Injection of a recombinant AAV serotype 2 into canine skeletal muscles evokes strong immune responses against transgene products

Using murine models, we have previously demonstrated that recombinant adeno-associated virus (rAAV)-mediated microdystrophin gene transfer is a promising approach to treatment of Duchenne muscular dystrophy (DMD). To examine further therapeutic effects and the safety issue of rAAV-mediated microdystrophin gene transfer using larger animal models, such as dystrophic dog models, we first investigated transduction efficiency of rAAV in wild-type canine muscle cells, and found that rAAV2 encoding beta-galactosidase effectively transduces canine primary myotubes in vitro. Subsequent rAAV2 transfer into skeletal muscles of normal dogs, however, resulted in low and transient expression of beta-galactosidase together with intense cellular infiltrations in vivo, where cellular and humoral immune responses were remarkably activated. In contrast, rAAV2 expressing no transgene elicited no cellular infiltrations. Co-administration of immunosuppressants, cyclosporine and mycophenolate mofetil could partially improve rAAV2 transduction. Collectively, these results suggest that immune responses against the transgene product caused cellular infiltration and eliminated transduced myofibers in dogs. Furthermore, in vitro interferon-gamma release assay showed that canine splenocytes respond to immunogens or mitogens more susceptibly than murine ones. Our results emphasize the importance to scrutinize the immune responses to AAV vectors in larger animal models before applying rAAV-mediated gene therapy to DMD patients.

Upregulation of the brain renin-angiotensin system in rats with chronic renal failure

AIM

We investigated how the brain renin-angiotensin system is involved in regulation of the sympathetic activity and arterial pressure in rats with chronic renal failure.

METHODS

Systolic arterial pressure, heart rate and diurnal urinary noradrenaline excretion were measured for 12 weeks in spontaneously hypertensive rats (SHR) with or without subtotal nephrectomy. Expression of mRNAs related to the brain renin-angiotensin system was measured using polymerase chain reaction. Effects of a 6-day intracerebroventricular infusion of a type 1 angiotensin II receptor antagonist (candesartan) or bilateral dorsal rhizotomy on these variables were also investigated.

RESULTS

Systolic arterial pressure and urinary excretion of noradrenaline were consistently higher in subtotally nephrectomized SHR than in sham-operated SHR (262 +/- 5 vs. 220 +/- 3 mmHg, P < 0.001; 2.71 +/- 0.22 vs. 1.69 +/-0.19 ng g(-1) body weight day(-1), P < 0.001). Expression of renin, angiotensin-converting enzyme and type 1 angiotensin II receptor mRNAs in the hypothalamus and lower brainstem was greater in subtotally nephrectomized SHR than in sham-operated SHR. Continuous intracerebroventricular infusion of candesartan attenuated hypertension and the increase in urinary noradrenaline excretion in subtotally nephrectomized SHR. Dorsal rhizotomy decreased arterial pressure, urinary excretion of noradrenaline and expression of renin-angiotensin system-related mRNAs in brains of subtotally nephrectomized SHR.

CONCLUSION

The brain renin-angiotensin system in subtotally nephrectomized SHR appears to be activated via afferent nerves from the remnant kidney, resulting in sympathetic overactivity and hypertension in this chronic renal failure model.

High-yield synthesis of conductive carbon nanotube tips for multiprobe scanning tunneling microscope

We have established a fabrication process for conductive carbon nanotube (CNT) tips for multiprobe scanning tunneling microscope (STM) with high yield. This was achieved, first, by attaching a CNT at the apex of a supporting W tip by a dielectrophoresis method, second, by reinforcing the adhesion between the CNT and the W tip by electron beam deposition of hydrocarbon and subsequent heating, and finally by wholly coating it with a thin metal layer by pulsed laser deposition. More than 90% of the CNT tips survived after long-distance transportation in air, indicating the practical durability of the CNT tips. The shape of the CNT tip did not change even after making contact with another metal tip more than 100 times repeatedly, which evidenced its mechanical robustness. We exploited the CNT tips for the electronic transport measurement by a four-terminal method in a multiprobe STM, in which the PtIr-coated CNT portion of the tip exhibited diffusive transport with a low resistivity of 1.8 kOmega/microm. The contact resistance at the junction between the CNT and the supporting W tip was estimated to be less than 0.7 kOmega. We confirmed that the PtIr thin layer remained at the CNT-W junction portion after excess current passed through, although the PtIr layer was peeled off on the CNT to aggregate into particles, which was likely due to electromigration or a thermally activated diffusion process. These results indicate that the CNT tips fabricated by our recipe possess high reliability and reproducibility sufficient for multiprobe STM measurements.

Differential cross section and photon-beam asymmetry for the gamma n --> K+ Sigma- reaction at E gamma = 1.5-2.4 GeV

Differential cross sections and photon-beam asymmetries have been measured for the gamma n --> K+ Sigma- and gamma p --> K+Sigma0 reactions separately using liquid deuterium and hydrogen targets with incident linearly polarized photon beams of E gamma = 1.5-2.4 GeV at 0.6 < cos ThetacmK< 1. The cross section ratio of sigma K+ Sigma-/sigma K+ Sigma0, expected to be 2 on the basis of the isospin 1/2 exchange, is found to be close to 1. For the K+ Sigma- reaction, large positive asymmetries are observed, indicating the dominance of K* exchange. The large difference between the asymmetries for the K+ Sigma- and K+ Sigma0 reactions cannot be explained by simple theoretical considerations based on Regge model calculations.

