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Biomedical subjects

Y Hayasaka

Publications and source records attributed to Y Hayasaka.

At least 19 recordsLinked to original sources
PubMed2005

Cyanogenic glucosides in grapevine: polymorphism, identification and developmental patterns.

Twelve grapevine (Vitis vinifera L.) cultivars were surveyed for 'cyanide potential' (i.e. the total cyanide measured in beta-glucosidase-treated crude, boiled tissue extract) in mature leaves. Two related cultivars (Carignan and Ruby Cabernet) had mean cyanide potential (equivalent to 110 mgHCNkg-1fr.wt) ca. 25-fold greater than that of the other 10 cultivars, and so the trait is polymorphic in the species. In boiled leaf extracts of Carignan and Ruby Cabernet, free cyanide constituted a negligible fraction of the total cyanide potential because beta-glucosidase treatment was required to liberate the major cyanide fraction - which is therefore bound in glucosylated cyanogenic compound(s) (or cyanogenic glucosides). In addition, cyanide was liberated from ground leaf tissue of Ruby Cabernet but not Sultana (a cultivar with low cyanide potential). Hence, the high cyanide potential in Ruby Cabernet leaves is coupled with endogenous beta-glucosidase(s) activity and this cultivar may be considered 'cyanogenic'. A method was developed to detect and identify cyanogenic glucosides using liquid chromatography combined with tandem mass spectrometry (LC-MS/MS). Two putative cyanogenic glucosides were found in extracts from leaves of Carignan and Ruby Cabernet and were identified as the epimers prunasin and sambunigrin. Cyanide potential measured at three times over the growing season in young and mature leaves, petioles, tendrils, flowers, berries, seeds and roots of Ruby Cabernet was substantially higher in the leaves compared with all other tissues. This characterisation of cyanogenic glucoside accumulation in grapevine provides a basis for gauging the involvement of the trait in interactions of the species with its pests and pathogens.

Chromatography, Liquid↗
PubMed2001

Heterozygous 17-bp deletion in the forkhead transcription factor gene, FOXL2, in a Japanese family with blepharophimosis-ptosis-epicanthus inversus syndrome.

We examined mutations in the forkhead transcription factor gene, FOXL2, in three members a Japanese family with autosomal dominant blepharophimosis-ptosis-epicanthus inversus syndrome (BPES) and in 100 healthy controls. The FOXL2 was analyzed by direct genomic sequencing. A novel 17-bp deletion at nucleotides 1092-1108 in FOXL2 was found in the three affected patients. No mutation was found in any of the 100 healthy controls. The 17-bp deletion in FOXL2 may be involved in the pathogenesis of BPES in Japanese patients.

Adult↗
PubMed2001

Quantitative analysis of polymeric procyanidins (Tannins) from grape (Vitis vinifera) seeds by reverse phase high-performance liquid chromatography.

A reverse phase C(18) HPLC method with potential for high automated throughput has been developed for the quantitative analysis of polymeric procyanidins (tannins) in grape seed extracts. Chromatography gave rise to 13 distinct UV-absorbing peaks with good baseline separation. The UV-absorbing peak eluting last is distinct and therefore easily quantified. Biochemical analyses including ultrafiltration, protein precipitation, and Sephadex LH20 chromatography combined with electrospray mass spectrometric analyses establish that this peak predominantly contains polymeric procyanidins. The polymers, which appear to be galloylated to various degrees and seem to fragment in a characteristic manner during electrospray mass spectrometry, are well separated from catechins and procyanidin oligomers of up to 4 units. The recovery of polymeric grape seed tannins with this HPLC method was 86%, which is similar to the 89% recovery achieved with commercial quebracho tannins. The concentration of tannins in seeds from ripe Vitis vinifera cv. Shiraz grapes ranged from 1360 to 2830 mg/kg of berries.

Antioxidants↗
PubMed2001

Use of electrospray mass spectrometry for mass determination of grape (Vitis vinifera) juice pathogenesis-related proteins: a potential tool for varietal differentiation.

