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Splanchnic blood flow changes dramatically after meal ingestion. The present study evaluated physiologic interactions between meal ingestion and hemodynamics with respect to renal blood flow on duplex sonography, assessing the possible influence on Doppler parameters used as diagnostic criteria for renal artery stenosis. Subjects comprised 26 healthy young men (mean age: 22 ± 2 y). Sonographic measurements were made shortly after breakfast and every 1 h thereafter and were compared with values measured before the meal. Peak systolic velocity in the renal artery was elevated post-prandially, peaking at 1 h (90 ± 12 cm/s), compared with pre-prandially (73 ± 10 cm/s, p < 0.01). Similarly, acceleration time at the intra-renal segmental artery shortened to a minimum at 1 h (45 ± 5 ms) compared with baseline (51 ± 6 ms, p < 0.01). The present study indicates that renal blood flow is altered for a few hours after meal ingestion. Attention should be paid to the interpretation of data measured after meals on duplex sonography for diagnosis of renal artery stenosis.

Background Candida species are clinically important causes of bloodstream infections because their mortality is very high. Given that some species of Candida are azole-resistant, identifying the distributions of Candida species could facilitate the formulation of an appropriate empirical antifungal therapy. It has been shown that the distribution varies depending on the continent, country, city, and hospital. In this paper, we describe the distributions of species in hospitals in northern Osaka, Japan. Method We evaluated blood culture results obtained from six tertiary hospitals in the northern Osaka area between 2004 and 2011. We also obtained comorbidity information from the patients' hospital medical records. Kaplan–Meier curves were drawn to compare the risk of death related to the different species. Results Of the 165 cases of candidemia confirmed by blood culture, 66% were male and the mean age was 62 years (range = 0–96). Overall, Candida albicans comprised 70 cases (43%), followed by Candida parapsilosis with 36 cases (22%), Candida glabrata with 25 cases (15%), Candida tropicalis with 11 cases (7%), Candida krusei with 10 cases (6%), and other Candida species with 13 cases (8%). C. tropicalis had higher associated mortality than other species, although it was not statistically significant. Conclusions C. albicans was the most frequently isolated species, but the proportion of non-albicans Candida species was not negligible. The relatively high frequency of non-albicans Candida species distinguished the Japanese distribution from other areas. This characteristic distribution may have important implications when formulating an empirical antifungal therapy for Japanese clinical practice.

Nonfibrillar assemblies of amyloid β-protein (Aβ) are considered to play primary roles in Alzheimer disease (AD). Elucidating the assembly pathways of these specific aggregates is essential for understanding disease pathogenesis and developing knowledge-based therapies. However, these assemblies cannot be monitored in vivo, and there has been no reliable in vitro monitoring method at low protein concentration. We have developed a highly sensitive in vitro monitoring method using fluorescence correlation spectroscopy (FCS) combined with transmission electron microscopy (TEM) and toxicity assays. Using Aβ labeled at the N terminus or Lys(16), we uncovered two distinct assembly pathways. One leads to highly toxic 10-15-nm spherical Aβ assemblies, termed amylospheroids (ASPDs). The other leads to fibrils. The first step in ASPD formation is trimerization. ASPDs of ∼330 kDa in mass form from these trimers after 5 h of slow rotation. Up to at least 24 h, ASPDs remain the dominant structures in assembly reactions. Neurotoxicity studies reveal that the most toxic ASPDs are ∼128 kDa (∼32-mers). In contrast, fibrillogenesis begins with dimer formation and then proceeds to formation of 15-40-nm spherical intermediates, from which fibrils originate after 15 h. Unlike ASPD formation, the Lys(16)-labeled peptide disturbed fibril formation because the Aβ(16-20) region is critical for this final step. These differences in the assembly pathways clearly indicated that ASPDs are not fibril precursors. The method we have developed should facilitate identifying Aβ assembly steps at which inhibition may be beneficial.

