utilization rates during nitrification and denitrification in a simultaneous reaction for direct nitrogen removal from ammonia-nitrogen in a single reactor, two different carriers were applied that immobilized nitrifiers and denitrifiers separately. With the optimized DO concentration and mixing ratio of immobilization carriers, ammonium-nitrogen was successfully removed as designed until the middle phase of treatment where nitrogen removal rate was higher than 83% of the theoretical value, although an imbalance between nitrification and denitrification occurred at a later phase of treatment where residual nitrate-nitrogen concentration was less than 2 mg/l. The new approach using two different carriers to immobilize nitrifiers and denitrifiers separately was proved useful for controlling both nitrification and denitrification rates, enabling the utilization of maximum treatment ability of both nitrifiers and denitrifiers in a single reactor for direct nitrogen removal from ammonium-nitrogen.

Comparative analysis of genetic diversity and expression of amoA in wastewater treatment processes

The genetic diversity and expression of amoA of autotrophic ammonia oxidizers in wastewater treatment processes were investigated by RT-PCR and denaturing gradient gel electrophoresis (DGGE) in order to identify active components of ammonia-oxidizer populations in a such processes. Ammonia oxidizers, evidenced by the presence of amoA mRNA, were regarded as metabolically active. The DGGE profiles derived from amoA mRNA and from its gene, which were amplified by RT-PCR or PCR using samples collected from a bench-scale reactor treating high concentration of inorganic ammonia, were similar. In contrast, RNA and DNA-derived DGGE profiles from three domestic wastewater treatment facilities were different from each other. These data indicate that the dominant ammonia oxidizers in the bench-scale reactor exhibited ammonia-oxidizing activity, whereas some ammonia oxidizers in the domestic wastewater treatment facilities apparently did not express high levels of amoA mRNA.

The proportion of cells with functional X disomy is associated with the severity of mental retardation in mosaic ring X Turner syndrome females

Turner syndrome females (45,X) do not have mental retardation (MR), whereas some mosaic ring X Turner syndrome females, with 45,X/46,X,r(X), have severe MR. The MR is believed to be caused by a failure of X chromosome inactivation (XCI) of the small ring X chromosome, which leads to functional X disomy (FXD), To explore this hypothesis, we examined the proportion of FXD cells in the peripheral blood of four ring X Turner syndrome females with various levels of MR, using two newly developed XCI assays based on DNA methylation of X-linked genes. As a result, the two patients with extremely severe MR showed complete FXD patterns, whereas the remaining two patients with relatively milder MR showed partial FXD patterns. These results indicate that the proportion of FXD cells may be associated with the severity of MR in mosaic ring X Turner syndrome females, although this association should be confirmed by examining brain cells during development. One of the cases with severe MR and a complete FXD pattern neither lacked the XIST gene nor had uniparental X isodisomy, and we discuss the mechanism of the failure of XCI in this case.

A novel control process of cyanobacterial bloom using cyanobacteriolytic bacteria immobilized in floating biodegradable plastic carriers

A process using a floating carrier for immobilization of cyanobacteriolytic bacteria, B.cereus N-14, was proposed to realize an effective in situ control of natural floating cyanobacterial blooms. The critical concentrations of the cyanobacteriolytic substance and B.cereus N-14 cells required to exhibit cyanobacteriolytic activity were investigated. The results indicated the necessity of cell growth to produce sufficiently high amounts of the cyanobacteriolytic substance to exhibit its activity and also for conditions enabling good contact between high concentrations of the cyanobacteriolytic substance and cyanobacteria. Floating biodegradable plastics made of starch were applied as a carrier material to maintain close contact between the immobilized cyanobacteriolytic bacteria and floating cyanobacteria. The floating starch-carriers could eliminate 99% of floating cyanobacteria in 4 d. Since B.cereus N-14 could produce the cyanobacteriolytic substance under the presence of starch and some amino acids, the cyanobacteriolytic activity could be attributed to carbon source fed from starch carrier and amino acids eluted from lysed cyanobacteria. Therefore, the effect of using a floating starch-carrier was confirmed from both view points as a carrier for immobilization and a nutrient source to stimulate cyanobacteriolytic activity. The new concept to apply a floating carrier immobilizing useful microorganisms for intensive treatment of a nuisance floating target was demonstrated.

