Synthesis of poly(methyl urethane) acrylate oligomer using 2-isocyanatoethyl methacrylate for UV curable coating

The poly(methyl urethane) acrylate oligomer was obtained by the reaction of methyl acrylate oligomer and 2-isocyanatoethyl methacrylate. Synthesis of poly(methyl urethane) acrylate oligomer was done with 2-mercaptoethanol (2-MEOH), methyl acrylate, 2,2'-azobisisobutyronitrile (AIBN, initiator) and dibutyltin dilaurate as a catalyst. Then 2-MEOH was used for functional chain transfer agent. The structure and property of the synthesized oligomers were characterized by FT-IR, FT-NMR, rheometer, and DSC. In this study, by synthetic method including the addition of 2-isocyanatoethyl methacrylate, thermal behavior of synthesized material was improved more than that reported in the previous study. Poly(methyl urethane) oligomer can be used for UV curable coatings, inks and adhesives. UV curable coating have high resistance against weather, ozone, aging, frictional wear, and heat. Besides they can absorb the shock and resist rust according to the thickness of film. It is used as an adhesive, paint, optical fiber coating agent, and waterproof agent because of these advantages at the present time.

Mapping of the interaction domain of the protein kinase CKII beta subunit with target proteins

Protein kinase CKII is composed of two catalytic (alpha or alpha') subunits and two regulatory (beta) subunits. The CKIIbeta subunit is thought to mediate the tetramer formation and interact with other target proteins. Previously we have shown that CKIIbeta interacts with ribosomal proteins L5 and L41, DNA topoisomerase IIbeta, and SAG/CKBBP1. In this study, the two-hybrid system was used to define the subregions of CKIIbeta that are involved in the interaction with L5, L41, topoisomerase IIbeta, SAG/CKBBP1, and unknown proteins, CKBBP2 and CKBBP3. The results indicated that the region between residues 1 and 167 of CKIIbeta is common binding site for L5, topoisomerase IIbeta, SAG/CKBBP1, and L41. The region between amino acids 19 and 167 of CKIIbeta is sufficient for the interaction with CKBBP3. The region between residues 67 and 130 of CKIIbeta is a minimal fragment that is required for interaction with CKBBP2. Overlay experiments showed that the region between residues 1 and 167 of CKIIbeta interacts with L5, L41, and SAG/CKBBP1 in vitro. These results suggest that the binding sites of CKIIbeta for these target proteins are not located within a small linear sequence stretch, but rather are created by a three-dimensional structure.

Neoplastic transformation and tumorigenesis associated with overexpression of phospholipase D isozymes in cultured murine fibroblasts

Phospholipase D (PLD) has been suggested to play an important role in a variety of cellular functions. PLD activity has been shown to be significantly elevated in many tumours and transformed cells, suggesting the possibility that PLD might be involved in tumorigenesis. In this study, we have established stable cell lines overexpressing PLD1 and PLD2 from fibroblast cells. These cells, but not control cells, showed altered growth properties and anchorage-independent growth in soft agar. Both PLD1 and PLD2 also induced an up-regulation of the activity of matrix metalloprotease-9 as detected by zymograms. Furthermore, both PLD1 and PLD2 transformants, but not vector-transfectants, induced undifferentiated sarcoma when transplanted into nude mice. Both PLD1- and PLD2-mediated cell cycle distributions in stable cell lines revealed an increased fraction of cells in the S phase compared with control cells. Interestingly, the level of cyclin D3 protein, known as an activator of G(1) to S phase transition in the cell cycle, was aberrantly high in cells overexpressing PLD1 and PLD2 compared with control cells. These results suggest that overexpression of PLD isozymes may play an important role in neoplastic transformation.

Expression and regulation of phospholipase D during neuronal differentiation of PC12 cells

To assess a possible role for phospholipase D (PLD) in PC12 cell signal transduction and differentiation, we have investigated the expression of PLD in PC12 cells and found that the differentiation factor, nerve growth factor (NGF) increased PLD1 protein expression and phorbol 12-myristate 13 acetate (PMA)-induced PLD activity. During neuronal differentiation, this effect showed correlation to the protein expression levels of classical protein kinase C (PKC) isozymes, PKC-alpha and -beta II, but there was no significant increase in the protein level of RhoA, another regulatory factor for PLD activation. Interestingly, PLD1 was associated with PKC-alpha or beta II, and its association gradually increased as NGF-induced neuronal differentiation progressed. PKC inhibitor, Ro-31-8220, caused a significant inhibition of neurite outgrowth and PLD activity. Furthermore, PLD1 was constitutively associated with the Shc adaptor molecule, the overexpression of which is known to induce PLD activity and to induce neurite outgrowth. Taken together, the data in this study suggests that PLD1 is closely implicated in neuronal differentiation of PC12 cells.

