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S Arai

Publications and source records attributed to S Arai.

At least 19 recordsLinked to original sources
PubMed2006

Recent results on hydrogen and hydration in biology studied by neutron macromolecular crystallography.

Neutron diffraction provides an experimental method of directly locating hydrogen atoms in proteins, a technique complimentary to ultra-high-resolution [1, 2] X-ray diffraction. Three different types of neutron diffractometers for biological macromolecules have been constructed in Japan, France and the United States, and they have been used to determine the crystal structures of proteins up to resolution limits of 1.5-2.5 A. Results relating to hydrogen positions and hydration patterns in proteins have been obtained from these studies. Examples include the geometrical details of hydrogen bonds, H/D exchange in proteins and oligonucleotides, the role of hydrogen atoms in enzymatic activity and thermostability, and the dynamical behavior of hydration structures, all of which have been extracted from these structural results and reviewed. Other techniques, such as the growth of large single crystals, the preparation of fully deuterated proteins, the use of cryogenic techniques, and a data base of hydrogen and hydration in proteins, will be described.

Biology↗
PubMed2006

Herpes simplex virus hepatitis: expanding the spectrum of disease.

We describe 2 transplant patients with herpes simplex virus (HSV) hepatitis who were minimally symptomatic throughout their illness. The spectrum of disease caused by HSV hepatitis is more variable than previously reported in this population. HSV hepatitis should be considered in immunocompromised hosts with elevated transaminases without evidence of fulminant hepatic necrosis.

Adolescent↗
PubMed2005

A clinical study of Japanese patients with ulcer induced by low-dose aspirin and other non-steroidal anti-inflammatory drugs.

BACKGROUND: The incidence and severity of non-steroidal anti-inflammatory drugs (NSAIDs)-induced gastro-duodenal ulcer have not been extensively studied in Japan. AIM: We performed a prospective study to clarify NSAIDs-induced gastro-duodenal injury, focusing especially on low-dose aspirin (L-A). METHODS: Two hundred and thirty-eight patients with bleeding peptic ulcers admitted to our hospital. History of taking NSAIDs and anti-ulcer drugs was obtained from all patients who underwent endoscopic examinations. The lesion scores of patients taking L-A were classified numerically from zero (no lesion) to five (ulcer). RESULTS: The NSAIDs were associated with 28.2% of hemorrhagic ulcers. The rates of patients using L-A, loxoprofen, diclofenac, and combination of two of these drugs were 27, 16, 10 and 9%, respectively. Co-administered anti-ulcer drugs were cytoprotective anti-ulcer drugs (27%), H2 receptor antagonists (16%), PPI (4%), and none (53%). In patients taking L-A, H2 receptor antagonists were used most frequently. The HP was positive in 63% of L-A-induced ulcer cases and in 69% of NSAIDs other than low-dose aspirin-induced ulcer cases. The lesion scores of patients taking L-A with H2 receptor antagonists or PPI were significantly lower than those of patients who were taking only L-A (P < 0.05). CONCLUSIONS: Approximately one-third of hospitalized patients with NSAIDs-induced hemorrhagic ulcer showed an association with L-A. Prospective randomized controlled trials including H2 receptor antagonists are required to establish preventive efforts aimed at L-A-induced gastro-duodenal injury.

Adult↗
PubMed2005

[Clinical experience with aortic connector system].

From April to December 2002, 40 patients underwent coronary artery bypass grafting (CABG) using the St. Jude Medical (Minneapolis) Symmetry bypass system (aortic connector system: ACS). 59 proximal anastomoses (51 saphenous vein grafts, 8 radial artery grafts) were performed with the ACS. One saphenous vein graft occluded during operation. Postoperative evaluation of the anastomotic patency was carried out by angiography in 45 grafts. Five of the saphenous vein grafts were occluded (5/38). One patient who was shock state before operation presented with postoperative unconsciousness. Another patient died at 8th postoperative day caused by ventricular fibrillation. We conclude that the ACS produces a simple, quick way of performing the proximal anastomosis without the need for clamping the aorta, allows reducing risk of embolization by aortic manipulation. However, it is necessary to discuss sufficiently using the ACS, because the graft patency with the ACS is lower than with standard suturing technique.

Aged↗
PubMed2004

Improving tuberculosis therapy completion after jail: translation of research to practice.