Activity improvement of an antimicrobial peptide, thanatin, has been achieved up to 4-fold higher than natural original one by site-specific chemical modifications with tert-butyl group at two cysteine residues which form an intramoleular disulfide bridge. The chemically modified thanatin (C11tBu/C18tBu) exhibited improved antimicrobial activity toward Gram-positive bacteria, Micrococcus luteus, whereas lowered activity toward Gram-negative bacteria, Escherichia coli. This finding suggests that disulfide-bridge formation is not only indispensable for exhibition of antimicrobial activity of thanatin but also closely related to the activity specificity towards bacteria. NMR analysis indicates that thanatin acts against E.coli stereospecifically by taking advantage of its C-terminal beta-hairpin structure, while the activity against M. luteus does not relate to structures and correlates very well to side-chain hydrophobicity.

We report our recent progress on GaN-based laser diodes (LDs) which will be applied as a light source in high-density optical storage systems. Recently we achieved a lifetime of more than 500 hours under continuous-wave operation with a constant power 20 mW at 25°C using GaN-based LDs with a standard ridge structure. We also report the potential of GaN-based LDs with another structure of a buried-ridge. The far-field pattern of the LDs with a buried-ridge structure strongly depended on the Al content of the AlxGa1−xN burying layer. This dependency showed that the device characteristics change from gain-guiding to refractive index-guiding. The critical point was around x=0.30 of an Al content which corresponds to Δn=0.007 of a lateral index step. It was, therefore, found that the optical transverse mode can be controlled by adjusting the Al content of the AlxGa1−xN burying layer.

The buried-ridge structure was introduced to GaN-based laser diodes for the purpose of realizing an index-guided structure in order to control the difference of effective refractive indexes between the inside and outside of the lasing area and to stabilize the lasing mode. Low-temperature-grown Al x Ga (1− x ) N was used as the burying layer, and it was found that the refractive-index difference can be controlled by adjusting the Al content in the Al x Ga (1− x ) N burying layer independent of the ridge dimensions. As a result of fabricating LDs with different Al contents, we found that Al content should be more than 30% in order to form an index-guided structure. The optimum refractive-index difference was estimated by fitting with the calculation. The LD with a buried-ridge structure, in which Al in the burying layer was more than 30%, had desirable properties as an index-guided waveguide.

In AlGaN growth using low-pressure metalorganic chemical vapor deposition the TMA-flow-rate dependence and reactor-pressure dependence on the Al content were investigated. We found that the reduction of partial pressure of TMA is effective in preventing the reduction of the Al content. To apply AlN and AlGaN films to devices, we fabricated an insulated gate heterostructure field effect transistor (IG-HFET). The AFM image of 4 nm-thick AlN on GaN shows a rough surface composed of approximately 500 nm-size grains. The grain boundary may be the origin of the leakage current between gate and drain during the operation of the IG-HFET. Nevertheless, the device can operate with transconductance gm of 235 mS mm−1 for Lg=1.4 μm.

The well-number dependence of the optical pumping threshold power for stimulated emission of GaInN multiple quantum-well (MQW) laser structures was investigated. The pumping threshold power for a three GaInN MQW sample was found to be as low as 33 kW/cm 2 at room temperature. The room-temperature pulsed operation of a five GaInN MQW laser diode (LD), whose number of wells was determined based on the optical pumping experiment, was also demonstrated. The lowest threshold current density was 9.5 kA/cm 2 . The lasing wavelength was 417.5 nm with a full-width at half-maximum (FWHM) less than the spectrum resolution of 0.2 nm.

The photoreaction of Kemp's imide-linked coumarin 1 and thymine 3 gave two crossadducts, cis-syn 4 cis-anti 5. The yield and ratio of 45 in benzene solution remarkably increased by factors of 4.2 and 10 than those in acetonitrile solution, respectively. On the other hand, the reaction of acetoxycoumarin 2 and 3 gave only the cis-anti crossadduct in each solution.

