Y Sato

Yamanashi University, Kōfu-shi, Yamanashi-ken, Japan

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Publications (21)49.76 Total impact

  • Article: 28 effect of trichostatin a on in vitro embryo development of interspecies nuclear transfer embryos reconstructed from cat donor nuclei and bovine cytoplasm.
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    ABSTRACT: Interspecies somatic cell nuclear transfer (iSCNT) is an invaluable tool for studying nucleus-cytoplasm interactions and may provide an alternative for cloning endangered animals whose oocytes are difficult to obtain. The developmental ability of iSCNT embryos decreases with increases in taxonomic distance between the donor and recipient species. The development of cat-bovine iSCNT embryos is reportedly blocked at the 8-cell stage (Thongphakdee et al. 2008 J. Reprod. Dev. 54, 142-147). Abnormal epigenetic reprogramming, such as DNA methylation or histone modifications, may cause low iSCNT efficiencies. The present study was conducted to evaluate the effect of the histone deacetylase inhibitor trichostatin A (TSA), previously used to enhance nuclear reprogramming following SCNT, on the developmental ability of cat iSCNT embryos using bovine oocytes matured in vitro. The matured bovine oocyte was enucleated by the glass needle and the domestic cat fetal fibroblast used as the donor nuclei was then placed into the perivitelline space adjacent to the plasma membrane of the oocyte. Couplets with bovine ooplasm were fused and activated simultaneously with a single DC pulse of 2.3kVcm(-1) for 30µs, respectively, using an electro cell fusion generator followed by cycloheximide treatment. Reconstructed cat-bovine embryos were treated with 0, 25, 50, and 100nM concentrations of TSA for 24h following fusion. The percentages of embryos cleaved and embryos developed to the blastocyst stage were subjected to arc sin transformation before ANOVA. The TSA treatment at 50nM contributed significantly higher rates of cleavage and blastocyst formation (n=139; 84.3 and 4.6%, respectively) compared with untreated embryos (n=187; 63.8 and 0%, respectively) and embryos treated with 100nM TSA (n=172; 71.4 and 0%, respectively; P<0.05). Development to the morula stage of iSCNT embryos was observed in the TSA treatment groups, whereas no embryos developed beyond the 16-cell stage in the untreated group. In conclusion, our results indicate that TSA treatment for 24h following fusion improves the development of iSCNT embryos. Specifically, 50nM TSA treatment provides a beneficial effect on cleavage and development to the blastocyst stage of cat iSCNT embryos using bovine oocytes matured in vitro as recipients and domestic cat fibroblasts as donor nuclei.
    Reproduction Fertility and Development 12/2012; 25(1):161. · 2.11 Impact Factor
  • Article: Search for the Θ^{+} Pentaquark via the π^{-}p→K^{-}X Reaction at 1.92  GeV/c.
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    ABSTRACT: The Θ^{+} pentaquark baryon was searched for via the π^{-}p→K^{-}X reaction with a missing mass resolution of 1.4  MeV/c^{2} (FWHM) at the Japan Proton Accelerator Research Complex (J-PARC). π^{-} meson beams were incident on the liquid hydrogen target with a beam momentum of 1.92  GeV/c. No peak structure corresponding to the Θ^{+} mass was observed. The upper limit of the production cross section averaged over the scattering angle of 2° to 15° in the laboratory frame is obtained to be 0.26  μb/sr in the mass region of 1.51-1.55  GeV/c^{2}. The upper limit of the Θ^{+} decay width is obtained to be 0.72 and 3.1 MeV for J_{Θ}^{P}=1/2^{+} and J_{Θ}^{P}=1/2^{-}, respectively, using the effective Lagrangian approach.
    Physical Review Letters 09/2012; 109(13):132002. · 7.37 Impact Factor
  • Article: Chronic microstimulation of cat auditory cortex effective to evoke detection behaviors.