Biodegradation of microcystis and microcystins by indigenous nanoflagellates on biofilm in a practical treatment facility

The potential for degradation of Microcystis and microcystins by organisms in biofilm in a practical biological treatment facility combined with conventional treatment processes was examined. Viable cells of Microcystis viridis, which produced microcystin LR, RR and YR, were degraded in 6 to 10 days by the addition of biofilm collected in early summer, mid-summer and autumn. Monas sp. grew remarkably well compared with other organisms in the samples of all seasons. Therefore, we conclude that Monas sp. was indigenous animals in the biological treatment facility and was able to degrade Microcystis cells. Some previous studies reported the predation of Microcystis cells by Monas guttula in pure culture conditions (monoxenic culture). We clarified that Monas sp. can grow and prey on Microcystis cells even in mixed culture including many kinds of other organisms in biofilm in a practical treatment facility. Also, intracellular microcystin LR, RR and YR in Microcystis cells could be degraded simultaneously with high reduction of Microcystis cells by organisms in biofilm.

Comparison of detection specificity of nitrifying bacteria in biofilm using fluorescence in situ hybridization and in situ fluorescent antibody methods

The in situ fluorescent antibody and fluorescence in situ hybridization (FISH) methods are very useful in the in situ detection of specific bacteria like nitrifiers in a biofilm. In this study, simultaneous staining using the FISH and in situ fluorescent antibody methods was examined. As a result, no specific fluorescence was observed with either method when FISH was performed followed by the in situ fluorescent antibody method; however, when the in situ fluorescent antibody method was performed first followed by FISH, specific fluorescence was observed in both cases. Moreover, it was suggested that the detection specificities of FISH and the in situ fluorescent antibody method are almost identical.

Experimental parkinsonism in primates

Early in the 1960s the primate model of Parkinson's disease was first introduced by placing an electrolytic lesion in the midbrain. In the 1980s, a dopaminergic neurotoxin, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was accidentally shown to induce parkinsonism in humans, and subsequently was confirmed to reproduce an almost perfect model of parkinsonism in primates. In the late 1980s chemical manipulations of the basal ganglia were shown to induce parkinson symptoms, especially dyskinesia, and more recently, chemical lesioning of the pedunculopontine tegmental nucleus has also been shown to induce parkinsonism. We still do not have a perfect animal model of parkinsonism, however, these models have offered excellent opportunities to study the basic mechanisms in parkinsonism and the function of the basal ganglia.

The role of the pedunculopontine tegmental nucleus in experimental parkinsonism in primates

To clarify the role of the pedunculopontine tegmental nucleus (PPN) in motor behavior, we have conducted a series of experiments in primates. In the first part, PPN was damaged locally with kainic acid, which resulted in mild hemiparkinsonism in the contralateral limbs. In the second part, muscimol (a GABA agonist) was locally injected into the PPN area in monkeys who had been trained to perform a lever-pull movement with an arm, resulting in a slowness of movement and a delay of the movement onset. In the third part, a dopaminergic neurotoxin, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was systemically injected in monkeys with prior PPN lesioning. These monkeys developed no, or if any, very mild parkinsonism. PPN lesioning was supposed to have protected the nigral neurons from the MPTP- toxicity. The PPN facilitates the motor system through its nigral projection. The decreased activity of the PPN may underlie the pathophysiology of parkinsonism.

Screening and characterization of facultative psychrophilic denitrifiers for treatment of nitrate contaminated groundwater using starch-based biodegradable carriers

Potential starch degrading denitrifying microorganisms that can grow at 4 degrees C were isolated from lake sediments to remove nitrate from groundwater. Initial screening using soluble starch as the sole carbon source confirmed that two out of twenty-five isolates (strain no. 2 and 47) significantly reduced nitrate in the medium and liberated nitrogen gas during culture. In a second screening, several commercially available starch based materials and different kinds of starch were tested. Strain 47 was found to have the best denitrification performance compared with strain 2. Using starch based carrier C (a commercial packing material) as carbon source, strain 47 could completely reduce the nitrate nitrogen in the medium after one week of batch culture even at 10 degrees C. Strain 47 could remove nitrate even without trace element supplementation, and it could perform optimally at 1X (10ml l(-1) of trace element solution) level of trace element supplement. The best temperature for denitrification for strain 47 was 15 degrees C and 20 degrees C, but it could also remove nitrate nitrogen at 10 degrees C and 30 degrees C, although at a slower rate. Reactor studies in a simulated treatment well (a cylindrical reciprocating basket reactor) in a repeated fed batch mode showed a good stable denitrification performance as long as substrate limitation is avoided by adequate supply of starch based carrier. Although the similarity score obtained was not enough for phylogenic identification, the results of 16SrRNA sequences analysis for the strain 47 showed a dose relation to Janthinobacterium lividum or Pseudomonas (Janth) mephitica (95.77%).

