Panretinal Photocoagulation Using Short-Pulse Laser Induces Less Inflammation and Macular Thickening in Patients with Diabetic Retinopathy

We compared the effect of panretinal photocoagulation (PRP) using short-pulse laser (SPL) and conventional laser, regardless of the number of spots, in terms of their effect on the progression of diabetic macular edema (DME) and anterior flare intensity (AFI) in patients with high-risk nonproliferative diabetic retinopathy (non-PDR). Forty-two eyes of 42 patients were subjected to PRP using the conventional argon laser (Conv group) or SPL (SPL group). CRT and AFI levels in the SPL group were significantly lower than those in the Conv group (CRT at 4, 6, and 10 weeks; AFI at 6, 10, and 18 weeks). Eyes of rabbits were photocoagulated using conventional laser with 500 spots (Conv 500s), SPL with 500 spots (SPL 500s), or 1000 spots (SPL 1000s). Vascular endothelial growth factor (VEGF), interleukin-6 (IL-6), intercellular adhesion molecule-1 (ICAM-1), and monocyte chemotactic protein-1 (MCP-1) levels in vitreous humor were measured using an immunoassay. Compared to conventional laser, VEGF, IL-6, and MCP-1 levels were significantly lower in the SPL 1000s and SPL 500s groups. In patients with high-risk non-PDR, SPL has a greater preventive effect on the progression of DME and AFI and produces less inflammatory cytokines than conventional lasers

Effect of intravitreal triamcinolone acetonide injection at the end of vitrectomy for vitreous haemorrhage related to proliferative diabetic retinopathy

Background/Aims To investigate whether intravitreal injection of triamcinolone acetonide (IVTA) combined with vitrectomy prevents postoperative inflammation in patients with vitreous haemorrhage (VH) due to proliferative diabetic retinopathy (PDR). Methods This prospective, multicentre, randomised study conducted at seven sites in Japan enrolled patients diagnosed as having VH following PDR. Patients underwent vitrectomy with (IVTA+VIT group) or without (VIT group) IVTA at the end of the surgery. Anterior flare intensity (AFI), central retinal thickness (CRT), best-corrected visual acuity (BCVA) and intraocular pressure (IOP) were measured before and at 3 days, 1 week, 1, 3 and 6 months after surgery and compared. Results Number of patients who completed 6 months of follow-up was 40 and 41 in VIT group and IVTA+VIT group, respectively. AFI was significantly higher in the VIT group than in the IVTA+VIT group at 3 days (P=0.033), 1 week (P=0.019) and 1 month (P=0.037). There were no significant differences in CRT, BCVA and IOP between the groups through the observational periods. In the cases with macular oedema >350 µm of CRT at 3 days, CRT was significantly lower in the IVTA+VIT group than in the VIT group at 1 month (P=0.041). Conclusions IVTA combined with vitrectomy and cataract surgery contributed to inhibit the postoperative inflammation in patients with VH due to PDR. The effect of IVTA in the reduction of diabetic macular oedema may be limited to the early stage after surgery

Direct Photocoagulation Guided by Merged Retinal Images for the Treatment of Focal Diabetic Macular Edema

Purpose. To introduce a novel laser photocoagulation (PC) protocol named merged image-guided PC (MIG-PC), which included merging the images of the fundus, optical coherence tomography (OCT) map, and fluorescein angiography (FA). We compared the anatomical and functional results between MIG-PC and FA-guided PC (FG-PC) for the treatment of focal diabetic macular edema (DME). Method. We examined the treatment outcomes in 27 consecutive eyes treated with MIG-PC compared with 28 matched eyes treated with FG-PC. We identified the microaneurysms (MAs) located in the focal edema areas and ablated them using focal PC. Best-corrected visual acuity (BCVA) and retinal thickness (RT) measured using OCT were compared between the groups at baseline and 2, 4, 8, 12, and 24 weeks after treatment. Results. The foveal and perifoveal RT were reduced after treatment in both the groups, and the perifoveal RT in the MIG-PC group was significantly lower than that in the FG-PC group at 4 weeks and thereafter. BCVA in the MIG-PC group was significantly higher than that in the FG-PC group at 12 and 24 weeks. The numbers of laser spots (p=0.0001), additional laser treatments (p=0.0121), and intravitreal injection of ranibizumab (p=0.0012) in the MIG-PC group were significantly lower than those in the FG-PC group (Mann–Whitney test). Conclusion. MIG-PC contributed to the improvement in BCVA and reduction in RT, number of laser shots required, and retreatment rates. Based on our data, MIG-PC can be recommended for the treatment of focal DME. This trial is registered with ID UMIN000030390

