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Biomedical subjects

T Kitagawa

Publications and source records attributed to T Kitagawa.

At least 73 records · Page 4Linked to original sources
PubMed2000

Taste preferences and feeding behaviour in children with phenylketonuria on a semisynthetic diet.

UNLABELLED: Low-phenylalanine formula for phenylketonuria (PKU) made from free amino acids as a protein source (AAM formula) has a poor taste and smell. We developed a more palatable formula using low-phenylalanine peptide (LPP) as a protein source. Palatability tests performed by 41 healthy adults confirmed that the palatability of LPP formula was significantly better than that of AAM formula. A group of 48 patients with PKU who had been administered AAM formula since the newborn period were assessed for their preference between the AAM and LPP formulae and their feeding behaviour was compared to that in healthy children. Of patients, 90.9% and 66.6% of healthy infants less than 18 months of age took both formulae without apparent preference, suggesting that sensitivity to taste and smell is more immature in infancy than in later life. Of patients with PKU aged between 18 months and 11 years, 29.1% liked AAM formula rather than the LPP formula, while 66.7% took both formulae without apparent preference. Most healthy children in the same age group who had never previously tasted therapeutic formulae disliked it, although they tended to prefer the LPP formula. Of patients aged between 11 and 17 years, 84.6% preferred the LPP formula while 15.4% preferred the AAM formula. In the controls of this age group, 33% disliked therapeutic formulae, but they tended to prefer the LPP formula. CONCLUSION: In some young children with phenylketonuria the characteristic taste of amino acid mixture formula encountered in early life is considered to be imprinted and remains as a preference for a long time. Since school children with phenylketonuria usually obtain about 50% of their energy intake from natural food containing small amounts of protein, these patients are considered to have come to have similar preferences as healthy people which result from a waning of the imprinted taste of amino acid mixture formula.

Adolescent↗
PubMed2000

A genetic linkage map of the MSM Japanese wild mouse strain with restriction landmark genomic scanning (RLGS).

A high-resolution genetic map of the Mus musculus molossinus (MSM) Japanese wild mouse strain was constructed with restriction landmark genomic scanning (RLGS) and compared with that of the laboratory strain C3H. MSM is phylogenetically 1 million years apart from common laboratory mouse strains and is distinctly resistant to chemical carcinogenesis. Since it exhibits frequent genetic polymorphisms with laboratory mice but can still be easily crossed with laboratory strains, hybrids between MSM and carcinogen-sensitive laboratory mouse strains provide excellent materials for analysis of modifier genes and genetic changes during carcinogenesis. We have generated MSM backcross progeny with the C3H strain, which is extremely sensitive to hepatocarcinogenesis, to construct the present map. RLGS profiles with two combinations of restriction enzymes (NotI-PvuII-PstI, NotI-PstI-PvuII) yielded more than 2000 spots each. The polymorphism rate was about 39.2%, and of a total of 1732 polymorphic spot loci identified, 1371 could be assigned to specific chromosomes by comparison with 79 microsatellite marker loci. Thus, 1450 loci, on all chromosomes except for Y, effectively mapped 90% of the genome (1431.7 cM length). Although some spots might be derived from the same NotI site, each NotI site potentially generating two fragments, the presence of at least 515 loci groups with different progeny distribution patterns dispersed through the genome with an average spacing of 3 cM, means that this genetic map should be useful for analysis of various biological phenomena, including carcinogenesis and ontogenesis, at the gene level.

Animals↗
PubMed2000

So-called mesothelial/monocytic incidental cardiac excrescences obtained during valve replacement surgery: report of three cases and literature review.

We present three cases of so-called mesothelial/monocytic incidental cardiac excrescences (MICE) of the heart and a brief review of related literature. Case 1 was a 51-year-old woman who underwent mitral- and aortic-valve replacement. A tissue sample was submitted as a thrombus attached to the left atrial endocardium. Case 2 was a 69-year-old woman who underwent mitral-valve replacement. The sample was incidentally obtained as whitish clot-like fragments, but its exact origin was not known. Case 3 was a 68-year-old woman who underwent mitral-valve replacement for suspected infective endocarditis. The sample adherent to the pericardium was removed after valvular surgery. Histologically, these lesions were composed of a mixture of plump histiocytoid cells, a papillary arrangement of cuboidal cells, various sized vacuoles, and fibrin. The nests of cuboidal cells resembled cancer cells but showed features of mesothelial cells and no proliferative activity, immunohistochemically or ultrastructurally. In all cases, a suction tube placed in the left atrium was occasionally used to remove overflowing intrapericardial fluid during the surgery. The tip of the suction tube was covered with spiral wire, which is likely to transfer the stripped pericardial mesothelial cells to the left atrium. The significance of MICE is their possibility of being misdiagnosed as metastatic carcinoma by pathologists and a risk of arterial embolization by mesothelial debris clinically.