The hemoglobin receptor protein of porphyromonas gingivalis inhibits receptor activator NF-kappaB ligand-induced osteoclastogenesis from bone marrow macrophages

Extracellular proteinaceous factors of Porphyromonas gingivalis, a periodontal pathogen, that influence receptor activator of nuclear factor-kappaB (NF-kappaB) ligand (RANKL)-induced osteoclastogenesis from bone marrow macrophages were investigated. The culture supernatant of P. gingivalis had the ability to inhibit RANKL-induced in vitro osteoclastogenesis. A major protein of the culture supernatant, hemoglobin receptor protein (HbR), suppressed RANKL-induced osteoclastogenesis in a dose-dependent fashion. HbR markedly inhibited RANKL-induced osteoclastogenesis when present in the culture for the first 24 h after addition of RANKL, whereas no significant inhibition was observed when HbR was added after 24 h or later, implying that HbR might interfere with only the initial stage of RANKL-mediated differentiation. HbR tightly bound to bone marrow macrophages and had the ability to induce phosphorylation of ERK, p38, NF-kappaB, and Akt. RANKL-induced phosphorylation of ERK, p38, and NF-kappaB was not suppressed by HbR, but that of Akt was markedly suppressed. HbR inhibited RANKL-mediated induction of c-Fos and NFATc1. HbR could induce beta interferon (IFN-beta) from bone marrow macrophages, but the induction level of IFN-beta might not be sufficient to suppress RANKL-mediated osteoclastogenesis, implying presence of an IFN-beta-independent pathway in HbR-mediated inhibition of osteoclastogenesis. Since rapid and extensive destruction of the alveolar bone causes tooth loss, resulting in loss of the gingival crevice that is an anatomical niche for periodontal pathogens such as P. gingivalis, the suppressive effect of HbR on osteoclastogenesis may help the microorganism exist long in the niche.

Influence of food platform width of mandibular removable partial denture on food mixing ability

The aim of this study was to clarify the influence of food platform width on food mixing ability in patients with mandibular removable partial dentures (RPDs). Twelve subjects (six males and six females, mean age 56.8 years) with intact dentition except for unilaterally missing mandibular first and second molars participated in the study. The food platforms of their RPDs were made of light polymerized composite and three platform conditions were evaluated. A food platform (Control condition) had 7 mm width with a central focus on the top of the residual ridge. Narrowed platforms (5 mm) were created by trimming a lingual portion (Buccally oriented occlusion, Buccal condition) or a buccal portion (Lingually oriented occlusion, Lingual condition) from the control. Subjects chewed a standardized wax cube which provided an estimate of food mixing ability [Mixing Ability Index (MAI)] for each of the three platforms. A significant effect (P < 0.001) on the MAI was found for food platform type (repeated measures one-way analysis of variance). Tukey multiple comparisons found significant differences of MAI between Control condition (1.05 +/- 0.26) and Buccal condition (0.86 +/- 0.23) (P = 0.032), and between Control and Lingual condition (0.54 +/- 0.37) (P < 0.001). Furthermore, MAI with Lingual condition was significantly smaller than that with Buccal condition (P < 0.001). These results suggest that reduction in the width of the food platform may impair masticatory function and the buccal portion of mandibular food platform of RPD is more critical for food mixing than the lingual portion of the platform.

Homogeneous enzymatic assay for L-cysteine with betaC-S lyase

We have developed a new enzymatic assay for determining L-cysteine concentration. The method involves the use of betaC-S lyase from Streptococcus anginosus, which catalyzes the alpha,beta-elimination of L-cysteine to hydrogen sulfide, pyruvate, and ammonia. The production of pyruvate is measured by D-lactate dehydrogenase and NADH. The decrease in NADH was proportional to the L-cysteine concentration up to 1.0 mM. When serum samples were used, within-day and day-to-day coefficient variations were below 4%. This method is simple, and can easily and reliably be used for accurate determination of L-cysteine concentration in serum or other samples.

Functional dissection of YabA, a negative regulator of DNA replication initiation in Bacillus subtilis

The regulation of initiation of DNA replication is crucial to ensure that the genome is replicated only once per cell cycle. In the Gram-positive bacterium Bacillus subtilis, the function of the YabA protein in initiation control was assigned based on its interaction with the DnaA initiator and the DnaN sliding clamp in the yeast two-hybrid and on the overinitiation phenotype observed in a yabA null strain. However, YabA is unrelated to known regulators of initiation and interacts with several additional proteins that could also be involved directly or not in initiation control. Here, we investigated the specific role of YabA interactions with DnaA and DnaN in initiation control by identifying single amino acid changes in YabA that disrupted solely the interaction with DnaA or DnaN. These disruptive mutations delineated specific interacting surfaces involving a Zn2+-cluster structure in YabA. In B. subtilis, these YabA interaction mutations abolished both initiation control and the formation of YabA foci at the replication factory. Upon coexpression of deficient YabA mutants, mixed oligomers formed foci at the replisome and restored initiation control, indicating that YabA acts within a heterocomplex with DnaA and DnaN. In agreement, purified YabA oligomerized and formed complexes with DnaA and DnaN. These findings underscore the functional association of YabA with the replication machinery, indicating that YabA regulates initiation through coupling with the elongation of replication.