Microbial community structures of activated sludges dominated with polyphosphate-accumulating bacteria and glycogen-accumulating bacteria

The microbial community structures of anaerobic-aerobic activated sludges, which are dominated with polyphosphate-accumulating bacteria (PABs) and glycogen-accumulating bacteria (GABs), were investigated by quinone profile method and dual staining DAPI (4',6-diamidino-2-phenylindol dihydrochloride) with fluorescent in situ hybridization (FISH). For both activated sludges, the predominant bacterial groups were the beta subclass of the Proteobacteria that contained mainly Q-8 as analyzed by the quinone profile method and gram-positive bacteria with a high DNA G+C content based on FISH. A 16S rRNA-targeted oligonucleotide probe (MP2) specific for M. phosphovorus, a known polyphosphate-accumulating bacterium, was also applied to PABs and GABs-enriched activated sludge to evaluate their possible role in the enhanced biological phosphorus removal (EBPR) process. Interestingly, the bacteria that hybridized with the probe specific to M. phosphovorus in the sludge dominated with PABs represent about 6.9% of the total microorganisms. In the sludge dominated with GABs, these bacteria were about 1.9%. These results suggest its possible involvement in the EBPR process.

Attenuation of glucan-binding protein C reduces the cariogenicity of Streptococcus mutans: analysis of strains isolated from human blood

A blood isolate of Streptococcus mutans strain TW871 shows relatively low homology with MT8148, a reference oral isolate strain, and lacks the serotype-specific polysaccharide antigen, suggesting that other cell-surface structures correlate with cariogenicity. We compared cariogenicity of TW871 with MT8148 (serotype c) and blood isolate TW964 (serotype f) in rats. Strain TW871 showed significantly lower cariogenicity than MT8148 or TW964 and expressed significantly lower sucrose-independent cellular adhesion to saliva-coated hydroxyapatite and dextran-binding activity than strain MT8148. Strains TW871 and TW964 showed a defect in the gbpA gene by Southern hybridization analysis, while sequencing analysis revealed gbpC variation in TW871. These results suggest that variation in GbpC may alter cellular adherence properties and can be correlated with the cariogenicity of S. mutans in this strain.

Perceptual changes in illusory wrist flexion angles resulting from motor imagery of the same wrist movements

Recent neuroimaging studies have suggested that similar cortical motor areas are recruited both by kinesthetic sensations elicited by tendon vibration and by voluntarily imaging one's own movements of the same joints. Little is known, however, as to whether kinesthetic motor imagery interacts with kinesthetic illusion. We examined such interaction by behavioral analysis in which 19 subjects imagined wrist flexion or extension, with or without illusory flexion induced by tendon vibration. Electromyograms were also recorded to monitor the peripheral modulations caused by the interaction. The kinesthetic motor imagery had a psychophysical effect on kinesthetic illusion in the absence of overt movement. It was confirmed that the subjects could imagine wrist movements without facilitating muscle activities in the absence of vibration stimuli. The electromyogram activity of the vibrated extensor muscles was significantly higher than that of non-vibrated flexor muscles. Motor imagery of wrist extension, when illusory flexion was experienced, reduced the angle of illusory flexion while enhancing extensor muscle activities in comparison with the control. On the other hand, flexion motor imagery increased the angle of illusory flexion with or without enhancement of flexor muscle activities. Our results indicate that motor imagery interacts with kinesthetic illusion with or without enhancement of activities of the related muscles. This suggests (1) that common neural substrates shared by imagery and by illusion exist and (2) that different physiological mechanisms contribute to the enhancement of muscle activities of vibrated muscles and their antagonists.