We examined the effect of HSR-81 ((-)-(R)-alpha-[(tert-butylamino)methyl]-2-chloro-4-hydroxybenzyl alcohol L-tartrate), a newly developed, potent and selective beta 2-adrenoceptor agonist, as well as ritodrine and isoproterenol, on the spontaneous rhythmic contraction in uteri isolated from late pregnant, middle pregnant and non-pregnant (dioestrous and oestrous) rats. The three agonists inhibited the spontaneous rhythmic contraction at all the stages in a concentration-dependent manner. The pD2 value for HSR-81 was greater in late pregnancy than in dioestrus and oestrus. In the uterine preparations of late pregnancy and dioestrus, ICI-118,551 (1-(7-methylindan-4-yloxy)-3-isopropyl-aminobutan-2-ol , a selective beta 2-adrenoceptor antagonist) and atenolol (a selective beta 1-adrenoceptor antagonist) produced a parallel rightward shift of the concentration-response curves for HSR-81. The pKB values for ICI-118,551 and atenolol suggest that the inhibitory effect of HSR-81 was mediated through beta 2-adrenoceptors in the two stages. In the membranes prepared from rat uteri in late pregnancy and dioestrus, the equilibrium dissociation constant for [125I]iodocyanopindolol binding was not significantly different between the two stages. The three beta-adrenoceptor agonists and the two antagonists competed for the specific [125I]iodocyanopindolol binding and the pKi values were not significantly different between the two stages. However, the maximum number of binding sites was significantly greater in late pregnancy than in dioestrus. The configuration of the competition curves and the pKi values for the two antagonists confirmed the fact that these membranes contain predominantly beta 2-adrenoceptor subtype. These results indicate that the potent inhibition of the spontaneous rhythmic contraction by HSR-81 in the pregnant uterus may be due to the increased number of beta 2-adrenoceptors.

In the presence of adrenergic and cholinergic blocking agents, transmural electrical stimulation evoked a relaxation in isolated dog urethra precontracted with histamine. The response was abolished by tetrodotoxin, indicating its neurogenic origin. The non-adrenergic and non-cholinergic relaxation developed rapidly and was transient at low stimulation frequencies (⪯ 1 Hz). However, at higher frequencies (⪰ 5 Hz ) the recovery phase of the relaxation became slow and often showed a notch, suggesting the presence of transient and slow components. NG-Monomethyl-L-arginine, a nitric oxide synthase inhibitor, inhibited the transient relaxation but did not affect the relaxation evoked at high stimulation frequencies. NG-Nitro-L-arginine, a more potent nitric oxide synthase inhibitor, abolished the transient relaxation produced at low stimulation frequencies and markedly attenuated the transient component at high frequencies. However, NG-nitro-L-arginine did not affect the slow component. The inhibition by NG-monomethyl-L-arginine and NG-nitro-L-arginine was reversed by the addition of L- but not D-arginine. Exogenously applied vasoactive intestinal polypeptide (VIP) produced a slowly developing relaxation. The slow relaxation induced by transmural electrical stimulation and VIP was not affected by [4-Cl-D-Phe6, Leu17]VIP, a reportedly competitive VIP antagonist. NG-Nitro-L-arginine did not effect the relaxation induced by VIP and sodium nitroprusside. These results suggest that the non-adrenergic and non-cholinergic relaxation induced by transmural electrical stimulation is composed of nitric oxide-dependent and -independent components in the isolated dog urethra.

The pharmacological profile of a newly synthesized imidazole derivative, DJ-7141, was examined with special reference to alpha-2 adrenoceptors. In the rat vas deferens and dog mesenteric artery, DJ-7141 at concentrations over 10−9 M selectively acted on the presynaptic alpha-2 adrenoceptors on the sympathetic nerve terminals and inhibited the contractions induced by electrical transmural stimulation. The potency of DJ-7141 was almost the same as those of clonidine and guanabenz. DJ-7141 also acted on the postsynaptic alpha-2 adrenoceptors to contract the dog saphenous vein. However, no alpha-1 agonist and antagonist actions were found at concentrations showing presynaptic alpha-2 agonist activity. In contrast to DJ-7141, clonidine produced an apparent contraction in the dog mesenteric artery, and the response was inhibited by prazosin. In urethane-anesthetized rats, clonidine at doses ranging from 0.003 mg/kg to 0.03 mg/kg produced a marked and prolonged hypotension, while DJ-7141 at such doses failed to produce a reduction of blood pressure. From these results, it is suggested that, in contrast to clonidine and other alpha-2 agonists, DJ-7141 is a unique alpha-2 agonist which shows high affinity to peripheral alpha-2 adrenoceptors but only a mild hypotensive activity.