Biomedical subjects

Kenji Kawai

Publications and source records attributed to Kenji Kawai.

27 records · Page 2Linked to original sources

PubMed2004

Comparison of 23 gauge and 25 gauge anterior capsulotomy forceps.

In cataract surgery, the most commonly-used procedure for incision of the anterior capsule is continuous curvilinear capsulorrhexis (CCC), developed by Gimbel and Neuhann. As Gimbel has reported, CCC is a safe technique for phacoemulsification and aspiration (PEA) and intraocular lens (IOL) implantation. The optimum incision method for CCC is thought to be that of using anterior capsulotomy forceps. Recently, I have developed the side-port 23 gauge anterior capsulotomy forceps (23G forceps), manufactured by Asico, which can be manipulated via a small incision, as well as the side-port 25 gauge anterior capsulotomy forceps (25G forceps) and 25/23 gauge tapered anterior capsulotomy forceps (tapered forceps), manufactured by Inami, which are thought to provide even better ease of handling. In view of the fact that the visibility, ease of handling, bending, adverse effect on the wound, and effect on the cornea of these various forceps are important, the present comparison study among these forceps was conducted on pig lenses by means of 0.1 % trypan blue staining of the anterior capsule. It was found that capsulorrhexis was difficult with the 25G forceps because of the strong bend of the shaft. However, the tapered forceps has little bend, and like the 23G forceps, it showed outstanding handling and visibility and had little adverse effect on the wound.

Animals↗

PubMed2003

Efficacy of oral vaccine against bacterial coldwater disease in ayu Plecoglossus altivelis.

The development of a practical vaccination method against bacterial coldwater disease (BCWD) in ayu Plecoglossus altivelis and the efficacy of oral administration of formalin-killed cells (FKCs) of Flavobacterium psychrophilum was investigated. The FKC was administrated at a dose of 0.1-0.2 g kg(-1) body weight to juvenile ayu (0.5 g body weight) every day for 2 wk or on 5 days over 2 wk. Experimental immersion challenge at 3 and 7 wk after vaccination showed significantly higher survival rates than the controls. The results show the effectiveness of oral vaccination against BCWD in ayu.

Administration, Oral↗

PubMed2003

Vascular networks and endothelial cells in the rat experimental pituitary glands and in the human pituitary adenomas.

There has been considerable interest in the relationship between hormone-secreting endocrine cells (HSEC) and their microvessels (MVN) in human pituitary gland. However, microcirculatory networks have rarely been studied in three dimensions (3D). Therefore, this study was designed to visualize and to reveal the relationship between hormone secreting endocrine cells and their microvessel environment including vascular endothelial cells in 3D using rat pituitary glands under various experimental conditions by confocal laser scanning microscopy (CLSM). By CLSM, the 3D distributions of MVN were visualized and revealed a relationship between HSEC and MVN in experimental pituitary glands and human pituitary adenomas. Therefore, 3D reconstructed imaging by CLSM is a useful technique with which to investigate the microvessel environment of hormone-secreting cells and has the potential to reveal dynamic hormone-secreting pathways.

Adenoma↗

PubMed2003

The correlation between various types of intraocular lens and laser wavelength.

PURPOSE: To analyze effects of the composition and the color of intraocular lenses (IOLs) on laser wavelength. DESIGN: A case control study. METHOD: Laser light rays at wavelengths ranging from 0.1 to 0.5 W were directed at a polymethymethacrylate ocular model fitted consecutively with three types of IOLs at various refractive powers. A laser detector was placed on the model beneath the lenses. The laser beam was passed through the IOLs and the output measured by a sensor. Attenuation rate was calculated. RESULTS: The colored IOL caused significantly more attenuation than did the noncolored IOLs (p <.01). A 30-diopter colored IOL showed an attenuation rate of up to 15% at a wavelength of 488 + 514 nm. CONCLUSIONS: Consideration of the wavelength and the output of a laser for a particular IOL is required when laser photocoagulation of the retina is performed in patients with pseudophakia.

Color↗

PubMed2002

Stacking of conical molecules with a fullerene apex into polar columns in crystals and liquid crystals.

Polar liquid crystalline materials can be used in optical and electronic applications, and recent interest has turned to formation strategies that exploit the shape of polar molecules and their interactions to direct molecular alignment. For example, banana-shaped molecules align their molecular bent within smectic layers, whereas conical molecules should form polar columnar assemblies. However, the flatness of the conical molecules used until now and their ability to flip have limited the success of this approach to making polar liquid crystalline materials. Here we show that the attachment of five aromatic groups to one pentagon of a C(60) fullerene molecule yields deeply conical molecules that stack into polar columnar assemblies. The stacking is driven by attractive interactions between the spherical fullerene moiety and the hollow cone formed by the five aromatic side groups of a neighbouring molecule in the same column. This packing pattern is maintained when we extend the aromatic groups by attaching flexible aliphatic chains, which yields compounds with thermotropic and lyotropic liquid crystalline properties. In contrast, the previously reported fullerene-containing liquid crystals all exhibit thermotropic properties only, and none of them contains the fullerene moiety as a functional part of its mesogen units. Our design strategy should be applicable to other molecules and yield a range of new polar liquid crystalline materials.