Crystal structure of a Ca2+-dependent regulator of flagellar motility reveals the open-closed structural transition

Sperm chemotaxis toward a chemoattractant is very important for the success of fertilization. Calaxin, a member of the neuronal calcium sensor protein family, directly acts on outer-arm dynein and regulates specific flagellar movement during sperm chemotaxis of ascidian, Ciona intestinalis. Here, we present the crystal structures of calaxin both in the open and closed states upon Ca2+ and Mg2+ binding. The crystal structures revealed that three of the four EF-hands of a calaxin molecule bound Ca2+ ions and that EF2 and EF3 played a critical role in the conformational transition between the open and closed states. The rotation of α7 and α8 helices induces a significant conformational change of a part of the α10 helix into the loop. The structural differences between the Ca2+- and Mg2+-bound forms indicates that EF3 in the closed state has a lower affinity for Mg2+, suggesting that calaxin tends to adopt the open state in Mg2+-bound form. SAXS data supports that Ca2+-binding causes the structural transition toward the closed state. The changes in the structural transition of the C-terminal domain may be required to bind outer-arm dynein. These results provide a novel mechanism for recognizing a target protein using a calcium sensor protein

Asymmetric desymmetrization of meso-vic-diols by carbamoylation catalyzed with a chiral Cu(II) complex

Asymmetric desymmetrization of meso-vic-diols was achieved by carbamoylation in the presence of copper triflate and (S,S)-Ph-BOX as a catalyst without any use of bases. The method was successfully applied to asymmetric desymmetrization of five- to eight-membered cyclic meso-vic-diols in high enantioselectivity with up to 93% ee

Outburst of LS V+44 17 Observed by MAXI and RXTE, and Discovery of a Dip Structure in the Pulse Profile

We report on the first observation of an X-ray outburst of a Be/X-ray binary pulsar LS V +44 17/RX J0440.9+4431, and the discovery of an absorption dip structure in the pulse profile. An outburst of this source was discovered by MAXI GSC in 2010 April. It was the first detection of the transient activity of LS V +44 17 since the source was identified as a Be/X-ray binary in 1997. From the data of the follow-up RXTE observation near the peak of the outburst, we found a narrow dip structure in its pulse profile which was clearer in the lower energy bands. The pulse-phase-averaged energy spectra in the 3$-$100 keV band can be fitted with a continuum model containing a power-law function with an exponential cutoff and a blackbody component, which are modified at low energy by an absorption component. A weak iron K$\alpha$ emission line is also detected in the spectra. From the pulse-phase-resolved spectroscopy we found that the absorption column density at the dip phase was much higher than those in the other phases. The dip was not seen in the subsequent RXTE observations at lower flux levels. These results suggest that the dip in the pulse profile originates from the eclipse of the radiation from the neutron star by the accretion column.Comment: 18 pages, 7 figures, accepted for publication in PAS

Wheat‐ghretropins: novel ghrelin‐releasing peptides derived from wheat protein

Ghrelin is an endogenous orexigenic hormone mainly produced by stomach cells and is reported to influence appetite, gastrointestinal motility and growth hormone secretion. We observed that enzymatic digest of wheat gluten stimulated ghrelin secretion from mouse ghrelinoma 3-1, a ghrelin-releasing cell line. Further on, we characterized the ghrelin-releasing peptides present in the digest by comprehensive peptide analysis using liquid chromatography-mass spectrometry and structure-activity relationship. Among the candidate peptides, we found that SQQQQPVLPQQPSF, LSVTSPQQVSY and YPTSL stimulated ghrelin release. We then named them wheat-ghretropin A, B and C, respectively. In addition, we observed that wheat-ghretropin A increased plasma ghrelin concentration and food intake in mice after oral administration. Thus, we demonstrated that wheat-ghretropin stimulates ghrelin release both in vitro and in vivo. To the best of our knowledge, this is the first report of a wheat-derived exogenous bioactive peptide that stimulates ghrelin secretion