Cardiac rhythms in developing emu hatchlings

Six emu hatchlings were non-invasively measured for electrocardiogram (ECG) from their chest wall using flexible electrodes, and the instantaneous heart rate (IHR) was determined from ECG throughout the first week of post-hatching life. Although the baseline heart rate (HR) was low, approximately 100-200 beats per min (bpm), compared with chick hatchlings, the IHR fluctuated markedly. The fluctuation of IHR comprised HR variability and irregularities that were designated as types I, II and III in chick hatchlings and additional large accelerations distinctive of emu hatchlings. Type I was HR oscillation with a mean frequency of 0.37 Hz (range 0.2-0.7 Hz), i.e. respiratory sinus arrhythmia (RSA). From RSA, breathing frequency in emu hatchlings was estimated to be approximately half of that in chickens. Type II HR oscillation was also found in the emu; the frequency ranged from approximately 0.04 to 0.1 with a mean of 0.06 Hz, and the magnitude tended to be large compared with that of chickens. In addition to type III HRI, which was designated in chickens, large, irregular HR accelerations were characteristic of emu hatchlings. From IHR data, developmental patterns of mean heart rate (MHR) were constructed and plotted on a single graph to inspect the diurnal rhythm of MHR by visual inspection and power spectrum analysis. A circadian rhythm was not clear in the emu hatchlings, in contrast to chick hatchlings, which showed a dominant diurnal rhythm.

Community analysis of nitrifying bacteria in an advanced and compact Gappei-Johkasou by FISH and PCR-DGGE

Fluorescent in situ hybridization (FISH) method with 16S rRNA-targeted oligonucleotide probes was used for quantitative estimation of ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) in a Johkasou. Although the occupation ratios of AOB and NOB increased as nitrification progressed, about one month later, the occupation ratios decreased, despite showing good nitrification ability. Furthermore, even when urea was added to the feeding wastewater to raise the amount of T-N, the occupation ratios of both nitrifying bacteria remained constant. For further investigation, denaturing gradient gel electrophoresis (DGGE) was used to study the community structure of AOB in the Johkasou. As a result, DGGE band patterns and following sequence analysis revealed that the community structure of AOB was complicated and changed during this experiment. It was suggested that even if the occupation ratio of AOB to eubacteria was constant, the majorities of AOB were changed through temperature and load fluctuation. The combination of FISH and PCR-DGGE provides new information that was not available by conventional cultivation-based methods.

Characterization of an algae-lytic substance secreted by Bacillus cereus, an indigenous bacterial isolate from Lake Kasumigaura

In order to develop a practical biological strategy for water bloom-control in Lake Kasumigaura, indigenous algae-lytic bacteria targeting Microcystis spp. (the dominant cyanobacteria), was first carried out. Some basic lytic characteristics of the isolates concerning the biological and physico-chemical factors in actual water environments were then investigated. Fifteen algae-lytic bacteria were successfully isolated using the double layer method. The isolate showing the highest lytic activity was identified as Bacillus cereus based on the 16SrRNA sequence. Extracellular products of B. cereus were found to be responsible for algae-lytic activity. Algae-lytic assay tests using bacterial supernatants pre-treated under several conditions indicated that the majority of the effective algae-lytic substances were either hydrophilis or hydrophobics with a carbon number less than 18, and with molecular weight less than 2000 Da. The algae-lytic activity of the bacterial supernatant was found to be enhanced under alkaline conditions, but it was lost under acidic conditions. This pH specific characteristic is advantageous for application in water bloom environments where the pH is usually in the alkaline region.

Degradation of microcystin by biofilm in practical treatment facility

Potential for degradation of microcystin by biofilm was examined by some batch experiments using biofilm scraped from practical biological treatment facility combined with conventional treatment processes. The viable cells of Microcystis viridis, which produced microcystin LR, RR and YR were degraded at 6 to 10 days by the addition of biofilm. Biofilm collected in summer season had especially higher potential for degradation of Microcystis with complete degradation at 6 days. In all seasons, Monas spp. grew remarkably, accompanied with the higher decrease of the viable cells of Microcystis and the micro-animals were considered as a main predator for Microcystis cells. Intracellular microcystin LR, RR, YR were degraded simultaneously with high reduction of Microcystis cells. Dissolved microcystin LR of 1,000 microg l(-1) was effectively degraded by indigenous aquatic bacteria on biofilm during 5 days, the degradability became higher with the increase in the concentration of microcystin LR. From the results of our research, it was clarified that the aggregated microorganisms consisting of biofilm had high potential for degradation of intracellular and dissolved microcystin.