Inmates have high rates of latent tuberculosis infection (LTBI), but inmates are often released early and do not complete therapy in the community. This study evaluated the translation of results from a randomized trial to improve therapy completion to usual care in a county jail using Rogers' Diffusion of Innovation theory. Inmates who received a single education in the randomized trial in 1998-1999 (study group) were compared to inmates educated by Jail Discharge Planners in 2002-2003 (usual care group). Outcomes were rates of completion of a visit to the TB clinic and completion of therapy. Subjects in the usual care group were significantly less likely to go to clinic in the 30-day period after release (relative risk 0.84, 95% confidence interval 0.75-0.95). The transfer of an educational protocol did not achieve results seen under study conditions, mostly because of implementation fidelity. The educational session in the usual care period for 81.0% of inmates took 5 min, as compared to 10-15 min during the randomized trial. Differences in personnel administering the protocol, training, high turnover and time available may also account for lower rates seen. Practical clinical trials should focus on the context of care as well as the intervention and should have participation by those who will be implementing results.

Adult↗
PubMed2004

Restoration of visual responses following transplantation of intact retinal sheets in rd mice.

PURPOSE: To correlate the functional outcomes with histologic findings following transplantation of fetal retinal sheets in rd mice, and to investigate the mechanisms of visual function restoration. METHODS: Twenty-one postnatal day 31-38 rd/rd (C3H/HeJ) mice were transplanted in one eye with retinal sheets (1.0 x 0.4 mm) obtained from embryonic day (E) 17 enhanced-green-fluorescent protein (eGFP) mice. Five mice underwent sham surgery without insertion of tissue. Four to five weeks after transplantation, visual responses to a light flash were recorded across the superior colliculus (SC) in seven eyes of seven transplanted mice that had clear corneas and lenses, and in all five sham surgery mice. Following the SC recording, the eyes were enucleated and processed for immunohistochemistry and examined using confocal microscopy. RESULTS: In three out of the seven eyes (43%), positive responses were recorded in the SC in an area topographically corresponding to the placement of the transplant in the host retina. No responses were recorded in the untreated eyes of 5-week-old and 9-week-old rd/rd mice, and in the 9-week-old sham surgery mice. In contrast, visual responses were recorded over the entire SC in normal eyes. The response onset latencies of the 3 transplanted mice with responses were similar to those of normal control mice. The organization of the graft did not appear to correlate as expected with the electrophysiology results, as eyes with well-organized, laminated grafts showed no response whereas the three light-responsive eyes had rosetted or disorganized grafts. All three light-responsive eyes demonstrated much higher levels of recoverin immunoreactivity in the host retina overlying the graft compared with untreated age-matched rd/rd mice. CONCLUSION: Restoration of the SC visual response does not appear to depend on a well-organized transplant in the rd mouse. Increased recoverin-staining in the host retina in light-responsive animals suggested that host cone rescue was the likely mechanism of vision restoration in this transplant model.

Animals↗
PubMed2004

Alternative culture conditions for isolation and expansion of retinal progenitor cells.

PURPOSE: To investigate different in vitro model systems for retinal progenitor cell (RPC) isolation and expansion. METHODS: RPCs were isolated from embryonic day (E) 17 Long Evans rat retinas. Three different culture media: (1) modified serum free defined media (2) serum-containing media and (3) embryonic stem cell (ES)-conditioned media were used for RPC isolation and long term expansion. Expression of various cellular markers and cell morphologies were compared among the three culture systems at different passages by immunostaining and confocal microscopy. RESULTS: All three culture systems could maintain RPCs as nestin-positive cells (78-87%) after long-term in vitro expansion. However, RPCs appeared to proliferate faster in the serum-free culture system. The ES-conditioned media provided the best RPC survival. Cells appeared smaller at early passages compared with later passages. This morphology change occurred at P9-P10 in the serum-free medium, and at P5-P6 in the other two culture systems. CONCLUSIONS: The serum-free medium may be superior for preventing RPC differentiation during expansion.

Animals↗
PubMed2003

[Lateral tunnel versus extracardiac cavopulmonary connections].

To examine the mid term outcome of the lateral tunnel Fontan and the result is to be compared to extracardiac Fontan operation. Between March 1991 and May 2002, 72 lateral tunnel (LT) and 28 extracardiac conduit (EC) total cavopulmonary connection (TCPC) were performed. Right atrium was incised parallel to the sulcus terminalis and LT was created by using autologous right atrial wall. Lateral tunnel size was determined 1-2 mm larger than normal half pulmonary artery (PA) size according to the body weight. There were 1 early and 1 late death, both initial LT group. Supraventricular tachycardia was found in 1 patient with EC group and 4 in LT group (all heterotaxy syndrome). There were no differences in mortality and mobidity between LT and EC TCPC. Lateral tunnel TCPC is useful especially to small infants and children.

Adolescent↗
PubMed2003

Expression of cyclooxygenase-2 in human hyperplastic gastric polyps.