Aged↗
PubMed2000

Viability of cryopreserved semilunar valves: an evaluation of cytosolic and mitochondrial activities.

BACKGROUND: Despite long-standing, widespread use of cryopreserved allografts, the basic cellular biology of these tissues is still yet unknown. The present investigation was undertaken to study cryopreserved heart valves from the standpoint of cytosolic esterase and mitochondrial dehydrogenase activities. METHODS: Cryopreserved porcine aortic cusps were observed in an unfixed fresh condition with a confocal laser scanning microscope using fluorescent dye. Porcine cusps and cultured human umbilical vein endothelial cells were divided into three groups, including fresh, cold-preserved, and cryopreserved specimens, and cytosolic esterase activity and mitochondrial dehydrogenase activity were analyzed in each. RESULTS: Confocal laser scanning microscope findings disclosed a widely distributed fluorescence in the cusp. Cytosolic esterase activity within human umbilical vein endothelial cells (28%+/-9.0%) after cryopreservation was significantly less than that it was in the cusps (72%+/-21%). Mitochondrial dehydrogenase activity of cryopreserved human umbilical vein endothelial cells and that of cusps fell to 44%+/-6.1% and 64%+/-17% respectively; the difference between the two values was not significant. CONCLUSIONS: Cryopreservation appeared to produce serious damage to cytosolic and mitochondrial functions of endothelial cells. The cytosolic function of cusps, mainly consisting of fibroblasts, was comparatively preserved after cryopreservation, but mitochondrial function of the cusps was more diminished.

Animals↗
PubMed2000

Nanosecond temperature jump and time-resolved Raman study of thermal unfolding of ribonuclease A.

A nanosecond temperature jump (T-jump) apparatus was constructed and combined with time-resolved Raman measurements to investigate thermal unfolding of a protein for the first time. The 1.56-microm heat pulse with 9 ns width at 10 Hz was obtained through the two-step stimulated Raman scattering in D(2) gas involving seeding and amplification. To achieve uniform temperature rise, the counter-propagation geometry was adopted for the heat pulse. The temperature rise was determined by anti-Stokes to Stokes intensity ratios of the 317 and 897 cm(-1) bands of MoO(4)(2-) ions in an aqueous solution. The T-jump as large as 9 degrees C in 10 ns was attained. The unfolding of bovine pancreatic ribonuclease A was monitored with time-resolved Raman spectra excited at 532 nm. The C-S stretching band of Met residues exhibited 10% change of that expected from the stationary state temperature-difference spectra in the initial 200 ns following T-jump and another 10% in 5 ms. The Raman intensity of SO(4)(2-) ions around 980 cm(-1) increased at 100 micros, presumably due to some conformational changes of the protein around the active site. The S-S stretches and tyrosine doublet displayed little changes within 5 ms. Thus, the conformational changes in the initial step of unfolding are not always concerted.

Animals↗
PubMed2000

Active site structure of SoxB-type cytochrome bo3 oxidase from thermophilic Bacillus.

Two-subunit SoxB-type cytochrome c oxidase in Bacillus stearothermophilus was over-produced, purified, and examined for its active site structures by electron paramagnetic resonance (EPR) and resonance Raman (RR) spectroscopies. This is cytochrome bo3 oxidase containing heme B at the low-spin heme site and heme O at the high-spin heme site of the binuclear center. EPR spectra of the enzyme in the oxidized form indicated that structures of the high-spin heme O and the low-spin heme B were similar to those of SoxM-type oxidases based on the signals at g=6.1, and g=3.04. However, the EPR signals from the CuA center and the integer spin system at the binuclear center showed slight differences. RR spectra of the oxidized form showed that heme O was in a 6-coordinated high-spin (nu3 = 1472 cm(-1)), and heme B was in a 6-coordinated low-spin (nu3 = 1500 cm(-1)) state. The Fe2+-His stretching mode was observed at 211 cm(-1), indicating that the Fe2+-His bond strength is not so much different from those of SoxM-type oxidases. On the contrary, both the Fe2+-CO stretching and Fe2+-C-O bending modes differed distinctly from those of SoxM-type enzymes, suggesting some differences in the coordination geometry and the protein structure in the proximity of bound CO in cytochrome bo3 from those of SoxM-type enzymes.