Detection and quantification of expression of amoA by competitive reverse transcription-pCR

Ammonia oxidation by chemolithoautotrophic ammonia-oxidizing bacteria is an important step in the biological nitrogen removal process. The first conversion step, the oxidation of ammonia to hydroxylamine is catalyzed by ammonia monooxygenase (AMO). To investigate the activity of ammonia oxidation, mRNA (designated as amoA) encoding a subunit of AMO was quantified by competitive reverse transcription (RT)-PCR. As a result, it was possible to detect and quantify amoA expression in cultured Nitrosomonas europaea and even complex microbial communities such as nitrifying bacterial aggregates by competitive RT-PCR. It was estimated that amoA concentration in cultured N. europaea was 2.3 x 10(8) copies x ml(-1). Additionally, it was calculated that the copy number of amoA in nitrifying bacterial aggregates was 1.0 x 10(12) copies x ml(-1) (5.1 x 10(10) copies x mg(-1)-dry weight). On the other hand, amoA expression in the natural activated sludge in a household Gappei-Johkaso was undetectable, whereas 16S rRNA of ammonia-oxidizing bacteria was detected by RT-PCR. Then, four days cultivation of this sludge in inorganic artificial wastewater resulted in increasing amoA expression to a quantifiable amount by competitive RT-PCR. In conclusion, the competitive RT-PCR was effective to investigate the expression of amoA as an indicator of ammonia oxidation activity by autotrophic ammonia-oxidizing bacteria.

A novel strategy for cyanobacterial bloom control by ultrasonic irradiation

The application of ultrasonic irradiation to control cyanobacterial blooms was evaluated in actual eutrophic lake water. Ten prototype units of the Ultrasonic Irradiation System (USIS) were installed in the 32 ha Lake Senba, and the water and sediment quality were monitored for 2 years. By incorporating the ultrasonication process with the on-going strategy, particularly flushing with induction water, cyanobacterial blooms can be controlled effectively. In addition, a significant improvement in the conditions of the lake in terms of chlorophyll-a, COD and T-P was attained. Moreover, the feasibility of ultrasonic irradiation and bacterial assisted control of cyanobacterial blooms was also evaluated in laboratory conditions. The destruction of gas vacuoles brought about by ultrasonic irradiation promoted close contact between cyanobacteria and their lysing Myxobacter leading to immediate and accelerated destruction of the cells.

Characterization of hK4 (prostase), a prostate-specific serine protease: activation of the precursor of prostate specific antigen (pro-PSA) and single-chain urokinase-type plasminogen activator and degradation of prostatic acid phosphatase

hK4 (prostase, KLK4), a recently cloned prostate-specific serine protease and a member of the tissue kallikrein family, is a zymogen composed of 228 amino acid residues including an amino-terminal propiece, Ser-Cys-Ser-Gln-. A chimeric form of hK4 (ch-hK4) was constructed in which the propiece of hK4 was replaced by that of prostate-specific antigen (PSA) to create an activation site susceptible to trypsin-type proteases. ch-hK4 was expressed in Escherichia coli, isolated from inclusion bodies, refolded, and purified with an overall yield of 25%. The zymogen was readily self-activated during the refolding process to generate an active form (21 kDa) of hK4 (rhK4). rhK4 cleaved the chromogenic substrates Val-Leu-Arg-pNA (S-2266), Pro-Phe-Arg-pNA (S-2302), Ile-Glu-Gly-Arg-pNA (S-2222), and Val-Leu-Lys-pNA (S-2251), indicating that rhK4 has a trypsin-type substrate specificity. The rhK4 was inhibited by aprotinin (6 kDa), forming an equimolar 27 kDa complex. rhK4 readily activated both the precursor of PSA (pro-PSA) and single chain urokinase-type plasminogen activator (scuPA, pro-uPA). rhK4 also completely degraded prostatic acid phosphatase but failed to cleave serum albumin, another protein purified from human seminal plasma. These results indicate that hK4 may have a role in the physiologic processing of seminal plasma proteins such as pro-PSA, as well as in the pathogenesis of prostate cancer through its activation of pro-uPA.