Cyclooxygenase (COX)-2, an inducible isoform of prostaglandin synthetase, has been reported to be a key molecular target of colon cancer prevention by nonsteroidal anti-inflammatory drugs. Recently, it has been shown that Helicobacter pylori (H. pylori) could induce COX-2 together with inflammatory cytokines. Although human hyperplastic gastric polyps disappeared or decreased in number and size after eradication of H. pylori, the mechanisms in this step, especially the roles of COX-2, have not been yet elucidated. The aims of the present study were to examine the expression and localization of COX-2 in human hyperplastic gastric polyps immunohistochemically. Twelve specimens of human hyperplastic gastric polyps were obtained from endoscopic polypectomy. The expression of the COX-2 protein was immunohistochemically examined on formalin-fixed and paraffin-embedded tissue sections using an anti-COX-2 antibody and an avidin-biotin complex method. Cells expressing COX-2 were further immunohistochemically identified using a specific antibody against macrophages (CD68), and myofibroblasts (alpha-smooth muscle actin). Immunoreactive COX-2 was predominantly and strongly expressed in interstitial cells in the sub-epithelial layer of 10 hyperplastic polyps. Semi-quantitative analysis revealed a significant increase in COX-2 expression in interstitial cells. The staining pattern of macrophages and myofibroblasts partly corresponded to that observed for COX-2 in hyperplastic gastric polyps. These results suggest that COX-2 in mesenchymal cells induced by H. pylori may play an important role in the tumorigenesis of human hyperplastic gastric polyps.

Aged↗
PubMed2002

Effects of barley yellow mosaic disease resistant gene rym1 on the infection by strains of Barley yellow mosaic virus and Barley mild mosaic virus.

Although a Chinese landrace of barley, Mokusekko 3, is completely resistant to all strains of Barley yellow mosaic virus (BaYMV) and Barley mild mosaic virus (BaMMV), and is known to have at least two resistant genes, rym1 and rym5, only rym5 has been utilized for BaYMV resistant barley breeding in Japan. In order to clarify the effect of rym1 on BaYMV and BaMMV, and to utilize the gene for resistant barley breeding, the susceptibilities of only rym1 carrying breeding lines against BaYMV and BaMMV were investigated. In the assessment of resistance to BaYMV-I, 341 F(2) populations derived from a cross between the resistant line Y4 with only rym1 and the susceptible cv Haruna Nijo shows that the segregation loosely fits a 1R:3S ratio (0.05 > P > 0.01), suggesting that the resistance is controlled by a single recessive gene, rym1. Further, none of the F(3) lines derived from the nine resistant F(2) plants showed any disease symptoms in the field infected by BaYMV-I. The same nine F(3) lines showed almost the same agronomic characters in the field infected by BaYMV-III as those in the uninfected field, apart from the symptom of showing numerous mosaics. This result indicates that the gene rym1 has an acceptable level of resistance to BaYMV-III. In the assessment of resistance to BaYMV-II, BaMMV-Ka1 and -Na1, an artificial infection method was adopted and the susceptibilities to those viruses were investigated. Although the control varieties, Ko A and Haruna Nijo, were infected with all of them, the rym1 gene carrying BC(2)F(3) lines were completely resistant to all strains. In summary, rym1 is completely resistant to BaYMV-I, -II, BaMMV-Ka1 and -Na1, and has an acceptable level of resistance to BaYMV-III. This study concludes with a discussion of the reason why the important resistance gene rym1 was eliminated along with resistant cultivars during breeding for resistance to BaYMV.

Genes, Plant↗
PubMed2002

Global view on functional foods: Asian perspectives.

There is an old Chinese thought meaning that medicine and food are isogenic. In Japan, a national research project started to endorse the thought scientifically, with the birth of functional foods that are now known to function to reduce the risk of life-style related diseases. The science gave rise to a national policy in which some functional foods were legally approved in terms of Foods for Specified Health Use. China has also constructed a unique system for approving some functional foods. This paper pinpoints a recent trend of functional foods characteristic to Asia, with special reference to relevant topics in Japan.

Aging↗
PubMed2002

Expression of glucocorticoid receptor and 11beta hydroxysteroid dehydrogenase in a case of pulmonary epithelioid haemangioendothelioma.

This report describes a case of pulmonary epithelioid haemangioendothelioma in which the tumour cells expressed the glucocorticoid receptor and 11beta-hydroxysteroid dehydrogenase. The patient, a 15 year old girl, who had no other complaints or past illnesses, was found to have an abnormal shadow on a chest roentgenogram obtained at a school medical examination. Multiple nodular shadows in the bilateral lungs were also confirmed by computerised axial tomography scan. A diagnosis of pulmonary epithelioid haemangioendothelioma was made on the basis of lung biopsy specimens. The tumour cells were immunohistochemically positive for factor VIII related antigen, CD31, and CD34, but not surfactant apoprotein A. In addition, almost all of the tumour cells showed simultaneous expression of the glucocorticoid receptor and 11beta hydroxysteroid dehydrogenase, suggesting that steroid treatment would be effective.