A case of successful primary coronary intervention for the total occlusion of left main stem with the aid of abciximab

A 61-yr-old male patient presented with severe chest pain with cardiogenic shock due to an extensive anterolateral myocardial infarction. Two-dimensional echocardiogram showed severe left ventricular systolic dysfunction (ejection fraction=17%). Emergent coronary angiogram obtained immediately after placing temporary pacing electrode revealed total thrombotic occlusion in the left main stem. We performed direct coronary intervention using kissing balloon technique with the aid of Abciximab (ReoPro) infusion. Residual stenosis with thrombus remained even after high pressure balloon dilatations, therefore we placed two stents, one in the ostia of left anterior descending (LAD) and the other in left circumflex artery (LCX). Coronary angiogram after kissing stents showed improved LAD and LCX flows without residual stenosis. Chest pain resolved and blood pressure normalized after coronary intervention. The whole procedure time was 15 min. Follow-up coronary angiogram taken one week later showed patent previous stented arteries, and echocardiography demonstrated 40% of left ventricular ejection fraction. The clinical course for one-year follow-up was uneventful.

Differential tyrosine phosphorylation of phospholipase D isozymes by hydrogen peroxide and the epidermal growth factor in A431 epidermoid carcinoma cells

The regulatory mechanism through which the phospholipase D (PLD) isoforms PLD1 and PLD2 are activated is poorly understood. We investigated the possibility that the PLD isozymes are differentially regulated in response to pharmacologic stimulants in cells. In this report, we demonstrate for the first time that H2O2 and EGF differentially induce tyrosine phosphorylation of the PLD isozymes in A431 cells, which express both PLD1 and PLD2. H2O2 induced tyrosine phosphorylation of PLD1 and PLD2, whereas EGF only caused the tyrosine phosphorylation of PLD2. Both agents also induced phosphorylation of the EGF receptor. Interestingly, the PLD isozymes were associated with the EGF receptor and PKC-alpha in a ligand independent manner. Activation of PLD by H2O2 and EGF nearly correlated with tyrosine phosphorylation of the protein in PLD1 immune complexes. Activation of PLD by both agents was inhibited by the PKC inhibitor, Ro 31-8220, and by the down-regulation of PKC. Pretreatment of the cells with the tyrosine kinase inhibitor tyrphostin AG1478 resulted in inhibition of the H2O2 and EGF-induced tyrosine phosphorylation and PLD activation. These results indicate that H2O2 and EGF induce differential tyrosine phosphorylation of PLD isozymes. Also, the activation of PLD by these agonists involves tyrosine phosphorylation and PKC activation.

Altered expression of phospholipase D1 in spontaneously hypertensive rats

To clarify the involvement of phospholipase D (PLD) in the mechanism underlying genetically-induced hypertension, we investigated the activity and expression levels of PLD in tissues taken from spontaneously hypertensive rats (SHR), and their normotensive controls, Wistar-Kyoto rats (WKY). The ADP-ribosylation factor 3 (ARF3)-dependent PLD activity and protein levels of PLD1 from SHR increased significantly in the brain and liver, but not in the heart and kidney, compared to those of WKY. The activity and expression of PLD were the same between the homogenated whole kidneys of the two strains; however, there were topographical differences in the expression and activity of PLD between the kidneys of the two strains. The activity and expression level of PLD gradually increased from the cortex to the inner medulla of WKY. The enzyme activity, and amount of PLD in the inner stripe of the outer medulla and in the inner medulla, was significantly lower in SHR than in WKY. Taken together, these results suggest that the distinctly distributed patterns of PLD in the kidney may be associated with differential signal transduction pathways that are involved in hypertension in conjunction with an increase of PLD activity in the brain and liver.