In situ algal bloom control by the integration of ultrasonic radiation and jet circulation to flushing

A novel strategy for in situ water bloom control was applied and evaluated in Lake Senba. The proposed strategy was to integrate ultrasonic radiation and water jet circulation to an existing flushing process for reducing the growth rate of cyanobacteria and to support the flushing process by providing efficient mixing. Ten units of the system, each consisting of an ultrasonication module and a water jet circulator module, were strategically situated on the lake, and the performance was monitored for 2 years. Water bloom occurrence reflected as chlorophyll a, SS, and transparency were controlled to lower levels when the integrated system was coupled with sufficient inflow water supply to achieve the target flushing rate. Also, an improvement in the water quality such as COD and phosphorus were observed. Based on linear regression analysis, relationships between water quality parameters and inflow water volume were discussed to evaluate the proposed strategy. Of the three major water quality parameters associated with water bloom, the integrated system contributed mainly to the reduction in SS and transparency compared to chlorophyll a reduction. Improved chlorophyll a reduction may be achieved by strategies that augment effective washout of cyanobacteria during flushing.

Application of 4-hydroxyantipyrine and acetaminophen O-sulfate as biodistribution promoter

The effects of 4-hydroxyantipyrine (4-OH), a major metabolite of antipyrine and its sulfate, 4-hydroxyantipyrine O-sulfate (4-S), on the pharmacokinetics of citicoline and thiopental sodium were investigated in rats. The concomitant use of 4-OH increased significantly the tissue-to-plasma concentration ratio (Kp) of citicoline in the brain and liver and that of thiopental sodium in the brain, liver, and heart, while 4-S did not affect them. The permeability clearance of blood-brain barrier (BBB) (Kin) and the total distribution volume (Vdbr) of citicoline were not affected by either 4-OH or 4-S. However, those of thiopental sodium were significantly increased by not only 4-OH but also by 4-S. On the other hand, the plasma concentration of antipyrine was significantly decreased by the intravenous bolus coadministration of N-acetyl-p-aminophenyl O-sulfate (APAPS) at steady-state plasma concentration of antipyrine. A similar reduction was not observed with the intravenous coadministration of acetaminophen (APAP). The Kp value of antipyrine was significantly increased in the brain by the coadministration of APAPS, but was not affected by APAP. The increment in the drug distribution to the brain with the concomitant use of 4-OH (or APAPS) observed in this study is useful information for the application of drug combinations as biodistribution promoters.

Prevalence of Helicobacter pylori infection and correlation between severity of upper gastrointestinal lesions and H. pylori infection in Japanese patients with Crohn's disease

BACKGROUND

The prevalence of Helicobacter pylori infection in Crohn's disease (CD) patients was investigated to determine whether the presence and severity of gastroduodenal lesions were related to H. pylori infection.

METHODS

Infection rates were compared between CD group (n = 90) and the control group (n = 525). Correlations between endoscopically detected lesions and H. pylori positive rates were investigated. The relationship between drug therapy and the prevalence of H. pylori infection was also analyzed.

RESULTS

H. pylori-positive rate of the 90 CD patients attending our clinic was 16.7%, significantly lower than the rate in healthy controls (40.2%) (P = 0.0001). The involvement of H. pylori infection in the gastroduodenal lesions of CD patients was also examined. The prevalence of gastroduodenal lesions in all CD patients was high, 92.2%. The lesions observed included ulcers, erosion, and "bamboo joint-like lesions" of the stomach, and ulcers, erosion, stenosis, and elevated lesions of the duodenum. None of these lesions were found to be related to H. pylori infection. However, H. pylori infection was found to exacerbate gastric ulcers (P = 0.036). The analysis of a possible relationship between a history of drug therapy and the low prevalence of H. pylori infection in CD patients showed that the prevalence of H. pylori infection was significantly lower in patients who had received antibiotics for 2 weeks or more (P = 0.002).

CONCLUSIONS

The results suggest that H. pylori infection is essentially unrelated to the gastroduodenal lesions observed in CD. It seems likely, however, that H. pylori infection may exacerbate gastric ulcers and that H. pylori can be eradicated by prolonged use of antibiotics.