Treatment of vertebro-basilar dissecting aneurysms using intravascular stents

SUMMARY

Endovascular surgery is an established primary therapeutic modality for dissecting aneurysms at vertebro-basilar arteries. Intravascular stents can be used to treat the dissecting aneurysms for which simple obliteration procedures cannot be used. In such cases, stent implantation alone or a combination of stents and coils need to be selected properly by taking into consideration the site and shape of dissections. In this report, three patterns of stent application are described and their method of selection is discussed.

Action of neuropeptide Y on nociceptive transmission in substantia gelatinosa of the adult rat spinal dorsal horn

Effects of neuropeptide Y (NPY) on substantia gelatinosa neurons were investigated in adult rat spinal cord slices using blind whole-cell patch-clamp technique. Bath application of NPY (1 microM) induced a membrane hyperpolarization, resulting in a suppression of the dorsal root stimulation-induced action potentials in 24% of the substantia gelatinosa neurons tested. In voltage clamp mode, NPY produced an outward current dose-dependently in about one third of substantia gelatinosa neurons at the holding potential of -60 mV, which was not affected by tetrodotoxin (1 microM). The NPY-induced current was suppressed by perfusion with a Ba2+-containing external solution and a Cs2SO4 or tetraethylammonium-containing pipette solution. In addition, The NPY-induced outward currents reversed its polarity near the equilibrium potential of K+ ions (-93 mV). The response to NPY recorded with guanosine-5'-O-(2-thiodiphosphate)-beta-S (GDP-beta-S) containing pipette solution was abolished 30 min after patch formation, suggesting that the response was mediated by the G-protein-coupled receptors. Application of an NPY-Y1 selective agonist, [Leu(31), Pro(-34)]-NPY (1 microM), for 30 s also induced an outward current with a similar time course and amplitude to that induced by NPY. On the other hand, the NPY response was blocked by a simultaneous application of NPY-Y1 selective antagonist, BIBP 3226 (1 microM). No significant changes were found in amplitude and frequency of miniature excitatory postsynaptic currents and dorsal root evoked excitatory postsynaptic currents by NPY. In addition, NPY did not affect both of the miniature inhibitory postsynaptic currents and evoked inhibitory postsynaptic currents, mediated by either the GABA or glycine receptor. These findings, taken together, suggest that NPY produces an outward current in substantia gelatinosa neurons through G-protein coupled, and NPY-Y1 receptor-mediated activation of K+ channels without affecting presynaptic components. The inhibition of the synaptic transmission from the primary fibers to the substantia gelatinosa neurons is considered to contribute to the antinociceptive effects of NPY.

Near-threshold diffractive psi-meson photoproduction from the proton

Photoproduction of a phi meson on protons was studied by means of linearly polarized photons at forward angles in the low-energy region from threshold to Egamma = 2.37 GeV. The differential cross sections at t = -|t|min do not increase smoothly as Egamma increases but show a local maximum at around 2.0 GeV. The angular distributions demonstrate that phi mesons are photoproduced predominantly by helicity-conserving processes, and the local maximum is not likely due to unnatural-parity processes.

Novel stationary-phase-upregulated protein of Porphyromonas gingivalis influences production of superoxide dismutase, thiol peroxidase and thioredoxin

Porphyromonas gingivalis, an obligately anaerobic bacterium, is implicated as a major pathogen in the development and progression of chronic periodontitis. Although expression of several virulence factors of the bacterium has been found to be affected by environmental stress such as entrance into the stationary growth phase and heat, there is relatively little information on the mechanisms that may operate in the bacterium in response to environmental stress. In this study, a novel protein (UstA) was investigated that was initially identified following two-dimensional gel analysis. Expression of UstA was upregulated in stationary phase or by exposure to atmospheric oxygen. N-terminal sequencing and database analysis with the P. gingivalis genome sequence revealed that the UstA-encoding gene (ustA) was located upstream of a homologue of the usp gene encoding the universal stress protein on the chromosome. The ustA gene appeared to be transcribed in a monocistronic fashion, as revealed by primer extension and Northern blot analysis. To elucidate the role of UstA in the bacterium, chromosomal mutants carrying a disruption of the ustA gene were constructed. The ustA mutant grew slower than the wild-type parent strain in rich medium, resulting in a lower yield in stationary phase. Furthermore, in this mutant, expression levels of the P. gingivalis homologues of superoxide dismutase, thiol peroxidase and thioredoxin were markedly higher than those in the wild-type, especially in stationary phase. The ustA mutant was more resistant to diamide, a thiol-specific oxidant, than the wild-type. In addition, the ustA mutation suppressed hypersensitivities of the oxyR mutant to diamide, metronidazole and mitomycin C. These results suggest that UstA may play a significant role in oxidative stress responses in the bacterium.

Aortic and vena caval reconstruction with retroperitoneal lymph node dissection for metastatic germ cell tumor

A 49-year-old man who had a huge testicular tumor with retroperitoneal lymph node metastasis and bilateral multiple pulmonary metastases was referred to our hospital. Firstly orchiectomy was done obtaining the pathological diagnosis of mixed type germ cell tumor. After cisplatin-based chemotherapy, he underwent resection of the retroperitoneal lymph node involving the abdominal aorta and the inferior vena cava. Both great vessels were resected with the tumor and reconstructed with prosthetic grafts. Two months after the laparotomy, 12 metastatic nodules in the left lung were resected. Seven months later, he furthermore underwent resection of 4 metastatic nodules in the right lung. Microscopically, all resected metastatic tumors were diagnosed to be mature teratoma without viable malignant cells. The patient remains well 30 months after the first operation. Follow-up CT scan demonstrates patency of aortic and vena caval bypass grafts without local recurrence or distant metastasis.