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    ABSTRACT: The purpose of this study was to clarify stimulus pulse parameters effective to elicit behaviors of cats trained to detect electric pulse stimuli through chronically implanted electrodes in the primary auditory cortex. One or two pulse parameters were systematically shifted from the standard stimulus consisting of constant-current pulses of amplitude 80 μA, duration 0.2 ms, number of pulses 33, and rate 200 Hz (compatible with interpulse interval 5 ms). Interaction between the pulse amplitude and pulse duration was investigated: although the proportion of stimulus detection responses increased with increasing phase charge (pulse amplitude×pulse duration), a combination of relatively high amplitude during short pulse duration elicited a higher proportion of detection responses when phase charge was constant. Interaction between the number of pulses and interpulse intervals was investigated. We found that the proportion of detection responses is explained by the linear function of two factors, overall charge (phase charge×the number of pulses) and train duration: the proportion of detection responses increased with increasing overall charge and decreasing train duration. Interaction between pulse amplitude and the number of pulses was investigated. We again found that the proportion of detection responses is explained by the linear function of overall charge and train duration in the amplitude-number shift paradigm. Thus, the behavior performance (proportion of detection responses) is a linear time function of overall charge and train duration regardless of the stimulus paradigm. We believe that the findings will contribute to the development of auditory cortex implants for transfer of auditory information directly to the brain.
    Neuroscience 03/2012; 206:81-8. · 3.38 Impact Factor
  • Article: Search for the $\Theta^{+}$ pentaquark via the $\pi^-p\to K^-X$ reaction at 1.92 GeV/$c$
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    ABSTRACT: The $\Theta^+$ pentaquark baryon was searched for via the $\pi^-p\to K^-X$ reaction in a missing-mass resolution of 1.4 MeV/$c^2$(FWHM) at J-PARC. $\pi^-$ meson beams were incident on the liquid hydrogen target with the beam momentum of 1.92 GeV/$c$. No peak structure corresponding to the $\Theta^+$ mass was observed. The upper limit of the production cross section averaged over the scattering angle of 2$^{\circ}$ to 15$^{\circ}$ in the laboratory frame was obtained to be 0.26 $\mu$b/sr in the mass region of 1.51$-$1.55 GeV/$c^2$.The upper limit of the $\Theta^+$ decay width using the effective Lagrangian approach was obtained to be 0.72 MeV/$c^2$ and 3.1 MeV/$c^2$ for $J^P_{\Theta}=1/2^+$ and $J^P_{\Theta}=1/2^-$, respectively.
    03/2012;
  • Article: The inferior mesenteric vein to the left gonadal vein shunt for gastroesophageal varices and extrahepatic portal vein thrombosis after living donor liver transplantation: a case report.
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    ABSTRACT: This 59-year-old woman underwent living donor liver transplantation using a left lobe graft as an aid for autoimmune hepatitis in 2003. Splenectomy was also performed because of blood type incompatibility. Follow-up endoscopic and computed tomography examinations showed gastroesophageal varices with extra hepatic portal vein thrombosis in 2007 that increased (esophageal varices [EV]: locus superior [Ls], moderately enlarged, beady varices [F2], Blue varices [Cb], presence of small in number and localized red color sign [RC1] and telangiectasia [TE+], gastric varices [GV]: extension from the cardiac orifice to the fornix [Lg-cf], moderately enlarged, beady varices [F2], white varices [Cw], absence of red color sign [RC-]). Portal venous flow to the gastroesophageal varices was also confirmed from a large right gastric vein. The splenic vein was thrombosed. Blood flow to the liver graft was totally supplied from the hepatic artery. The graft was functioning well. Because these gastroesophageal varices had a high risk of variceal bleeding, we decided to proceed with a portal reconstruction of a surgical portosystemic shunt in 2008. Severe adhesions were observed around the portal vein. It was impossible to perform portal reconstruction. There were relatively fewes adhesious in the left lower side of the abdominal cavity. We decided to create an inferior mesenteric vein to left gonadal vein shunt. The portal vein pressure decreased from 31.0 to 21.5 cm H2O thereafter. The postoperative course was smooth without any complication. This patient was discharged on the postoperative day 15. Follow-up endoscopic study showed the improvement in the gastroesophageal varices (EV: Ls, F2, Cb, RC(-), GV: Lg-c, F2, Cw, RC-) at 3 months after the operation. We also comfirmed the patency of the shunt by serial computed tomography examinations.