Journal Article↗

PubMed2002

Adherence of Flavobacterium psychrophilum on the body surface of the ayu Plecoglossus altivelis.

Bacterial cold water disease in the ayu Plecoglossus altivelis caused by Flavobacterium psychrophilum is a serious problem in the Japanese freshwater culture industry. The distribution and activity of this bacterium on the body surface of the ayu in the infection process was investigated. The survival of F. psychrophilum in tap water showed that this bacterium might sustain its infectivity for 24 h. In an experimental infection, juvenile ayu were immersed in water containing 10(8.9) CFU/ml F. psychrophilum, and the progressing infection was followed by scanning electron microscopy during a 24-h period. This bacterium was observed in the ayu for 24 h adhering to the lower jaw and caudal peduncle, where the epidermis tissue was collapsed. This study showed that bacterial suspension in water sustains the activity of this bacterium. F. psychrophilum attaches especially to the jaw and caudal peduncle, growing at these sites, collapsing the dermal structure and invading the tissues.

Animals↗

PubMed2002

The microendoscope for ciliary process photocoagulation in neovascular glaucoma.

The safety and efficacy in endoscopic ciliary body photocoagulation was evaluated in 6 patients with intractable neovascular glaucoma secondary to proliferative diabetic retinopathy. After a mean follow-up of 8 weeks, the mean intraocular pressure (IOP) decreased from 39.2 +/- 5.0 mmHg preoperatively t o 19.5 +/- 3.8 mmHg postoperatively (p < 0.05, Wilcoxon signed-ranks test). Although intense inflammation was observed as an immediate postoperative complication, fibrin, eye pain and phthisis did not develop in any of the patients.

Aged↗

PubMedDate not supplied

lambda-crystallin related to dehydroascorbate reductase in the rabbit lens.

PURPOSE: To evaluate the relationship of lambda-crystallin to reduced nicotinamide adenine dinucleotide (NADH)-dependent dehydroascorbate (DHA) reductase found specifically in the rabbit lens. METHODS: DHA reductase Fractions I-IV were separated from the lambda/betaL1-crystallin fraction of rabbit lens soluble protein by diethylaminoethyl (DEAE)-cellulose ion-exchange column chromatography, and then the enzyme was partially purified from Fraction II by rechromatography on the same ion-exchange column. The isolated DHA reductase fractions were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Western blotting, native isoelectric focusing and two-dimensional gel electrophoresis. RESULTS: Using Western blot and a probe of antiserum to recombinant lambda-crystallin, the main 33-kDa protein band was strongly stained in all the rabbit lens DHA reductase fractions, and most of the additional protein bands of approximately 25-30 kDa were also detectable. In the partially purified enzyme, the 33-kDa subunit alone was identified as a distinct protein band by SDS-PAGE, and a main basic protein was found at pI 7.6 by native isoelectric focusing. In addition, many bands of more acidic proteins were separated from other enzyme fractions, and protein spots corresponding to the 33 and/or approximately 25-30-kDa subunits were detected in each of the more acidic proteins by two-dimensional gel electrophoresis. CONCLUSION: These results suggest that lambda-crystallin is closely related to the DHA reductase in the rabbit lens. The above heterogeneity of the enzyme-crystallin may arise from posttranslational modifications.

Amino Acid Sequence↗

PubMedDate not supplied

Efficacy of combination chemotherapy for stage IV colon cancer with extensive peritoneal dissemination and multiple liver metastases: a case report.

A patient was diagnosed as having subacute ileus due to advanced cancer of the descending colon with multiple liver metastases and was treated by palliative left hemicolectomy. He was considered to have Stage IV cancer based on the finding of extensive peritoneal dissemination. Histopathological examination showed that the tumor was moderately differentiated adenocarcinoma. Postoperative palliative chemotherapy was given with 5-FU and LV twice a month as 1 course, and he received a total of 3 courses. As a result, the multiple liver metastases were completely eliminated. However, his liver metastases recurred, so CPT-11 was added to 5-FU and LV for another 3 courses. When bilateral pleural effusions developed about 1 year postoperatively, CPT-11 was changed to CDGP. Jaundice and massive ascites eventually developed, and he died about 1 year and 5 months postoperatively.

Adenocarcinoma↗