Functional reorganization of the spinal pain pathways in developmental and pathological conditions

Following inflammation, a subpopulation of Abeta afferents that terminates preferentially in deeper laminae have been shown to extend their axons to the superficial dorsal horn, particularly substantia gelatinosa (SG). Similarly, SG neurons in immature spinal cord receive mainly Abeta afferent inputs. To clarify whether the reorganized sensory pathway in the inflamed rats has a functional similarity with that in the developmental state, we compared synaptic inputs from primary afferents using in vitro and in vivo patch-damp recordings from SG neurons. SG neurons in the mature state had monosynaptic inputs from Adelta and C afferents, while only a few neurons received inputs from Abeta afferents. Following inflammation, the Abeta afferents extended their axons to SG and established functional monosynaptic transmission. Meanwhile, SG neurons in the immature state received preferentially Abeta as well as Adelta afferent inputs, and the majority of Abeta afferent inputs were monosynaptic. These observations support the idea that the sprouting of the large afferent fibres observed in inflamed rats is, at least in part, a regeneration process. However, the process, maybe distinct at some point from the process during development, therefore, produces pathological pain. Though the idea that the regeneration mimics the developmental process has been widely accepted, other possibilities cannot be excluded.

Analysis of receptive fields revealed by in vivo patch-clamp recordings from dorsal horn neurons and in situ intracellular recordings from dorsal root ganglion neurons

It has been thought that spinal dorsal horn neurons receive convergent inputs from not only somatosensory but also visceral pathways. For instance, the referred pain is presumed to be due to the convergence of sensory inputs from cardiac and shoulder receptive fields. However, precise investigation has not been made from dorsal horn neurons yet, because of difficulty in studying the pathways from those regions by means of conventional electrophysiology. The purpose of this study is to clarify the convergent inputs to single dorsal horn neurons from wide receptive fields using an in vivo patch-clamp recording technique from the superficial spinal dorsal horn and an intracellular recording from dorsal root ganglion neurons that keep physiological connections with the peripheral sites. Identified dorsal root ganglion neurons received an input from a quite small area, about 1 x 1 mm in width of the skin. In contrast, substantia gelatinosa neurons in the spinal cord received inputs from an unexpectedly wide area of the skin. Previous extracellular recordings have, however, revealed that substantia gelatinosa neurons have small receptive field. This discrepancy is probably due mainly to an availability of the in vivo patch-clamp method to analyze sub-threshold synaptic responses. In contrast, the extracellular recording technique allows us to analyze predominantly the firing frequency of neurons. Thus, the in vivo patch-clamp recordings from dorsal horn neurons and the intracellular recordings from DRG neurons will be useful for well understanding the sensory processing in the spinal cord.

Prolonged effects of polyriboinosinic:polyribocytidylic acid on spontaneous running wheel activity and brain interferon-alpha mRNA in rats: a model for immunologically induced fatigue

Following 2 weeks acclimation to the running wheel in the home cages, an i.p. injection of a synthetic double-stranded RNA, polyriboinosinic:polyribocytidylic acid (poly I:C, 3 mg/kg), was performed to produce the immunologically induced fatigue in rats. The daily amounts of spontaneous running wheel activity decreased to about 40-60% of the preinjection level until day 9 with normal circadian rhythm, then gradually returned to the baseline level by day 14. Rats given a heat exposure (36 degrees C for 1 h) for the consecutive 3 days showed an increase in activity except for the first day. In the open field test, the total moving distance and the number of rearing of the poly I:C-injected rats decreased on day 1, but they were not different from the saline-injected group on day 7, suggesting that the poly I:C-induced fatigue on day 7 was not due to the peripheral problems such as muscle/joint pain, but involved the CNS. Quantitative analysis of mRNA levels using a real-time capillary reverse transcriptase-polymerase chain reaction (RT-PCR) method revealed that interferon-alpha (IFN-alpha) mRNA contents in the cortex, hippocampus, hypothalamic medial preoptic, paraventricular, and ventromedial nuclei were higher in the poly I:C group than those in the saline and heat-exposed groups on day 7, although the amount of interleukin-1 beta mRNA showed no differences. Serum adrenocorticotropic hormone and catecholamine levels were not significantly different between groups. The present results indicate that the prolonged fatigue induced by poly I:C, which is evaluated by the spontaneous running wheel activity, can be used as an animal model for the immunologically induced fatigue associated with viral infection, and suggest that brain IFN-alpha may play a role in this model.

Beam-polarization asymmetries for the p(gamma-->, K+)Lambda and p(gamma-->, K+)Sigma(0) reactions for E(gamma)=1.5-2.4 GeV

Beam polarization asymmetries for the p(gamma-->,K+)Lambda and p(gamma-->,K+)Sigma(0) reactions are measured for the first time for E(gamma)=1.5-2.4 GeV and 0.6<cos((theta(c.m.)(K+))<1.0 by using linearly polarized photons at the Laser-Electron-Photon facility at SPring-8 (LEPS). The observed asymmetries are positive and gradually increase with rising photon energy. The data are not consistent with theoretical predictions based on tree-level effective-Lagrangian approaches. Including the new results in the development of the models is, therefore, crucial for understanding the reaction mechanism and to test the presence of baryon resonances which are predicted in quark models but are thus far undiscovered.

