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.

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.