Binding Sites↗
PubMed2000

Structures of reaction intermediates of bovine cytochrome c oxidase probed by time-resolved vibrational spectroscopy.

Structures of reaction intermediates of bovine cytochrome c oxidase (CcO) in the reactions of its fully reduced form with O2 and fully oxidized form with H2O2 were investigated with time-resolved resonance Raman (RR) and infrared spectroscopy. Six oxygen-associated RR bands were observed for the reaction of CcO with O2. The isotope shifts for an asymmetrically labeled dioxygen, (16)O(18)O, has established that the primary intermediate of cytochrome a3 is an end-on type dioxygen adduct and the subsequent intermediate (P) is an oxoiron species with Fe=O stretch (nu(Fe=O)) at 804/764 cm(-1) for (16)O2/(18)O2 derivatives, although it had been long postulated to be a peroxy species. The P intermediate is converted to the F intermediate with nu(Fe=O) at 785/751 cm(-1) and then to a ferric hydroxy species with nu(Fe-OH) at 450/425 cm(-1) (443/417 cm(-1) in D2O). The rate of reaction from P to F intermediates is significantly slower in D2O than in H2O. The reaction of oxidized CcO with H2O2 yields the same oxygen isotope-sensitive bands as those of P and F, indicating the identity of intermediates. Time-resolved infrared spectroscopy revealed that deprotonation of carboxylic acid side chain takes place upon deligation of a ligand from heme a3. UV RR spectrum gave a prominent band due to cis C=C stretch of phospholipids tightly bound to purified CcO.

Amino Acids↗
PubMed2000

A novel diiron complex as a functional model for hemerythrin.

Diiron(II) complexes with a novel dinucleating polypyridine ligand, N,N,N',N'-tetrakis(6-pivalamido-2-pyridylmethyl)-1,3-diaminopropan-2-ol (HTPPDO), were synthesized as functional models of hemerythrin. Structural characterization of the complexes, [Fe2II(Htppdo)(PhCOO)](ClO4)3 (1), [Fe2II(Htppdo)((p-Cl)PhCOO)](ClO4)3 (2), [Fe2II(Htppdo)((p-Cl)PhCOO)](BF4)3 (2') and [Fe2II(tppdo)((p-Cl)PhCOO)](ClO4)2 (3), were accomplished by electronic absorption, and IR spectroscopic, electrochemical, and X-ray diffraction methods. The crystal structures of 1 and 2' revealed that the two iron atoms are asymmetrically coordinated with HTPPDO and bridging benzoate. One of the iron centers (Fe(1)) has a seven-coordinate capped octahedral geometry comprised of an N3O4 donor set which includes the propanol oxygen of HTPPDO. The other iron center (Fe(2)) forms an octahedron with an N3O3 donor set and one vacant site. The two iron atoms are bridged by benzoate (1) or p-chlorobenzoate (2). On the other hand, both Fe atoms of complex 3 are both symmetrically coordinated with N3O4 donors and two bridging ligands; benzoate and the propanolate of TPPDO. Reactions of these complexes with dioxygen were followed by electronic absorption, resonance Raman and ESR spectroscopies. Reversible dioxygen-binding was demonstrated by observation of an intense LMCT band for O2(2-) to Fe(III) at 610 (1) and 606 nm (2) upon exposure of dioxygen to acetone solutions of 1 and 2 prepared under an anaerobic conditions at -50 degrees C. The resonance Raman spectra of the dioxygen adduct of 1 exhibited two peaks assignable to the nu(O-O) stretching mode at 873 and 887 cm(-1), which shifted to 825 and 839 cm(-1) upon binding of (18)O2. ESR spectra of all dioxygen adducts were silent. These findings suggest that dioxygen coordinates to the diiron atoms as a peroxo anion in a mu-1,2 mode. Complex 3 exhibited irreversible dioxygen binding. These results indicate that the reversible binding of dioxygen is governed by the hydrophobicity of the dioxygen-binding environment rather than the iron redox potentials.

