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T Koseki

Publications and source records attributed to T Koseki.

At least 73 records · Page 4Linked to original sources
PubMed1993

Dynamic light scattering of aqueous solutions of linear aggregates induced by thermal denaturation of ovalbumin.

Dynamic light scattering measurements were performed on dilute aqueous solutions of native ovalbumin (OA) and on those of linear OA aggregates induced by thermal denaturation at low ionic strength and neutral pH. The weight-average molecular weight MW of four aggregates tested ranged from 1,700,000 to 5,500,000. The translational diffusion coefficient D0 of native OA at infinite dilution was estimated as 8.70 x 10(-7) cm2/s, which gave 56.0 A as the diameter of the rigid spherical particle. The intensity autocorrelation function of linear OA polymers was analyzed with the cumulant method to obtain the first cumulant gamma e. The dependence of gamma e on the scattering vector q at very low polymer concentration was found intermediate between those of a flexible chain and a rigid rod. The translational diffusion coefficient Dtr [identical to (gamma e/q2)q-->0] was in proportion to M-0.55W, and the magnitude was in good agreement with a value calculated from the wormlike cylinder model with values of three parameters determined in an earlier study, ML = 1600 A-1, d = 120 A, and Q = 230 A, where ML, d, and Q are the molecular weight per unit length, diameter, and persistence length, respectively. Based on these results, a new model, to be called as the dimer model, was proposed to interpret the formation mechanism of linear OA polymers induced by thermal denaturation.

Animals↗
PubMed1993

Jaw cysts with orthokeratinization: analysis of 12 cases.

The clinico-pathologic, immunohistochemical and radiological features of 12 jaw cysts with a prominent orthokeratinized epithelial lining were studied and compared with those of typical odontogenic keratocysts and dentigerous cysts. They differed significantly from odontogenic keratocysts in terms of biologic behavior and histopathologic findings. Although immunohistochemical staining of the epithelial linings for cytokeratins, EMA, CEA and involucrin has not shed any light on the histogenesis of these lesions, staining patterns for these markers were significantly different from those of odontogenic keratocysts and non-keratinized dentigerous cysts. Radiologically, nine cases appeared as dentigerous cysts; two cases, one with sebaceous differentiation, as non-dentigerous unilocular cysts, and the remaining one was exceptional as it showed multiple epidermal cysts with prominent dermal appendages histologically. It is suggested that most of the orthokeratinized jaw cysts may belong to clinico-pathological entities different from odontogenic keratocysts with the majority representing dentigerous cysts with orthokeratinization. The possibility of the existence of rare central dermoid or epidermoid cysts is also to be considered.

Adolescent↗
PubMed1993

[Isolation and characterization of oral treponemes].

The oral treponemes were isolated on nine media and classified according to Anaerobe Laboratory Manual (1977). The four media, which were used with the plate-in-bottle method, were Medium 10 (M10), M10 supplemented with 10% rumen fluid, M10 supplemented with 10% rabbit serum and cocarboxylate, and M10 added with rifampicin. The five media with the anaerobic glove box method were New Oral Spirochetes (NOS) medium, NOS medium added with rifampicin, alternated modified Oral Treponemes Isolation (aOTI) medium, and alternated M10 for anaerobic glove box. The isolation rate of the oral treponemes from 59 subgingival plaque samples of various forms of periodontal diseases was 85 percent. Ninety clinical isolates were subcultured and classified into six groups (I-VI) based on the carbohydrate fermentation and metabolic end products. Three saccaharolytic groups were further divided into nine subgroups by the fermentation patterns of sucrose, lactose, maltose and rhamnose. Two saccaharolytic subgroups were identified as Treponema socranskii, and two asaccharolytic groups were identified as "T. denticola" and "T. vincentii". However, the other subgroups and group could not be identified according to the characteristics of the presently recognized species.

Adolescent↗
PubMed1993

[Textbook of surgery by W. Schultze, used at the Tokyo Medical Academy in the early Meiji era].

Wilhelm Schultze, Professor of Surgery of the Tokyo Medical Academy, wrote "Vortraege der Allgemeine Chirurgie" for the benefit of his students in about 1880. The author examined this book and concluded that it was based upon "Lehrbuch der Chirurgie und Operationslehre" by Prof. Adolf Bardeleben, his teacher at the Charité in Berlin. Schultze's textbook was translated into Japanese and published by G. Yamazaki and U. Ishiguro, his students at the Tokyo Medical Academy, in 1884. This version was widely used as a textbook in many medical schools at that time, as well as S. Sato's translation of "Die Allgemeine Chirurgische Pathologie und Therapie" written by Prof. Theodor Billroth. The author found and introduced two different Japanese versions of Schultze's textbook printed without permission.

General Surgery↗
PubMed1992

Uveoscleral permeability to intracamerally infused ferritin in eyes of rabbits and monkeys.