Biodiversity meets the atmosphere: a global view of forest canopies

The forest canopy is the functional interface between 90% of Earth's terrestrial biomass and the atmosphere. Multidisciplinary research in the canopy has expanded concepts of global species richness, physiological processes, and the provision of ecosystem services. Trees respond in a species-specific manner to elevated carbon dioxide levels, while climate change threatens plant-animal interactions in the canopy and will likely alter the production of biogenic aerosols that affect cloud formation and atmospheric chemistry.

Evidence for a narrow S = +1 baryon resonance in photoproduction from the neutron

The gamman-->K(+)K(-)n reaction on 12C has been studied by measuring both K+ and K- at forward angles. A sharp baryon resonance peak was observed at 1.54+/-0.01 GeV/c(2) with a width smaller than 25 MeV/c(2) and a Gaussian significance of 4.6sigma. The strangeness quantum number (S) of the baryon resonance is +1. It can be interpreted as a molecular meson-baryon resonance or alternatively as an exotic five-quark state (uuddsmacr;) that decays into a K+ and a neutron. The resonance is consistent with the lowest member of an antidecuplet of baryons predicted by the chiral soliton model.

[Report on the ECR2003 (European Congress of Radiology): comparison of apparent diffusion coefficient (ADC) between different MRI scanners]

PURPOSE

To analyze reproducibility of ADC measurements on different MRI scanners.

METHODS AND MATERIALS

Diffusion-weighted imaging (DWI) of a home-made phantom (gelatine of different concentration was enclosed in case of circle pillar shape) was performed with the following protocol; spin-echo type echo planar imaging; TR=7000 msec, TE=minimal, matrix=128 x 128, FOV=220 mm, slice thickness=5mm, NEX=1, b-factor=0, 500, and 1000 sec/mm(2) on four different 1.5T MR scanners [GE Signa Horizon (two of them), GE Signa Horizon Lx, and Siemens Magnetom Symphony]. Image analysis were performed on a workstation (GE Medical Systems) or on an operators console of Symphony (for data of Symphony). We used two-point method. Regions of interest (ROIs) were set on every part of ADC map of home-made phantom and ADCs were measured. A linear approximation graphs were also made with every MRI scanner and b-factor.

RESULTS

A linear approximation was performed, formulas were y=-0.08x+2.32, r(2)=0.84(Lx), y=-0.09x+2.58, r(2)=0.89(Horizon-1) y=-0.11x+2.67, r(2)=0.95(Horizon-2), y=-0.08x+2.42, r(2)=0.97(Symphony) at b-factor of 500sec/mm(2). y=-0.08x+2.33, r(2)=0.91(Lx), y=-0.09x+2.43, r(2)=0.93(Horizon-1), y=-0.08x +2.48, r(2)=0.92(Horizon-2), y=-0.07x+2.39, r(2)=0.96(Symphony) at b-factor of 1000 sec/mm(2).

CONCLUSIONS

ADC values measured at two MRI scanners (same model and older than the other scanners) are higher than other scanners on b-factor=500 sec/mm(2), but at b-factor=1000 sec/mm(2), a good relationship between every scanners was obtained. This result seems to depend on generation of the MRI scanners; newly scanners have good relations b-factor 500 and 1000 sec/mm(2). Pulse sequence design may be improved and optimized in newly scanners. When ADCs were used as quantitative value, a proper b-factor must be used.

Factors influencing autonomic nervous function during cold-water immersion test in patients with hand-arm vibration syndrome

OBJECTIVES

Factors influencing autonomic nervous function in patients with hand-arm vibration syndrome (HAVS) in response to cold-water immersion test with different water temperatures and immersion times were investigated in the summer and winter seasons.

METHODS

Fourteen HAVS patients with vibration-induced white finger (VWF) and 14 healthy control subjects individually age-matched to the patients consented in writing and participated in this study. Patients and controls immersed their left hands in water at 10 degrees C for 10 min and at 15 degrees C for 3 min in summer and in winter in a room with temperature maintained at 21+/-1 degrees C. Electrocardiographic (ECG) data were recorded during the test period and the R-R intervals were analyzed with a fast Fourier transformation (FFT) program. Percentage of very low frequency (VLF%; indicator of both sympathetic and parasympathetic nervous function, and function of rennin-angiotensin system), low frequency (LF%; indicator of both sympathetic and parasympathetic nervous function), high frequency (HF%; indicator of parasympathetic nervous function), and LF/HF ratio (indicator of sympathetic nervous function) were calculated. The results by three-way analysis of variance (ANOVA) were reported elsewhere. In the present study, repeated measures ANOVA was used to re-analyze the factors of data measurement time (time factor) and group (group factor), and their interaction for each test method (water at 10 degrees C for 10-min immersion time; water at 15 degrees C for 3-min immersion time) in summer and winter.

RESULTS

The HF% of HAVS patients tended to be lower than that of healthy controls throughout the cold-water immersion tests except for during tests involving water at 10 degrees C for 10-min immersion in summer. The group factor for HF% was statistically significant with an exception during the test involving water at 10 degrees C and 10-min immersion time in summer. The time factor for HF% was statistically significant with an exception during the test involving water at 15 degrees C and 3-min immersion time in winter.

CONCLUSIONS

The findings of the present study indicated lower cardiac parasympathetic activity in HAVS patients than in healthy controls, especially in winter. The response of the autonomic nervous system to cold stimulation was to some extent more clearly observed during the immersion test with water at 10 degrees C and 10-min immersion time than during the immersion test with water at 15 degrees C and 3-min immersion time. The results revealed by three-way analysis in a previous study were similar to those in the present study with data analysis by repeated measures ANOVA.