Huge calcified aneurysm of the sinus of Valsalva

Aneurysms of the sinus of Valsalva often remain undiagnosed until they rupture. A 61-year-old man had a huge, heavily calcified unruptured aneurysm, originating from the right sinus of Valsalva, detected incidentally on a chest radiograph taken for the diagnosis of cardiomegaly. Two-dimensional echocardiography revealed pericardial effusion with a huge calcified mass compressing the right ventricular outflow tract. The Doppler color-flow echocardiogram showed blood flow from the aortic root into the aneurysm. A chest computed tomographic scan revealed a large thrombosed aneurysm originating from the aortic root and measuring 10x10 cm. After pericardiocentesis, cardiac catheterization was performed, which showed that the right ventricular systolic pressure had elevated to 80 mmHg. Aortic root aortography demonstrated a huge unruptured calcified aneurysm in the sinus of Valsalva arising from the right coronary sinus. The patient underwent surgical correction to prevent aneurysmal rupture and to relieve the right ventricular outflow obstruction.

Aroma extract dilution analysis of a beeflike process flavor from extruded enzyme-hydrolyzed soybean protein

Aroma-active compounds from a beeflike process flavor, produced by extrusion of enzyme-hydrolyzed vegetable protein (E-HVP), were analyzed using aroma extract dilution analysis. The number of aroma-active compounds and the aroma intensity were increased by the addition of aroma precursors prior to extrusion. The most intense compound was 2-methyl-3-furanthiol having a cooked rice/vitamin-like/meaty aroma note. Several sulfur-containing furans, such as 2-methyl-3-(methylthio)furan, 2-methyl-3-(methyldithio)furan, and bis(2-methylfuryl)disulfide, were detected with high flavor dilution (FD) factors. Some pyrazines, such as 2-ethyl-3,5-dimethylpyrazine, 2,6-diethylpyrazine, and 3,5-diethyl-2-methylpyrazine, also had high FD factors. It is hypothesized that sulfur-containing amino acids and thiamin were important precursors in aroma formation in process flavor from E-HVP.

The relationship between gelatinase A activity in aqueous humor and glaucoma

PURPOSE

To investigate whether abnormal expression of gelatinase A in aqueous humor may be related to the development of glaucoma, the activity of gelatinase A in aqueous humor of patients with glaucoma and patients with cataract was measured and compared.

METHODS

Six primary patients with open-angle glaucoma (POAG), four patients with chronic angle closure glaucoma (CACG), four patients with normal tension glaucoma (NTG), and 14 patients with cataract were enrolled. The aqueous humor of each patient was collected during surgery, and total protein concentration and gelatinase activity in the aqueous humor were measured by protein assay kit and zymography, respectively.

RESULTS

In patients with POAG, total protein concentration doubled and gelatinase A activity increased by 3.9 times compared with patients with cataract. However, there were no statistically significant differences in total protein concentration and gelatinase A activity in patients with CACG or NTG compared with patients with cataract.

CONCLUSION

The development of POAG may be associated with the abnormal expression of gelatinase A in aqueous humor.

TIGR gene in primary open-angle glaucoma and steroid-induced glaucoma

To identify TIGR gene mutation in two Korean pedigrees of primary open-angle glaucoma (POAG), and in 25 steroid-induced glaucoma patients, TIGR gene assay was performed. Genomic DNA was extracted from peripheral blood and the TIGR gene was amplified by polymerase chain reaction (PCR). The PCR amplification products were evaluated by single-stranded conformation polymorphism and direct DNA sequencing. In POAG families, not only those patients clinically diagnosed as glaucoma, but also most of their siblings, in whom glaucoma had not yet been detected, had a proline-to-serine (TCC-to-CCC) mutation in codon 334. However, no steroid-induced glaucoma patients showed TIGR gene mutation. TIGR gene mutation, in familial POAG, was found in a different codon from that previously reported. The TIGR gene does not, however, seem to be related to steroid-induced glaucoma.

Effect of glutathione, catechin, and epicatechin on the survival of Drosophila melanogaster under paraquat treatment

The biological effect of antioxidants which showed high superoxide-scavenging (SOS) activity in an in vitro analysis was examined by using Drosophila melanogaster. When the flies were exposed to paraquat as an endogenous source of the superoxide anion, their survival rapidly decreased. Although the SOS antioxidants did not have a preventive effect against paraquat toxicity, a supplement of each SOS antioxidants as glutathione, (+)-catechin and/or (-)-epicatechin to the diet had a reparative effect on flies damaged by the superoxide anion. The survival ratio of flies fed on a diet enriched with SOS antioxidants ranged from 77% to 87%, while that of the control group was 56%. When flies were exposed to paraquat in the presence of hydrogen peroxide or iron, each combination was more toxic than paraquat alone, since the two compounds could accelerate the generation of reactive oxygen species in vivo. The SOS antioxidants, however, allowed the flies to resist the combined toxicity of paraquat and ferrous iron.