Long-term Monitoring of the Black Hole Binary GX 339-4 in the High/Soft State during the 2010 Outburst with MAXI/GSC

We present the results of monitoring the Galactic black hole candidate GX 339-4 with the Monitor of All-sky X-ray Image (MAXI) / Gas Slit Camera (GSC) in the high/soft state during the outburst in 2010. All the spectra throughout the 8-month period are well reproduced with a model consisting of multi-color disk (MCD) emission and its Comptonization component, whose fraction is <= 25% in the total flux. In spite of the flux variability over a factor of 3, the innermost disk radius is constant at R_in = 61 +/- 2 km for the inclination angle of i = 46 deg and the distance of d=8 kpc. This R_in value is consistent with those of the past measurements with Tenma in the high/soft state. Assuming that the disk extends to the innermost stable circular orbit of a non-spinning black hole, we estimate the black hole mass to be M = 6.8 +/- 0.2 M_sun for i = 46 deg and d = 8 kpc, which is consistent with that estimated from the Suzaku observation of the previous low/hard state. Further combined with the mass function, we obtain the mass constraint of 4.3 M_sun < M < 13.3 M_sun for the allowed range of d = 6-15 kpc and i < 60 deg. We also discuss the spin parameter of the black hole in GX 339-4 by applying relativistic accretion disk models to the Swift/XRT data.Comment: 9 pages, 8 figures, accepted for publication in PASJ (Suzaku+MAXI special issue

A Spectral Study of the Black Hole Candidate XTE J1752-223 in the High/Soft State with MAXI, Suzaku and Swift

We report on the X-ray spectral analysis of the black hole candidate XTE\ J1752--223 in the 2009--2010 outburst, utilizing data obtained with the MAXI/Gas Slit Camera (GSC), the Swift/XRT, and Suzaku, which work complementarily. As already reported by Nakahira et al. (2010) MAXI monitored the source continuously throughout the entire outburst for about eight months. All the MAXI/GSC energy spectra in the high/soft state lasting for 2 months are well represented by a multi-color disk plus power-law model. The innermost disk temperature changed from $\sim$0.7 keV to $\sim$0.4 keV and the disk flux decreased by an order of magnitude. Nevertheless, the innermost radius is constant at $\sim$41 $D_{3.5}(\cos{\it i})^{-1/2}$ km, where $D_{3.5}$ is the source distance in units of 3.5 kpc and $i$ the inclination. The multi-color disk parameters obtained with the MAXI/GSC are consistent with those with the Swift/XRT and Suzaku. The Suzaku data also suggests a possibility that the disk emission is slightly Comptonized, which could account for broad iron-K features reported previously. Assuming that the obtained innermost radius represents the innermost stable circular orbit for a non-rotating black hole, we estimate the mass of the black hole to be 5.51$\pm$0.28 $M_{\odot}$ $D_{3.5}(\cos{\it i})^{-1/2}$, where the correction for the stress-free inner boundary condition and color hardening factor of 1.7 are taken into account. If the inclination is less than 49$^{\circ}$ as suggested from the radio monitoring of transient jets and the soft-to-hard transition in 2010 April occurred at 1--4% of Eddignton luminosity, the fitting of the Suzaku spectra with a relativistic accretion-disk model derives constraints on the mass and the distance to be 3.1--55 $M_{\odot}$ and 2.3--22 {\rm kpc}, respectively. This confirms that the compact object in XTE J1752--223 is a black hole.Comment: 12 pages including 7 figures and 4 tables, accepted for publication in PAS