Methods based on liquid chromatography-mass spectrometry (LC-MS) and protein trap mass spectrometry (trap-MS) were developed to determine the complement of pathogenesis-related (PR) proteins in grape juice. Trap-MS was superior to LC-MS in terms of simplicity, rapidity, and sensitivity. Proteins with a wide range of masses (13--33 kDa) were found in the juices of 19 different varieties of grape (Vitis vinifera) and were identified as mostly PR-5 type (thaumatin-like) and PR-3 type (chitinases) proteins. Although the PR proteins in juices of grapes are highly conserved, small consistent differences in molecular masses were noted when otherwise identical proteins were compared from different varieties. These differences persisted through different harvest years and in fruits grown in different Australian locations. With the definition of four different masses for PR-5 proteins (range = 21,239--21,272 Da) and nine different masses of PR-3 proteins (range = 25,330--25,631 Da) and using statistical analysis, the methods developed could be used for varietal differentiation of grapes grown in several South Australian locations on the basis of the PR protein composition of the juice. It remains to be seen whether this technology can be extended to grapes grown worldwide and to wine and other fruit-derived products to assist with label integrity to the benefit of consumers.

Beverages↗
PubMed2001

Composition of grape skin proanthocyanidins at different stages of berry development.

The composition of grape (Vitis vinifera L. cv. Shiraz) skin proanthocyanidins has been determined at different stages of berry development. Beginning approximately 3 weeks after fruit set and concluding at commercial ripeness, the composition of isolated skin proanthocyanidins was determined using the following analytical techniques: elemental analysis, UV-Vis absorption spectroscopy, reversed-phase HPLC after acid-catalysis in the presence of excess phloroglucinol, gel permeation chromatography, electrospray ionization mass spectrometry (ESI-MS), and (13)C NMR. On the basis of these analyses, berry development was correlated with an increase in proanthocyanidin mean degree of polymerization, an increase in the proportion of (-)-epigallocatechin extension subunits, and increases in the level of anthocyanins associated with the proanthocyanidin fraction. Additionally, data acquired from ESI-MS of the isolates following acid-catalysis in the presence of excess phloroglucinol is consistent with pectin-bound proanthocyanidins.

Anthocyanins↗
PubMed2001

Isolation and structures of oligomeric wine pigments by bisulfite-mediated ion-exchange chromatography.

Methods have been developed that are based on cation exchange chromatography in the absence and presence of excess bisulfite for the isolation of wine pigments from Australian red wine and grape marc extract. The pigments were identified using HPLC and electrospray ionization mass spectrometry. The mass spectral data indicate that these pigments are C4-substituted anthocyanins with a tetracyclic structure. The pigments form a series of closely related oligomeric pigments which include those previously described in the literature, such as pigment A and vitisin A, as well as some newly identified pigments.

Chromatography, Ion Exchange↗
PubMed2001

Ocular changes after intravitreal injection of methanol, formaldehyde, or formate in rabbits.

We evaluated the effects of intravitreal injection of methanol, formaldehyde, or formate on rabbit eyes. One hundred microl of 1% methanol, 1% or 0.1% formaldehyde, or 1% formate was injected in the vitreous cavity of the right eyes of rabbits. The eyes were examined by biomicroscopy and ophthalmoscopy weekly. One month after injection, the eyes were enucleated and examined histologically. One week after treatment the animals that received 0.1% formaldehyde showed retinal vessel dilation, and the rabbits that received 1% formaldehyde showed mild posterior subcapsular cataract and retinal vessel dilation and haemorrhages. One month after treatment, the animals that received 0.1% or 1% formaldehyde developed mild posterior subcapsular cataract and retinal lesions. Animals that received 1% methanol or 1% formate showed nearly normal optical media and fundi. Histologically disorganized retina and optic nerve were seen in eyes that received 0.1% or 1% formaldehyde. Eyes that received 1% methanol or 1% formate appeared histologically normal. Our findings indicate that intravitreal injection of formaldehyde causes retinal and optic nerve damage, while methanol and formate are not or less toxic to ocular tissues.

Animals↗
PubMed2001

Effects of traditional Sino-Japanese herbal medicines on aqueous flare elevation after small-incision cataract surgery.