    Transplantation Proceedings 03/2012; 44(2):591-3. · 1.00 Impact Factor
  • Article: De novo ulcerative colitis and autoimmune hepatitis after living related liver transplantation from cytomegalovirus-positive donor to cytomegalovirus-negative recipient: a case report.
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    ABSTRACT: De novo autoimmune hepatitis (AIH) after liver transplantation (OLT) has been reported; however, de novo ulcerative colitis (UC) combined with AIH after OLT is rare. We report a patient who suffered de novo UC with AIH after living related OLT (LRLT) due to fulminant hepatitis using a cytomegalovirus (CMV)-positive donor to a CMV-negative recipient. A 32-year-old man underwent LRLT due to fuluminant hepatis 4 years prior. He was admitted for colitis with diarrhea, abdominal pain, and high fever in March 2010. The abdominal computed tomography revealed severe jejunal edema. Anti-infectious therapies for bacterial, fungal, and CMV cases were ineffective. Small bowel endoscopy demonstrated erosion, redness, ulceration, and edema from the stomach to the jejunum. However, the origin of the colitis was not clear. Thereafter he displayed melena with a high fever and abdominal pain. The colon revealed diffuse inflammation with pseudopolyposis. De novo UC or CMV infection was suspected. His symptoms improved upon administration of salazopyrin and denosine. Moreover, he suffered de novo AIH, which was diagnosed by liver biopsy 3 months after the de novo UC. Steroid therapy improved the AIH. It has been reported that CMV is involved with UC and rejection. Our case suggested that CMV might induce de novo UC or AIH in CMV-negative recipients.
    Transplantation Proceedings 03/2012; 44(2):570-3. · 1.00 Impact Factor
  • Article: A simple and versatile data acquisition system for software coincidence and pulse-height discrimination in 4πβ-γ coincidence experiments.
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    ABSTRACT: A simple but versatile data acquisition system for software coincidence experiments is described, in which any time stamping and live time controller are not provided. Signals from β- and γ-channels are fed to separately two fast ADCs (16 bits, 25 MHz clock maximum) via variable delay circuits and pulse-height stretchers, and also to pulse-height discriminators. The discriminating level was set to just above the electronic noise. Two ADCs were controlled with a common clock signal, and triggered simultaneously by the logic OR pulses from both discriminators. Paired digital signals for each sampling were sent to buffer memories connected to main PC with a FIFO (First-In, First-Out) pipe via USB. After data acquisition in list mode, various processing including pulse-height analyses was performed using MS-Excel (version 2007 and later). The usefulness of this system was demonstrated for 4πβ(PS)-4πγ coincidence measurements of (60)Co, (134)Cs and (152)Eu. Possibilities of other extended applications will be touched upon.
    Applied radiation and isotopes: including data, instrumentation and methods for use in agriculture, industry and medicine 03/2012; 70(9):2031-6. · 1.09 Impact Factor
  • Article: Isolated dissection of the superior mesenteric artery after living donor liver transplantation: a case report.