Efficient 355-nm generation in CsB3O5 crystal

We demonstrate UV generation in CSB3O5 (CBO) crystals grown by the top-seeded solution growth technique. 355-nm UV light was generated by use of a type II CBO crystal as a sum frequency of the fundamental light and the second harmonic of a nanosecond Nd:YVO4 laser. A 3.0-W output of the third-harmonic was obtained at a repetition rate of 31 kHz. The conversion efficiency from the fundamental light to the third harmonic reached 30%, which was 1.5 times higher than that obtained with a type II LiB3O5 crystal under the same experimental conditions.

Spallation ultracold-neutron production in superfluid helium

The first ultracold-neutron (UCN) production in superfluid helium placed in a spallation neutron source is carried out. A UCN density of 0.7 UCN/cm(3), which can be used in experiments, is achieved for a proton-beam power of 78 W and a He-II temperature of 1.2 K. The present new UCN source is not limited by Liouville's theorem and extraction losses, which were serious problems in the previous sources. The present source has the possibility of extremely high-density UCN production compared with previous UCN sources.

A Japanese SPG4 family with a novel missense mutation of the SPG4 gene: intrafamilial variability in age at onset and clinical severity

OBJECTIVES

We report the results of clinical and genetic studies on a Japanese SPG4 family.

MATERIAL AND METHODS

Family N included eight patients in four generations with autosomal dominant transmission. We performed neurological and molecular analyses on the SPG4 gene in the family members comprising three patients, 12 at-risk individuals, and three normal spouses.

RESULTS

The three patients showed pure spastic paraplegia, two of them exhibiting a decrease in vibration sense. There was marked intrafamilial variability in age at onset and clinical severity in the present family. On molecular analysis, a novel missense mutation (nt1579 C-->T) in exon 12 of the SPG4 gene was found in the three patients, three probably affected, and an asymptomatic carrier.

CONCLUSION

The present SPG4 family, which was shown to have a novel SPG4 mutation, exhibited marked variability in the clinical features, indicating the participation of additional factors in the phenotypic appearance of this family.

lcd from Streptococcus anginosus encodes a C-S lyase with alpha,beta-elimination activity that degrades L-cysteine

Hydrogen sulfide is highly toxic to mammalian cells. It has also been postulated that hydrogen sulfide modifies haemoglobin resulting in haemolysis. The enzyme that produces hydrogen sulfide from L-cysteine was purified from Streptococcus anginosus. Using the N-terminal amino acid sequence of the purified enzyme, the lcd gene encoding L-cysteine desulfhydrase was cloned; the recombinant protein was then purified to examine its enzymic and biological characteristics. This L-cysteine desulfhydrase had the Michaelis-Menten kinetics K(m)=0.62 mM and V(max)=163 micro mol min(-1) mg(-1). DL-Cystathionine, L-cystine, S-(2-aminoethyl)-L-cysteine, 3-chloro-DL-alanine and S-methyl-L-cysteine were substrates for the enzyme, whereas D-cysteine, DL-homocysteine, L-methionine, DL-serine, DL-alanine, L-cysteine methyl ester, L-tryptophan, L-tyrosine and L-phenylalanine were not. These findings suggest that this L-cysteine desulfhydrase is a C-S lyase that catalyses the alpha,beta-elimination (alphaC-N and betaC-S) reaction. In addition, it is demonstrated that the hydrogen sulfide produced by this enzyme caused the modification and release of haemoglobin in sheep erythrocytes.

Cloning and characterization of the L-cysteine desulfhydrase gene of Fusobacterium nucleatum

Hydrogen sulfide and methyl mercaptan are the two major compounds associated with oral malodor. These compounds are highly toxic, and are thought to play an important role in periodontal disease. Fusobacterium nucleatum, an oral bacterium, produces large amounts of hydrogen sulfide from L-cysteine by the enzymatic action of L-cysteine desulfhydrase. We cloned and sequenced the cdl gene encoding L-cysteine desulfhydrase from F. nucleatum ATCC 10953, and revealed that the structural cdl gene consists of 921 bp and encodes a 33.4-kDa protein. The cloned gene was inserted into an expression vector, pDEST17, and expressed in Escherichia coli as a fused protein. The purified enzyme was tested for substrate specificity using various SH-containing compounds. Only L-cysteine served as a substrate for L-cysteine desulfhydrase to produce hydrogen sulfide.

3-Chloro-DL-alanine resistance by L-methionine-alpha-deamino-gamma-mercaptomethane-lyase activity

The antibacterial agent 3-chloro-DL-alanine (3CA) is an inhibitor of peptidoglycan synthesis. Fusobacterium nucleatum and Porphyromonas gingivalis, the bacteria responsible for oral malodor, are shown to be resistant to 1 mM 3CA, whereas Streptococcus mutans and Escherichia coli are sensitive to this antibacterial agent at the same concentration. We isolated the 3CA resistance gene from F. nucleatum and showed that the gene encodes an L-methionine-alpha-deamino-gamma-mercaptomethane-lyase that catalyzes the alpha,gamma-elimination of L-methionine to produce methyl mercaptan. The enzyme also exhibits 3CA chloride-lyase (deaminating) activity. This antibacterial agent is expected to be useful for specific selection of malodorous oral bacteria producing high amounts of methyl mercaptan.