The permeability of the uveoscleral outflow pathway from the anterior ocular chamber was examined in rabbit and monkey eyes using anionic ferritin as a tracer. Ferritin, infused intracamerally, had ready access to the choroidal interstitium, and the degree of penetration was generally correlated with the time and pressure relationships during infusion. In both species, there were accumulations of tracer in intercellular spaces at the lamina fusca, but tracer was also present in the sclera. Thus, in contrast to the situation in the eyes of hamsters, the uveoscleral outflow pathway in the eyes of rabbits and monkeys includes the choroidal connective tissue and allows passage of relatively large molecular weight substances.

Animals↗
PubMed1992

Purification and characterization of an antibiotic substance produced from Rhizopus oligosporus IFO 8631.

We obtained a purified antibiotic protein from the submerged cultivation broth of Rhizopus oligosporus IFO 8631 by using CM-Cellulofine chromatography and HPLC. The antibiotic did not show a broad spectrum of activity, but it was very active against some of the Bacillus species, especially against Bacillus subtillis (B. natto) at a very low concentration (less than 1 ppm). It also showed activity against other gram-positive bacteria, including Staphylococcus aureus and Streptococcus cremoris. The purified antibiotic was a simple protein of about 5,500 in molecular weight, the amino acid component being characteristically high in cystine content. This high cystine content contributed to the stability of the antibiotic over a wide pH range and against strong heating (50% of the activity remained after boiling for 1 hr).

Amino Acids↗
PubMed1992

[Ultrastructural studies of the lamina suprachoroidea in the human eye].

The lamina suprachoroidea of the human choroid was examined by electron microscopy using both thin sections and freeze fracture replicas. The lamina suprachoroidea was composed of 5-10 layers of pigmented cells interspersed with multiple layers of flattened fibroblastic cells. Tight junctions, gap junctions and intermediate junctions were seen between the fibroblastic cells. Tight junctions did not reveal zonula occludens but predominantly isolated types were revealed, as well as several pore-like fenestrations in the attenuated cell processes of the fibroblasts. The characteristic morphological appearance of the lamina suprachoroidea might suggest that the aqueous humour may be able to leak into the extraocular tissues through it. However, the numerous cellular layers and also the junctional complexes between the fibroblasts of the lamina suprachoroidea are likely to produce more resistance to uveoscleral drainage. As the multi-layered arrangement of fibroblastic cells and pigmented cells in the lamina suprachoroidea did not show the cellular barrier, it may be possible that the extraocular substances are able to flow into the eye through it.

Aged↗
PubMed1991

Role of an intrachain disulfide bond in the conformation and stability of ovalbumin.

Ovalbumin, which contains one intrachain disulfide bond and four cysteine sulfhydryls, was reduced with dithiothreitol under non-denaturing conditions, and its conformation and stability were compared with those of the disulfide-bonded form. The CD spectrum in the far-UV region revealed that the overall conformation of the reduced form is similar to that of the disulfide-bonded one. Likewise, the inaccessibility to trypsin and the non-reactivity of the four cysteine sulfhydryls, exhibited by the native disulfide-bonded ovalbumin, were still retained in the disulfide-reduced form. Thus, the reduced ovalbumin appeared to substantially take the native-like conformation. However, the near-UV CD spectrum slightly differed between the native and disulfide-reduced forms. Protein alkylation with a fluorescent dye and subsequent sequence analysis showed that the two sulfhydryls (Cys73 and Cys120) originating from the disulfide bond are highly reactive in the reduced form. Furthermore, upon proteolysis with subtilisin, the N-terminal side of Cys73 was cleaved in the reduced form, but not in the disulfide-bonded one. Upon heat denaturation, the transition temperature of the reduced form was lower, by 6.8 degrees C, than that of the disulfide-bonded one. Thus, we concluded that ovalbumin has a native-like conformation in its disulfide-reduced form, but that the local conformation of the reduced form fluctuates more than that of the disulfide-bonded one. Such local destabilization may be related to the decreased stability against heat denaturation.

Amino Acid Sequence↗
PubMed1991

[A case of Ramsey Hunt syndrome with multiple cranial nerve paralysis and acute respiratory failure].

The authors report a 56-year-old woman with Ramsey Hunt syndrome with multiple cranial nerve paralysis and acute respiratory failure. Five days before admission, she experienced right otalgia and right facial pain and consulted an otolaryngologist of our hospital, who diagnosed the illness as acute parotitis and laryngopharyngitis. One day before admission, she experienced mild dyspnea and general fatigue and came to our hospital emergency room. A chest X-ray film revealed no abnormalities but some blisters were observed around her right ear. The next day, her dyspnea became more severe and she was admitted. A chest X-ray film on admission revealed right lower lobe consolidation, and neurological examination disclosed multiple cranial nerve paralysis, i.e., paralysis of the right fifth, seventh, eighth, ninth, tenth, eleventh, twelfth and left tenth cranial nerve. The serum titer of anti-herpes zoster antibody was elevated to 1,024, and the patient was diagnosed as having Ramsey Hunt syndrome with multiple cranial nerve paralysis. Arterial blood gas analysis revealed hypoxemia with hypercapnea, which was considered to be due to aspiration pneumonia and central airway obstruction caused by vocal cord paralysis. Mechanical ventilation was soon instituted and several antibiotics and acyclovir were administered intravenously, with marked effects. Three months after admission, the patient was discharged with no sequelae except mild hoarseness. Patients with herpes zoster oticus, facial nerve paralysis and auditory symptoms are diagnosed as having Ramsey Hunt syndrome. This case was complicated by lower cranial nerve paralysis and acute respiratory failure, which is very rare.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1990

Structural analysis of potential barriers to bulk-flow exchanges between uvea and sclera in eyes of Macaque monkeys.