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    ABSTRACT: Isolated dissection of the superior mesenteric artery (SMA) not associated with aortic dissection is rare, particularly after living donor liver transplantation (LDLT). We experienced a case of isolated dissection of the SMA after LDLT performed in a 56-year-old man diagnosed with hepatitis B virus-related cirrhosis and hepatocellular carcinoma within the Milan criteria. He had no past history of hypertension or diabetes mellitus. At 6 days after LDLT, the patient underwent an emergency portal vein thrombectomy with ligation of a huge left gastric vein shunt. Thereafter anticoagulant and antiplatelet therapy were initiated. At 12 days after LDLT, a contrast-enhanced computer assisted tomography (CT) scan revealed the presence of a thrombus in a false lumen and a thin flap enlarged in the SMA. Because he presented neither abdominal pain nor biochemical data suggesting mesenteric ischemia, he was treated with antihypertensive agents in addition to anticoagulant and antiplatelet therapy. The thrombus in the false lumen was reduced and the intimal flap in the SMA disappeared according to the results of a CT scan 4 months after LDLT. He has remained free of symptoms for 4 years. The strategy to treat isolated SMA dissection is not well established. Urgent surgery is indicated for acute symptomatic forms with a suspicion of mesenteric ischemia; conservative treatment is indicated for patients with minimal, resolving, or no pain, but requires close follow-up.
    Transplantation Proceedings 03/2012; 44(2):588-90. · 1.00 Impact Factor
  • Article: Regulatory T-cell activation among patients who displayed operational tolerance following intra-portal administration of donor-specific antigens in living donor liver transplantation.
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    ABSTRACT: Immunologic tolerance is the goal for all transplant surgeons. We have reported that repeated donor-specific antigen transfusion (DST) via the portal vein allowed rapid reduction of immunosuppressants with decreased acute cellular rejection episodes among living donor liver transplantations (LDLT). Moreover, we demonstrated that intraportal DST induced macrochimerism of donor type CD56+ T cells in the liver graft. We examined the impact of FoxP3+CD4+CD25+ T cells in recipients who acquired almost tolerance after LDLT with intraportal DST. We defined the amount of immunosuppressants administered less than one time per week as "almost tolerance" after LDLT, which occurred among 14% of DST patients after adult-to-adult LDLT. Two patients (4%) have gotten been we used from immunosuppressants more than 2 years after LDLT 4 years prior. We examined the impact of FoxP3+CD4+CD25+ T cells both in recipients with almost daily immunosuppressants and those who acquired almost tolerance. The proportion of FoxP3+/CD4+CD25+ T cells in the almost tolerance group was significantly higher than that in the almost daily immunosuppressant group (P<.05). The increased proportion of FoxP3+/CD4+CD25+ T cells significantly correlated with time after LRLT (y=0.0964x+42.02, R2=0.8854). Repeated intraportal DST may be a goot tool to induce immunologic tolerance after LDLT. Both donor type CD56+ T cells and FoxP3+/CD4+CD25+ T cells may act as important regulatory cells for tolerance. The period after LDLT is important for acquiring immunologic tolerance.
    Transplantation Proceedings 03/2012; 44(2):560-4. · 1.00 Impact Factor
  • Article: Liver transplantation surgical techniques for extensive retroperitoneal tumor with major blood vessel involvement: a case report.
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    ABSTRACT: A case of a 71-year-old man with a huge retroperitoneal tumor situated behind the liver, which strongly compressed the liver inferior vena cava (IVC), and gastrointestinal tract is described. With the techniques of whole liver extraction and autologous orthotopic liver transplantation, we successfully removed the tumor. We have the surgical techniques, essential elements, and indications for this procedure.
    Transplantation Proceedings 03/2012; 44(2):579-80. · 1.00 Impact Factor
  • Article: Induction of elastin expression in vascular endothelial cells relates to hepatoportal sclerosis in idiopathic portal hypertension: possible link to serum anti-endothelial cell antibodies.