We evaluated prospectively the effects of traditional Sino-Japanese herbal medicines on elevation of aqueous flare. Fifty-four patients with age-related cataract undergoing phacoemulsification with intraocular lens implantation were studied. In the control group, 20 patients received no herbal medicine. In the treated groups, 14 patients were given Orengedoku- to (Huanglian-Jie-Du-Tang in Chinese) granules (7.5 g daily), 10 patients were given Kakkon-to (Ge-Gen-Tang in Chinese) granules (7.5 g daily), and 10 patients were given Sairei-to (Cai-Ling-Tang in Chinese) granules (9.0 g daily), for 3 days before surgery, the day of surgery, and for 7 days after surgery. Aqueous flare was measured before and after surgery. The differences in preoperative flare intensities among the four groups were not significant. In the control group, the flare was 29.4 photon counts/msec on day 1, and then gradually decreased. The flare intensities on days 1, 3, and 5 in the Orengedoku-to and Kakkon-to groups were significantly lower than in the control group. The flare intensities in the Sairei-to group were the same as those of the controls. Oral administration of Orengedoku-to and Kakkon-to decreased aqueous flare elevation after small-incision cataract surgery. Sairei-to had no effect on the elevation.

Administration, Oral↗
PubMed2001

Effects of Orengedoku-to and Senkanmeimoku-to, traditional herbal medicines, on the experimental elevation of aqueous flare in pigmented rabbits.

We investigated the effects of Orengedoku-to (Huanglian-Jie-Du-Tang in Chinese) and Senkanmeimoku-to (Xygan-Ming-Mu-Tang in Chinese), traditional herbal medicines, on experimantal elevation of aqueous flare in pigmented rabbits. To produce the elevation of aqueous flare in rabbits, prostaglandin E2 (PGE2) was applied to the cornea with use of a glass cylinder, or lipopolysaccharides (LPS) were injected into the ear vein. Animals were pretreated by the oral administration of 150 g/day of food containing 0.7%, 0.2% or 0.07% (w/w) Orengedoku-to, or 2%, 0.6% or 0.2% (w/w) Senkanmeimoku-to for 5 days. Aqueous flare was measured with a laser flare-cell meter. Pretreatment with 0.7% or 0.2% Orengedoku-to and 2% Senkanmeimoku-to did suppress significantly (P < 0.05) elevation of aqueous flare induced by PGE2. Pretreatment with 0.7% or 0.2% Orengedoku-to and 2% or 0.6% Senkanmeimoku-to significantly suppressed (P < 0.001) elevation of aqueous flare induced by LPS. It is possible that Orengedoku-to and Senkanmeimoku-to may migrate some forms of uveitis.

Animals↗
PubMed2000

Thaumatin-like proteins and chitinases, the haze-forming proteins of wine, accumulate during ripening of grape (Vitis vinifera) berries and drought stress does not affect the final levels per berry at maturity.

Thaumatin-like proteins and chitinases, which are pathogenesis-related (PR) proteins, were the major soluble protein components of grapes from five cultivars of Vitis vinifera. This dominance of PR proteins was apparent at berry softening (véraison) and then throughout berry development for the Muscat of Alexandria, Sultana, and Shiraz cultivars and in the berries of the Sauvignon Blanc and Pinot Noir cultivars examined at commercial maturity. The M(r) of the major thaumatin-like protein from Muscat of Alexandria grapes was 21 272, and those of the three major chitinases from this cultivar, ChitB, ChitC, and ChitD, were 25 588, 25 410, and 25 457, respectively. The vines in the study were irrigated and showed no obvious signs of disease. Shiraz vines that had not been irrigated throughout the season were clearly water stressed, but had levels of PR proteins in the berry similar to vines that had been fully irrigated. It appears that the production of PR proteins that cause protein instability in wines by grapes may be little influenced by environmental conditions.

Chitinases↗
PubMed2000

The cutler-beard bridge flap technique with use of donor sclera for upper eyelid reconstruction.