Intraocular pressure after a two-week washout following long-term timolol or levobunolol

The effect on intraocular pressure (IOP) of a 2-week washout following long-term ocular therapy with topical levobunolol or timolol for an average period of 30 months was investigated in 20 patients (11 whites and 9 blacks) with early primary open-angle glaucoma or ocular hypertensive glaucoma suspect status. The 2-week washout IOP was significantly lower than the pretreatment baseline IOP in the total 20 patients (P < 0.001), and in the 9 black patients (P = 0.004), but not in the 11 white patients (P = 0.065). However, the washout IOP was found to be significantly lower than the baseline IOP in the 5 whites with brown irides (P = 0.024) but not in the 6 whites with blue irides (P = 0.574). Thus, the 2-week washout following long-term ocular therapy with a topical beta 1-, beta 2-blocker appears insufficient to restore IOP to the pretreatment baseline level in blacks and in the whites with brown irides, whereas it may be adequate in the majority of the whites with blue irides.

Repetitive low-dose tissue plasminogen activator for the clearance of experimental vitreous hemorrhage

Our previous experimental work with tissue plasminogen activator (TPA) suggested the possibility of the clearance of vitreous hemorrhage by repetitive injections of low-dose TPA. We therefore investigated in rabbits the effect of both repeated injections of TPA and the change of the integrity of the vitreous body on the clearance of vitreous hemorrhage. Vitreous hemorrhage was produced by intravitreal injection of 0.05 ml of autologous whole blood in the pigmented rabbit eyes with intact vitreous or gas-compressed vitreous. Three intravitreal injections of 3-g TPA (total dose of 9 micrograms), separated by 7-day intervals, were performed. The endpoint for vitreous hemorrhage clearance was defined as clear visualization of the posterior central retina of the rabbits. Regardless of whether gas compression vitrectomy was performed, repeated injections of low-dose TPA resulted in rapid clearance of fresh vitreous hemorrhage in approximately two to three weeks after the last TPA injection. No evidence of retinal toxicity was seen in all experimental groups. Repetitive injections of low-dose TPA may be effective in the treatment of fresh vitreous hemorrhage.

The incidence of congenital color deficiency among Koreans

It is important to investigate the incidence of congenital color deficiency and to determine the type and degree because the color deficiency can effect as a handicap to certain occupations. The incidence of congenital color deficiency is remarkably constant among Caucasians but other races show considerable variations. We investigated the incidence of congenital color deficiency among Koreans by the use of H-R-R pseudoisochromatic plates. The present study revealed that the incidence of congenital color deficiency among Koreans was 31.5% (5.90% in men, 0.44% in women).

Bilateral effects of long-term monocular timolol therapy

We studied the bilateral intraocular pressure lowering effect of long-term unilateral timolol maleate 0.5% in 30 patients in whom early primary open-angle glaucoma had recently been diagnosed. A significant intraocular pressure reduction was found in the untreated fellow eyes (21.9 mm Hg from 26.4 mm Hg at baseline) (P less than .001), as well as in the treated eyes (21.0 mm Hg from 28.5 mm Hg at baseline) (P less than .001). Fourteen patients (47%) showed a significant bilateral intraocular pressure reduction (P less than .001), with little difference between the treated (8.2 mm Hg) and the untreated eyes (7.7 mm Hg) (P greater than .8).

Arthroplasty using the Charnley prosthesis in old tuberculosis of the hip. Clinical experience with 8-10-year follow-up evaluation

Twenty patients with tuberculosis of the hip joint were treated by low-friction arthroplasty (LFA) and followed for eight to ten years. Five of the patients had reactivation of the infection and subsequent failure despite the use of chemotherapy. Successful revision arthroplasties have been performed on two of the five hips. LFA can be recommended for patients with old tuberculous hips, provided it is combined with adequate chemotherapy both before and after surgery.