Transactivation via RAR/RXR-Sp1 interaction: characterization of binding between Sp1 and GC box motif

Modulation of Sp1 activity by nuclear receptors is a novel mechanism by which fat-soluble hormones regulate gene expression. We previously established that upon autoinduction of RARs by RA, RARs/RXRs physically interact with Sp1, potentiate Sp1 binding to the GC box motifs, and thus enhance transactivation of the urokinase promoter, which lacks a canonical RAR-responsive element/RXR-responsive element. Here, we examined whether a similar mechanism might participate in transcriptional regulation of other key RA-inducible genes in endothelial cells and characterized binding between Sp1 and GC box motifs. Northern blot analyses showed that in addition to urokinase, after induction of RARs, RA up-regulates GC-rich region-dependent mRNA expression of transglutaminase, TGF beta 1, and types I and II TGF beta receptors. RA failed to alter the expression of Sp1 at both mRNA and protein levels. Reporter and gel shift assays and Western blot analyses suggested that either RA-treatment or RAR/RXR-overexpression enhances transactivation of these genes through a GC-rich region and strengthens the affinity of Sp1 to GC box motifs, accompanying a potential conformational change of Sp1 as reflected in its increased immunogenicity. Detailed analyses of the GC box motifs within the urokinase and other promoters indicate that interaction between RAR/RXR and Sp1 does not occur in the presence of nonfunctional GC box motifs containing five tandem purine or pyrimidine bases at the 3'-flanking region of hexanucleotide core sequence. These findings provide insight into the molecular mechanisms underlying RARE/RXRE-independent transactivation of RA-inducible gene promoters.

Pulmonary venous obstruction requiring lobectomy for hemoptysis after a Glenn operation

Right atrial isomerism is well known to be associated with anomalous pulmonary venous drainage and a potentially dangerous sequel to pulmonary venous obstruction, and is associated with high mortality. We report a 16-month-old girl with pulmonary venous obstruction requiring lobectomy for hemoptysis after a Glenn operation. Two years after surgery, she is doing well with 80% oxygen saturation and no further episodes of hemoptysis.

Expression of cytokines and transcription factors in photocoagulated human retinal pigment epithelial cells

BACKGROUND

It has been shown that scatter photocoagulation induces regression of retinal neovascularization, but the mechanism for this effect is not completely understood. The main focus of our research is to determine the mechanism for the beneficial effects of photocoagulation. In the present study, we quantified the expression of growth factors and transcription factors that inhibit or induce angiogenesis in photocoagulated human retinal pigment epithelial (RPE) cells in vitro.

METHODS

RPE cells were grown to confluence, and RNA was isolated from the RPE cells with or without photocoagulation. The following growth factors, their receptors and transcription factors were examined by reverse transcription polymerase chain reaction (RT-PCR): transforming growth factor (TGF)-beta 1, basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), kinase insert domain-containing receptor (KDR/flk-1), hypoxia-inducible factor (HIF)-1, ETS-1, nuclear factor kappa B (NF-kappa B), interleukin-8 (IL-8).

RESULTS

Laser photocoagulation increased the expression of TGF-beta 1. Expression of angiogenic factors bFGF, VEGF, IL-8 and their transcription factor, ETS1, was also increased. However, the up-regulation of these factors was observed early (6 h) after photocoagulation. Seventy-two hours after photocoagulation, when RPE cells were repaired, the expression of VEGF, IL-8, ETS-1, and NF-kappa B was decreased to the levels before photocoagulation.

CONCLUSIONS

These results suggest that TGF-beta produced by photocoagulated RPE cells and the down-regulation of angiogenic factors in repaired RPE cells, in all likelihood, play an important role in the processes that occur after laser photocoagulation.

Upregulation of pigment epithelium-derived factor after laser photocoagulation

PURPOSE

To determine the changes in the expression of pigment epithelium-derived factor in cultured human retinal pigment epithelial cells and rat retinas after laser photocoagulation.

METHODS

Experimental study of laser photocoagulation on human retinal pigment epithelial cells in culture and on adult rats. Reverse transcription-polymerase chain reaction and semiquantitative polymerase chain reaction analysis were used.

RESULTS

After photocoagulation, the mRNA expression of pigment epithelium-derived factor was upregulated in human retinal pigment epithelial cells at 6 hours and then gradually decreased. Compared with controls, significantly higher levels of pigment epithelium-derived factor were observed in rat retinas from 6 to 24 hours after laser photocoagulation (P <.005), and they were still higher than before photocoagulation at 2 weeks.

CONCLUSION

An upregulation of pigment epithelium-derived factor in retinal pigment epithelial cells and in the retina after photocoagulation suggests that pigment epithelium-derived factor plays a role in inhibiting neovascularization by its antiangiogenic activity.