The uveal tract of the eyes of monkeys was examined by electron microscopy using both thin sections and freeze-fracture replicas. The ultrastructural features of the lamina fusca in the monkey resembled those previously described for rabbit. The lamina fusca was composed of numerous interleaved processes of fibroblastic and pigmented cells and contained tight junctions between fibroblastic cell processes that were predominantly discontinuous, as well as numerous fenestrations through the attenuated cell processes. There was no regional compaction of cellular processes traversing the entire uvea at the level of the ora serrata as reported previously in hamster eyes.

Animals↗
PubMed1990

Structural analysis of potential barriers to bulk-flow exchanges between uvea and sclera in eyes of rabbits.

The uveal tract of rabbit eyes was examined using transmission electron microscopy of thin sections and freeze-fracture replicas. Emphasis was placed on the organization of pigmented and fibroblastic cells near the ora serrata and more generally in the lamina fusca, since these regions were previously found to restrict ingress of tracer molecules to the choroid in hamster eyes. There were significant differences between rabbit and hamster in the disposition of the pigmented cells and fibroblastic layers, the extent and patterns of tight junctions adjoining fibroblastic cells, and the presence of vesicles or fenestrations in the attenuated fibroblastic cell processes.

Animals↗
PubMed1990

Freezing denaturation of ovalbumin at acid pH.

The effects of rapid freezing and thawing at acid pH on the physiochemical properties of ovalbumin were examined. At low pH (around 2), UV difference spectra showed microenvironmental changes around the aromatic amino acid residues; elution curves by gel permeation chromatography showed decreasing numbers of monomers after neutralization. These changes depended on the incubation temperature (between -196 and -10 degrees C) and the protein concentration (0.5-10 mg/ml), and a low concentration of ovalbumin incubated at around -40 degrees C suffered the most damage to its conformation. With freezing and then incubation at -40 degrees C, three of the four sulfhydryl groups in the ovalbumin molecule reacted with 2,2'-dithiodipyridine. The CD spectra showed these changes in the secondary structure, but they were smaller than those when guanidine hydrochloride was used for denaturation. Supercooling at -15 degrees C or freezing at -196 degrees C had little or no effect on the conformation of the ovalbumin molecule. Thus, irreversible conformational changes of ovalbumin were caused under the critical freezing condition at an acid pH. These changes arose from partial denaturation and resembled those with thermal denaturation of ovalbumin at neutral pH.

Chromatography, Gel↗
PubMed1990

[Clinical, bacteriological, and immunological examination and treatment of two Papillon-Lefevre syndrome patients].

Papillon-Lefèvre Syndrome (PLS) is a rare disease accompanied by palmo-plantar hyperkeratosis and rapidly progressive periodontal breakdown of deciduous and permanent dentition. Two unrelated female PLS patients, four and seven years old, with severe periodontal destruction were examined. Antibody titers against seven strains by the enzyme-linked immunosorbent assay (ELISA), microbial cultures from deep periodontal pockets and mouth rinse samples and immunoblotting analysis were performed. Titers against Actinobacillus actinomycetemcomitans (A.a.) were found to be high by the ELISA test. Microbial cultures of A. a. were found in high percentage and immunoblotting results against sonicated extracts of an A. a. Y4 strain had similar patterns. All deciduous teeth were extracted from the younger patient, later permanent dentition erupted uneventfully and A. a. colonies could not be detected. However, the older patient did not exhibit improvement with conventional periodontal therapy and antibiotic (minocycline/erythromycin) treatment and A. a. colonies could be consistently cultured. After a subsequent ofloxacin medication, A. a. colony detection was suppressed. Furthermore, a reduction of gingival inflammation and pocket depth were observed. Therefore, A. a. was associated as an important pathogen in the etiology of periodontal disease in these PLS patients.

Actinobacillus↗
PubMed1990

Inhibitory effect of thiols on the degradation of albumin by human spleen cathepsin D.

The degradation of native albumin by human spleen cathepsin D was inhibited by GSH, cysteine and cysteamine. The thiols existing physiologically also inhibited reduced-carboxymethylated albumin, indicating that these thiols react preferentially with the enzyme itself rather than the substrate. The inhibitions of native albumin proteolysis were dose-dependent. These effects of thiols which have not been observed in other animal cathepsin D, suggest an essential function for cathepsin D in the human spleen.

Albumins↗