11-beta-Hydroxysteroid Dehydrogenases↗
PubMed2001

anti-bis(mu-2-ammonioethanethiolato-kappa2S:S)bis[dichloropalladium(II)] dihydrate.

Each of two square-planar Pd(II) ions in the title compound, [Pd2Cl4(mu-Haet-S)2]*2H2O (Haet = 2-ammonioethanethiolate, C2H7NS), which was obtained by rearrangement of [Pd2[Pd(aet-N,S)2]4]4+ in acidic solution, is coordinated by two bridging S atoms from two Haet ligands and by two terminal Cl atoms, forming the dinuclear structure. Since the complex is situated on a center of symmetry, the two monodentate Haet arms are located on opposite sides of the central Pd2S2 square plane, i.e. the present complex is the anti isomer. The S-C-C-N torsion angle is 177.3 (6) degrees and some intermolecular hydrogen bonds are observed.

Journal Article↗
PubMed2001

Synthesis and biological activities of novel structural analogues of 2-arachidonoylglycerol, an endogenous cannabinoid receptor ligand.

Novel analogues of 2-arachidonoylglycerol (2-AG), an endogenous cannabinoid receptor ligand, were developed. Chemical synthesis of these analogues (2-AGA105 and 2-AGA109) was accomplished starting from 2-octyn-1-ol and diethyl malonate and employing Wittig coupling of triene phosphonate with an aldehyde intermediate in a convergent and stereoselective manner. These analogues should be useful lead compounds for the development of novel 2-AG mimetics.

Aldehydes↗
PubMed2001

An improved method for the rapid preparation of 2-amino-4,4a-dihydro-4a,7-dimethyl-3H-phenoxazine-3-one, a novel antitumor agent.

A simple and rapid preparation method for a novel antitumor agent, 2-amino-4,4a-dihydro-4a,7-dimethyl-3H-phenoxazine-3-one (Phx) was described. The procedure included (1) the reaction of bovine hemolysates with 2-amino-5-methylphenol, (2) one-shot denaturation of hemoglobin and proteins by methanol, and removal of the denatured hemoglobin and proteins, (3) concentration of the reaction products, and (4) purification by a Sephadex column. These procedures yielded Phx in 34% yield.

Animals↗
PubMed2001

Cloning and functional characterization of chicken p160 coactivator family members.

The factors SRC-1, TIF2 and ACTR were identified as interacting with nuclear receptors in a highly ligand-dependent manner. Because the molecular mass of each of these factors is approximately 160 kDa, they are collectively termed p160 coactivators. So far, p160 coactivators have been cloned from human, mouse and Xenopus. We report here the cloning of the chicken homologues of p160 coactivator members. As in human and mouse, chicken has three p160 coactivators. Each gene encodes an approximately 160 kDa protein which exhibits 70-80% amino acid sequence identity to human and mouse p160 coactivators. Chicken p160 coactivators also have the property of interacting with several liganded nuclear receptors. Moreover, we describe an imperfect LXXLL sequence, termed NR box 4, which is located downstream of NR box 3 and conserved between evolutionarily diverse species. The loss of NR box 4 results in a decrease of interaction with the nuclear receptor, which indicates that NR box 4 is required for efficient interaction.

Acetyltransferases↗
PubMed2001

Pulmonary carcinogenesis induced by ferric nitrilotriacetate in mice and protection from it by Brazilian propolis and artepillin C.

In experiments using the renal carcinogen ferric nitrilotriacetate (Fe-NTA) in male ddY mice, primary pulmonary cancers were also induced in bronchiolar and alveolar tissues. 4-Hydroxy-2-nonenal (4-HNE) and 8-hydroxy-2'-deoxyguanosine (8-OHdG), products of oxidative processes, increased in bronchiolar and alveolar cells after administration of Fe-NTA. These substances disappeared after oral administration of propolis or artepillin C, as shown histochemically, and correlated with an anticancer prophylactic effect of propolis and artepillin C. From our investigation, lipid peroxidation seems to play an important role in pulmonary carcinogenesis. Malignant progression from adenoma of bronchiolar or alveolar origin to malignant tumors has been proposed to involve a stepwise transformation. In our study, adenomas developed into adenocarcinomas and large cell carcinomas after treatment with Fe-NTA. In contrast, after oral administration of propolis or artepillin C, adenomas did not progress to carcinomas. Instead of developing into large cell cancers, as induced by Fe-NTA in control mice, adenomas showed remarkable proliferation of macrophages and local anti-oxidant activity after treatment with either propolis or artepillin C. Propolis and artepillin C therefore appear to inhibit lipid peroxidation and the development of pulmonary cancers.

8-Hydroxy-2'-Deoxyguanosine↗