Coherence incoherence and dimensional crossover in layered strongly correlated metals

The properties of an interacting electron system depend on the electron correlations and the effective dimensionality. For example, Coulomb repulsion between electrons may inhibit, or completely block, conduction by intersite electron hopping, thereby determining whether a material is a metal or an insulator. Furthermore, correlation effects increase as the number of effective dimensions decreases; in three-dimensional systems, the low-energy electronic states behave as quasiparticles, whereas in one-dimensional systems, even weak interactions break the quasiparticles into collective excitations. Dimensionality is particularly important for exotic low-dimensional materials where one- or two-dimensional building blocks are loosely connected into a three-dimensional whole. Here we examine two such layered metallic systems with angle-resolved photoemission spectroscopy and electronic transport measurements, and we find a crossover in the number of effective dimensions from two to three with decreasing temperature. This is apparent from the observation that, in the direction perpendicular to the layers, the materials have an insulating character at high temperatures but become metal-like at low temperatures, whereas transport within the layers remains metallic over the whole temperature range. We propose that this change in effective dimensionality correlates with the presence of coherent quasiparticles within the layers.

Methyl mercaptan production by periodontal bacteria

Oral malodour is principally caused by volatile sulphur compounds (VSC) such as hydrogen sulphide, methyl mercaptan and dimethyl sulphide. Methyl mercaptan is highly toxic, and its presence within a periodontal pocket suggests involvement in the induction and/or progression of periodontal disease. Methyl mercaptan is produced from L-methionine by L-methionine- alpha -deamino- gamma -mercaptomethane-lyase (METase). METase catalyses the alpha,gamma-eliminating reaction of L-methionine, which results in the release of alpha-ketobutyrate, methyl mercaptan and ammonia. Although methyl mercaptan is produced by a variety of microorganisms, Porphyromonas gingivalis is considered to be the most potent producer. METases of P. gingivalis have been characterised and the genes responsible for their production, the mg/genes, have been sequenced. To ascertain the role of METase in P. gingivalis pathogenicity, a METase-deficient mutant strain (M1217) from P. gingivalis strain W83 was engineered. Only 7.7% of the mice infected with W83 survived 4 days after subcutaneous injection, whereas 36% of the mice infected with M1217 survived over the same time period. Many papers have reported the periodontal pathogenesis of VSC. It has been argued that methyl mercaptan may play a significant role in the pathogenicity of P. gingivalis.

Hemiparkinsonism associated with a mesencephalic tumor

A 66-year-old woman presented with a 3-year history of progressive right-sided hemiparkinsonism manifested by a right-hand resting tremor and right-sided bradykinesia. Magnetic resonance imaging (MRI) of the brain revealed a non-enhanced polycystic mass in the left midbrain. (11)C-methylspiperone ((11)C-NMSP) and (18)F-fluorodopa ((18)F-DOPA) positron emission tomography (PET) revealed a striatal hypometabolism that was restricted to the left side. These findings are consistent with a dysfunction in the left nigrostriatal dopaminergic pathway that is presumably induced by the cystic mass in the left midbrain. This case is significant due to the paucity of reports regarding the occurrence of a relatively pure parkinsonism that is associated with a mesencephalic space-occupying lesion.

Correlation between oral malodor and periodontal bacteria

Volatile sulfur compounds (VSCs), including hydrogen sulfide, methyl mercaptan, and dimethyl sulfide, are primarily responsible for oral malodor. Recently, the mgl gene encoding L-methionine-alpha-deamino-gamma-mercaptomethane-lyase, which produces methyl mercaptan, was cloned from Porphyromonas gingivalis. This article discusses the mechanism and pathogenic role of the formation of VSCs by oral bacteria.

Hydrothermal synthesis of hydroxyapatite from natural source

Dicalcium phosphate dihydrate (DCPD) and anhydrous dicalcium phosphate (DCPA) extracted from a by-product in a manufacture of gelatin from bovine bone are used as starting materials for the hydrothermal synthesis of hydroxyapatite (HA) at temperatures of 160 and 200 degrees C under vapor pressures of 1 and 2 MPa, respectively. The suspension of DCPA with water gives a mixture of DCPA and HA as product but after adjusting the Ca/P molar ratio to 1.50 and 1.67 by addition of Ca(OH)(2), a single phase of HA with needle-like crystals is obtained. DCPA whiskers are produced in the suspension of DCPD with water but, on addition of Ca(OH)(2), the product obtained is again, a mixture of DCPA and HA. The coexistence of DCPA and HA is observed not only in the acidic region at pH 4.6 which is close to the known quasi-invariant point but also in the basic region at pH 12.3. Without addition of Ca(OH)(2) to the system, the complete conversion of DCPA or DCPD to HA is not possible.

Enhancement of CsLiB(6)O(10) surface-damage resistance by improved crystallinity and ion-beam etching

The surface laser-induced damage threshold (LIDT) of CsLiB(6)O(10) (CLBO) crystal was enhanced twofold with improved crystallinity and ion-beam etching. For crystals with high crystal quality (bulk LIDT, 15.0-19.0 GW/cm(2)), the surface LIDT was 1.4-fold higher than for those with conventional crystal quality (bulk LIDT, 9.0-12.0 GW/cm(2)). In addition, removal of residual surface-polishing compounds by means of ion-beam etching can further enhance the surface LIDT by another 1.5-fold. Thus, CLBO crystals with high crystal quality and ion-beam etching are now more reliable for high-power UV light generation.