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    ABSTRACT: Hepatoportal sclerosis accompanied by dense elastic fibre deposition is generally regarded as the primary lesion in the development of idiopathic portal hypertension (IPH). This study was performed to clarify the mechanism of elastic fibre deposition in the peripheral portal tracts of IPH liver in relation to serum anti-endothelial cell antibodies (AECA). In-vitro experiments were performed using human dermal microvascular endothelial cells (HMVEC) and patients' sera. The presence of serum AECA was assayed by a cell-based enzyme-linked immunosorbent assay (ELISA) using HMVEC. Immunohistochemical analysis of elastin was performed using liver tissue sections of IPH patients. IPH sera contained one or more AECA that could bind to the vascular endothelial cells of the peripheral portal tracts of the liver. When the value of AECA greater than the mean ± 2 standard deviations of healthy controls was regarded as positive, the positive detection rate of either immunoglobulin (Ig)G, IgA or IgM AECA in IPH sera was 30% (10 of 33 cases). IPH sera induced the expression of elastin in HMVEC, which appeared to be associated with the presence of AECA. Apoptosis was also induced in HMVEC by the stimulation with IPH sera. In vivo, elastin expression was observed in the endothelial cells of the peripheral portal tracts of IPH livers in a proportion of cases. The disease pathogenesis of IPH seems to be heterogeneous, and this study elucidated a possible contribution of the induction of elastin expression in the portal vessels to hepatoportal sclerosis of IPH, which might be linked to serum AECA as a causative factor.
    Clinical & Experimental Immunology 03/2012; 167(3):532-42. · 3.36 Impact Factor
  • Article: Effects of (-)-Epigallocatechin Gallate on the Motility and Penetrability of Frozen-Thawed Boar Spermatozoa Incubated in the Fertilization Medium.
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    ABSTRACT: Epigallocatechin gallate (EGCG) is the major polyphenol in green tea (Camellia sinensis) and is known for its antioxidant effects. The objective of the present study was to examine the effects of EGCG during in vitro fertilization (IVF) on the sperm quality and penetrability into oocytes. In the first experiment, the effects of concentration and incubation period of EGCG on the motility and penetrability of spermatozoa were examined. When frozen-thawed spermatozoa were incubated in IVF medium supplemented with 0 (control), 1, 50 and 100 μm EGCG for 1, 3 and 5 h, supplementation with 50 and 100 μm EGCG improved motility of the spermatozoa (p < 0.05), but not viability, as compared with the control group. When frozen-thawed spermatozoa were co-incubated with in vitro-matured (IVM) oocytes in IVF medium supplemented with 50 and 100 μm EGCG for 5 h, supplementation of EGCG had positive effects on sperm penetration rates. In the second experiment, the effects of supplementation of EGCG in IVF medium on penetrability of sperm from different boars and development of fertilized oocytes were evaluated. When frozen-thawed spermatozoa from six boars were co-incubated with IVM oocytes in IVF medium supplemented with 50 μm EGCG, the effect of EGCG on sperm penetration and development of oocytes after fertilization was found to vary with individual boar. Our results indicate that motility and penetrability of boar spermatozoa are improved by co-incubation with 50 μm EGCG, but the effects vary with individual boars.
    Reproduction in Domestic Animals 02/2012; · 1.36 Impact Factor
  • Article: Development of low-energy and high-current-density ion beam system.
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    ABSTRACT: A low-energy ion beam system operating at a dc voltage of less than 300 V was developed using an ion source with a multicusp magnetic field. A high-current-density ion beam of 6.9 mA∕cm(2) was successfully extracted at the electrode. The beam extraction characteristics for flat and concave electrodes were compared. In the case of a concave electrode with a designed focal length of 350 mm, it was observed that the beam profile was sharper than that obtained using a flat electrode.
    The Review of scientific instruments 02/2012; 83(2):02B708. · 1.52 Impact Factor
  • Article: Shunting arc plasma source for pure carbon ion beam.
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    ABSTRACT: A plasma source is developed using a coaxial shunting arc plasma gun to extract a pure carbon ion beam. The pure carbon ion beam is a new type of deposition system for diamond and other carbon materials. Our plasma device generates pure carbon plasma from solid-state carbon material without using a hydrocarbon gas such as methane gas, and the plasma does not contain any hydrogen. The ion saturation current of the discharge measured by a double probe is about 0.2 mA∕mm(2) at the peak of the pulse.