We evaluated the Cutler-Beard bridge flap technique with the use of donor sclera for upper eyelid reconstruction. The right upper eyelid of a 22-year-old man (case 1) was bitten by a dog. A mass in the left upper eyelid of an 85-year-old man (case 2) was excised. Major full-thickness defects of the eyelid with small loss of tarsus were reconstructed with the use of donor sclera. Good cosmetic results were obtained. Major full-thickness defects of the upper eyelid with small loss of tarsus may be effectively reconstructed by the Cutler-Beard technique with use of donor sclera.

Adult↗
PubMed1999

Pseudophakic cystoid macular edema treated with high-dose intravenous methylprednisolone.

PURPOSE: To evaluate the efficacy of high-dose methylprednisolone in the treatment of pseudophakic cystoid macular edema (CME). SETTING: University-affiliated hospital. METHODS: Four patients with pseudophakic CME who reported decreased visual acuities were treated with oral prednisolone (20 mg daily for 5 days), oral acetazolamide (500 mg daily for 5 days), and topical dexamethasone 0.1% and diclofenac 0.1% (4 times a day for 14 days). The CME did not resolve. Next, they were treated with high-dose (1000 mg daily) intravenous methylprednisolone for 3 days. RESULTS: In 3 of 4 eyes, the CME resolved and visual acuity improved. CONCLUSION: High-dose methylprednisolone may be effective in the treatment of pseudophakic CME.

Aged↗
PubMed1999

Analysis of diacetyl in wine using solid-phase microextraction combined with gas chromatography-mass spectrometry.

Analytical difficulties in the rapid and accurate determination of diacetyl (DA), an important flavor compound in wine, at low concentrations have been overcome by the use of solid-phase microextraction (SPME) with deuterated diacetyl-d(6) (d6-DA) as an internal standard followed by gas chromatography-mass spectrometry (GC-MS). The GC-MS analyses showed that the values of the ion response ratio of DA to d6-DA were consistent regardless of the conditions of SPME headspace and were not influenced by the presence of sulfur dioxide in wine. The quantitation value of DA was represented as the concentration of free plus bound with sulfur dioxide forms of DA. The detection limit of DA in wine was as low as 0.01 microg/mL with linearity through to 10 microg/mL.

Diacetyl↗
PubMed1999

1147 del A mutation in the arrestin gene in Japanese patients with Oguchi disease.

We examined the sequence of the arrestin gene in two unrelated patients with Oguchi disease. A 35-year-old woman and a 72-year-old man underwent a complete ophthalmological examination, including evaluation of visual acuity and color vision, fundus examination, and electroretinography. A golden-yellow discoloration was observed in their fundi. After 30 minutes of dark adaptation, the discoloration in the fundus disappeared. A deletion of an adenine in codon 309 of exon 11 of the arrestin gene was identified in both patients. Mutations in the arrestin are common in Japanese patients with Oguchi disease.

Adult↗
PubMed1999

An intrinsic DNA curvature found in the cyanobacterium Microcystis aeruginosa K-81 affects the promoter activity of rpoD1 encoding a principal sigma factor.

The rpoD1 gene in the unicellular cyanobacterium Microcystis aeruginosa K-81 encodes a principal sigma factor of RNA polymerase and is transcribed under light and dark conditions to produce multiple monocistronic transcripts. In the 5'-upstream region from rpoD1 Promoter 2, which has a sequence of Escherichia coli type, we found a sequence-directed DNA curvature with an AT-rich sequence. Insertions of 2 to 21 base pairs introduced into the curved center changed a gross geometry of the original curved DNA structure. The rpoD1 promoter activities assayed in vivo by using transcriptional lacZ fusions were correlated with the change in the gross geometry in not only a cyanobacterium but also E. coli. In addition, RNA polymerase binding to the rpoD1 promoter region and the efficiency of the mRNA synthesis from the rpoD1 Promoter 2 were also affected in vitro by the change in the geometry. These results suggest that the tertiary structure of the curved DNA is important for the rpoD1 transcription. The deletion of the center region of the curvature resulted in a considerable reduction of the transcription from Promoter 2 in the cyanobacterium. This report demonstrates that a curved DNA plays a significant role in transcription in cyanobacteria, and that this functional curvature is located in the 5'-upstream region from the rpoD gene, which encodes a principal sigma factor in eubacteria.

Bacterial Proteins↗