L-Methionine-gamma-lyase, as a target to inhibit malodorous bacterial growth by trifluoromethionine

Methyl mercaptan is a major component responsible for oral malodor. This compound arises from the bacterial metabolism of methionine. Here we show that the growth of Porphyromonas gingivalis, a periodontal microorganism that produces large amounts of methyl mercaptan, was strongly inhibited by l-trifluoromethionine (TFM), a fluorinated derivative of methionine. In contrast, TFM had no effect on the growth of bacteria which do not produce methyl mercaptan. In addition, the survival rate of P. gingivalis-infected mice was remarkably increased by the co-injection of TFM. These results suggest that TFM is a promising antibacterial agent specific to the malodorous oral bacteria.

A molecular description of the gelation mechanism of konjac mannan

A molecular level description of the time course of the gelation of the polysaccharide konjac mannan (KM) is presented and the role of alkali addition is considered in detail. NMR relaxometry is utilized as a complementary methodology to mechanical spectroscopy in order to probe events occurring as a prelude to network formation, and high-resolution NMR is used to follow the deactetylation process. It is shown that the addition of alkali plays an important solubilizing role in addition to facilitating the deacetylation of the chain. Deacetylation is important both in reducing the inherent aqueous solubility of the polymer and in progressively negating the alkali-induced polyelectrolytic nature of the polysaccharide chain via reaction induced pH changes. It is proposed that observed induction periods following alkali addition (during which the elastic modulus does not rise) are not simply deacetylation delays but are related to the aggregation kinetics of the deacetylated material.

The relationship of left ventricular mass to endothelium-dependent vasodilation of the brachial artery in patients with hypertension

Although echocardiographically determined left ventricular mass and geometry predict cardiovascular morbid events in patients with hypertension, the mechanisms underlying this relation are unclear. There is considerable evidence that endothelium-dependent vasodilation is impaired in patients with hypertension. Thus, endothelial dysfunction may contribute to the mechanism that causes cardiovascular morbid events. This study was designed to examine the relationship between left ventricular geometry and endothelial function in patients with hypertension. The percentage increase in brachial arterial diameter during reactive hyperemia was examined by a high-resolution ultrasound technique in 49 patients with hypertension and 64 normotensive subjects. Patients with hypertension had an impairment of the percentage increase in brachial arterial diameter during reactive hyperemia and an increase in thiobarbituric acid-reactive substances (TBARS) compared to normotensive subjects (percentage increase in diameter 5.6 +/- 3.0 vs. 8.0 +/- 2.5%, p < 0.001; TBARS levels 6.1 +/- 1.3 vs. 5.3 +/- 1.0 nmol/ml, p < 0.001). In patients with hypertension, there was a significant correlation between the left ventricular mass index and the percentage increase in brachial arterial diameter during reactive hyperemia (r = -0.583, p < 0.001), and the percentage increase in brachial arterial diameter during reactive hyperemia varied with the pattern of left ventricular geometry (normal ventricular geometry: 7.7 +/- 2.6%; concentric remodeling: 5.2 +/- 2.3%; eccentric hypertrophy: 4.2 +/- 1.8%; concentric hypertrophy: 2.9 +/- 2.6%). We conclude that (1) flow-mediated endothelium-dependent vasodilation in the brachial artery is impaired in patients with hypertension, (2) a relationship exists between the left ventricular mass index and flow-mediated endothelium-dependent vasodilation in the brachial artery in patients with hypertension and (3) increased oxidative stress may play a role in the endothelial dysfunction in patients with hypertension.

Nociceptin inhibits excitatory but not inhibitory transmission to substantia gelatinosa neurones of adult rat spinal cord

Although intrathecal administration of nociceptin, an endogenous ligand of the opioid receptor-like1 receptor, exhibits an antinociceptive effect in various pain models, cellular mechanisms underlying this action are still unknown. Here, we investigated the effects of nociceptin on excitatory and inhibitory synaptic transmission to substantia gelatinosa neurones of an adult rat spinal cord slice with an attached dorsal root by use of the blind whole-cell patch-clamp technique; this was done under the condition of a blockade of a hyperpolarising effect of nociceptin. In about 70% of the neurones examined, nociceptin (1 microM) reduced the amplitude of glutamatergic excitatory postsynaptic currents (EPSCs) which were monosynaptically evoked by stimulating Adelta- or C-afferent fibres; the inhibition of C-fibre EPSCs (50+/-6%, n=11) was larger than that of Adelta-fibre EPSCs (30+/-5%, n=23; P<0.05). Each of the nociceptin actions was dose-dependent in a concentration range of 0.1 to 1 microM, and was largely suppressed by a selective opioid receptor-like1 receptor antagonist, 1-[(3R,4R)-1-cyclooctylmethyl-3-hydroxymethyl-4-piperidyl]-3-ethyl-1,3-dihydro-2H-benzimidazol-2-one (3 microM). Nociceptin (1 microM) also decreased miniature EPSCs frequency by 22+/-6% (n=7) while not affecting their amplitude. Responses of substantia gelatinosa neurones to bath-applied alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (10 microM) were not changed by nociceptin. Both electrically evoked and miniature inhibitory postsynaptic currents, mediated by either the GABA(A) or glycine receptor, were unaffected by nociceptin. These results indicate that nociceptin suppresses excitatory but not inhibitory synaptic transmission to substantia gelatinosa neurones through the activation of the opioid receptor-like1 receptor; this action is pre-synaptic in origin. Considering that the substantia gelatinosa is the main part of termination of Adelta- and C-fibres transmitting nociceptive information, the present finding would account for at least a part of the inhibitory action of nociceptin on pain transmission. Nociceptin could inhibit more potently slow-conducting than fast-conducting pain transmission.