    The Review of scientific instruments 02/2012; 83(2):02A510. · 1.52 Impact Factor
  • Article: Magnifying endoscopy findings in follicular lymphoma of the rectum using narrow band imaging.
    Endoscopy 01/2011; 43 Suppl 2 UCTN:E346-7. · 5.21 Impact Factor
  • Article: Salicylate induced neural changes in the primary auditory cortex of awake cats.
    X Zhang, P Yang, Y Cao, L Qin, Y Sato
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    ABSTRACT: Systemic administration of salicylate at high doses can induce reversible tinnitus and hyperacusis in humans and animals. For this reason, a number of studies have investigated the salicylate-induced changes of neural activity in the auditory cortex (AC); however, most previous studies of the AC were conducted on brain slices or anesthetized animals, which cannot completely represent the actual conditions. Few efforts have been made to examine the neural activity of awake animals, and only recorded the local field potential (LFP) of the AC. In this study, we recorded neural spike activities from chronically implanted electrodes in the primary AC (A1) of awake cats, and investigated the changes of neural responses to pure-tone and click-train stimuli after systemic injection of 200 mg/kg salicylate. We found that sound-evoked spike activities were significantly increased from 1 h after salicylate administration, and the increase of neural responses lasted longer than 3 days with a peak at 12 h. Salicylate not only increased the amplitude of transient responses at the onset and offset of pure-tone stimuli, but also induced a sustained response during the prolonged stimulus period and a late response at ∼100 ms after stimulus offset. The significant enhancement of neural responses was observed over the entire tested frequency range (0.1-16 kHz) with a relative peak in the band of 3.2-9.6 kHz. The capability of exhibiting spikes synchronizing with successive clicks was also enhanced. All these effects were more apparent when the neurons were driven by high intensity sounds. Salicylate-administration also decreased the mean spontaneous rate in A1 units, and the decrease of spontaneous rate was larger in the units with a high initial spontaneous rate. Our data confirm that salicylate can modulate the neural activity at the cortical level and provide more information for understanding the mechanism of salicylate-induced tinnitus.
    Neuroscience 10/2010; 172:232-45. · 3.38 Impact Factor
  • Article: 100 W-class solar pumped laser for sustainable magnesium-hydrogen energy cycle
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    ABSTRACT: A solar pumped laser system with 7%–9% slope efficiencies has been developed. A Fresnel lens ( 2×2 m , f=2000 mm ) is mounted on a two-axis sun tracker platform and focuses solar radiation toward laser cavity, which embraces Cr:Nd:yttrium aluminum garnet ceramic rod. The maximum emitted laser power is 80 W corresponding to maximum total area performance of 20 W / m <sup>2</sup> for the Fresnel lens area. This solar laser system would be used as a section of power plant in a magnesium energy cycle as a cost-efficient solar energy converter. Using direct solar radiation into laser, 4.3% net conversion efficiency has been achieved.
    Journal of Applied Physics 11/2008; · 2.17 Impact Factor
  • Article: Treatment with intravitreal steroid reduces blood-retinal barrier breakdown due to retinal photocoagulation.
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    ABSTRACT: The effect of corticosteroid treatment on blood-retinal barrier breakdown caused by argon-laser panretinal photocoagulation was evaluated in the rabbit eye. One day before photocoagulation, eyes were given either a sub-Tenon (20-mg) or intravitreal (2-mg) injection of triamcinolone acetonide. The severity of blood-retinal barrier breakdown was measured after photocoagulation using rapid sequential magnetic resonance imaging following intravenous administration of gadolinium diethylenetriaminepentaacetic acid. Leakage of gadolinium diethylenetriaminepentaacetic acid into the vitreous space was significantly lower in eyes that received intravitreal triamcinolone acetonide than in control eyes (P = .007); however, sub-Tenon triamcinolone acetonide produced no significant reduction in leakage (P = .65) compared with controls. Fluorescein angiography supported the magnetic resonance imaging findings. We conclude that retinal photocoagulation in the rabbit eye produces blood-retinal barrier breakdown that is partially amenable to corticosteroid treatment.
    Archives of Ophthalmology 09/1992; 110(8):1155-9. · 3.71 Impact Factor
  • Article: Blood-retinal barrier breakdown caused by diode vs argon laser endophotocoagulation.
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    ABSTRACT: We compared the effects of argon and diode laser endophotocoagulation on blood-retinal barrier breakdown using real-time magnetic resonance imaging following intravenous gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA) injection. Endophotocoagulation was performed on eyes of pigmented rabbits with either the argon or the diode laser to produce ophthalmoscopically similar lesions. Magnetic resonance imaging studies were performed either 2 or 7 days after laser treatment, and coronal T1-weighted proton images were obtained in the first 20 minutes following Gd-DTPA injection. The mean signal intensity over a region of interest in the vitreous cavity was analyzed, and an initial rate analysis was performed on each time-course curve. Two days after treatment, argon laser-treated eyes showed significantly greater leakage of Gd-DTPA than diode laser-treated eyes. The leakage in both groups was substantially reduced by posttreatment day 7. Histopathologic examination performed 2 days following photocoagulation showed less damage of the retinal pigment epithelium and more severe occlusion of the choriocapillaris and deep choroidal vessels in diode laser-treated eyes. These changes may serve to explain the observed differences in Gd-DTPA leakage.
    Archives of Ophthalmology 03/1992; 110(2):277-81. · 3.71 Impact Factor
  • Source
    Article: Blood-retinal barrier breakdown investigated by real-time magnetic resonance imaging after gadolinium-diethylenetriaminepentaacetic acid injection.
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    ABSTRACT: Recent magnetic resonance imaging (MRI) studies show that gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA) entry into the vitreous space can be used as a qualitative marker of blood-retinal barrier (BRB) disruption. To determine if a more quantitative measurement of BRB breakdown could be obtained, the utility of acquiring real-time, T1-weighted proton images was studied after Gd-DTPA injection. Two days before the MRI experiment, panretinal photocoagulation was done. The mean signal intensity over selected regions-of-interest (ROI) in the vitreous and anterior chamber was followed before and after (0, 10, 20, 30, 45, and 60 min) Gd-DTPA injection (1.0 mmol/kg, intravenously). At every laser power setting used in this study (0, 200, 400, 600, and 800 mW), the change in the mean signal intensity could be approximated by a simple exponential equation. However, the time constants determined for these curves were too imprecise to be useful as correlates between laser power and BRB breakdown. The slope of the line fit to the data in the first 20 min postinjection (ie, an initial-rate analysis) was a more precise correlate between BRB breakdown and laser power. This slope represented the rate of change in mean signal intensity in the ROI as a result of the entry of Gd-DTPA, and it was called the "leakiness" parameter. The leakiness parameter reflected changes in the permeability surface area product of the BRB if the blood flow and the Gd-DTPA arterial concentration immediately after injection were approximately the same between animals.
    Investigative Ophthalmology &amp Visual Science 11/1991; 32(11):2854-60. · 3.60 Impact Factor

Institutions

  • 2012
    • Yamanashi University
      • Interdisciplinary Graduate School of Medicine and Engineering
      Kōfu-shi, Yamanashi-ken, Japan
    • Yamaguchi University
      Yamaguchi-shi, Yamaguchi-ken, Japan
    • Niigata University
      • Division of Digestive and General Surgery
      Niigata-shi, Niigata-ken, Japan
  • 2010
    • China Medical University (PRC)
      • Department of Physiology
      Shenyang, Liaoning, China
  • 1992
    • Duke University
      • Department of Ophthalmology
      Durham, NC, USA
  • 1991
    • National Institute of Environmental Health Sciences
      Durham, NC, USA