Crystallography, X-Ray↗
PubMed2000

Conversion of human colonic adenoma cells to adenocarcinoma cells through inflammation in nude mice.

The roles of inflammation in the malignant progression of tumors during multistep carcinogenesis have been much discussed but remain to be elucidated. To determine the direct contribution of inflammation to colon carcinogenesis, we established a new model of progression of human colonic adenoma cells using a nude mouse; the progression is accelerated by coimplantation of a plastic plate. The FPCK-1-1 cell line, derived from a colonic polyp in a patient with familial adenomatous polyposis, is nontumorigenic when injected subcutaneously into nude mice in a cell suspension of up to 5 x 106 cells per mouse. However implantation of 1 x 10(5) FPCK-1-1 cells attached to a plastic plate induced first acute and then chronic inflammation, and formed progressively growing tumors that were histologically determined as moderately differentiated adenocarcinoma in 65% of mice. Moreover cell lines established from the growing tumors were found to be tumorigenic when injected into mice even without a plastic plate. The tumor arising from the adenoma cells implanted attached to a plastic plate was surrounded by highly proliferating fibrous stroma. This fibrous tissue was considered essential for malignant progression, rather than for attachment to the plastic plate substrate, because the tumors were formed after injection of FPCK-1-1 cells into the fibrous tissue from which the plastic plate had been removed before the cell injection. The conditioned medium (CM) obtained from the fibroblasts derived from a plastic plate-associated stromal tissue was found to contain factors that stimulated growth of FPCK-1-1 cells, but not of the derivative progressor cell lines. The factor was stable to heating and neuraminidase treatment, but labile to trypsin treatment. The main growth-potentiating activity was contained in the fraction larger than 100 kDa. In contrast, the activity to promote FPCK-1-1 cell growth was not present in the CM of subcutaneous fibroblasts from untreated nude mice or the fibroblast cell lines C3H10T 1/2 and NIH3T3. These results demonstrated that inflammation-associated stroma promoted the conversion of colonic adenoma cells to adenocarcinoma cells.

3T3 Cells↗
PubMed2000

Correlation between Propionibacterium acnes biotypes, lipase activity and rash degree in acne patients.

We examined the possible correlation between biotypes of Propionibacterium acnes, lipase activity, and rash degree in acne patients. Among 5 P. acnes biotypes, P. acnes biotype 3 (B3) was the most common, followed by P. acnes biotypes 1, 2 and 4; P. acnes biotype 5 was not found. P. acnes B3 was isolated from more severe skin rashes than those of the other biotypes. Production of propionic acid (PA) and butyric acid (BA) by P. acnes B3 was higher than those by the other P. acnes biotypes. As the rash degree in acne patients was more severe, the production of PA and BA elevated. Although only a few P. acnes strains were examined in the present study, P. acnes B3 had the highest lipase activity and might have the greatest influence on skin rash in acne patients.

Acne Vulgaris↗
PubMed2000

Relationship between Propionibacterium acnes biotypes and Jumi-haidoku-to.

We examined the relationship between Propionibacterium acnes biotypes and Jumi-haidoku-to (JHT). In all the P. acnes strains tested, the production of propionic acid (PA) and butyric acid (BA) was suppressed in a medium containing 1 mg/ml JHT compared with the control medium without JHT. There were no significant differences in the rates of decreased PA and BA production between P. acnes biotype 3 (B3) and the other biotypes or between isolates from mild skin rash and more severe skin rash. P. acnes B3 was the most commonly identified biotype. The clinical effects on acne due to the anti-P. acnes lipase activity of JHT did not seem to be influenced by the degree of acne rash or the P. acnes biotype.

Acne Vulgaris↗
PubMed2000

Mithramycin represses MDR1 gene expression in vitro, modulating multidrug resistance.

The effect of an aureolic acid, mithramycin (MTM) on multidrug resistance (MDR) was investigated. At a concentration of 0.02--0.1 mg/ml (about 20--90 microM), MTM repressed MDR1 gene transcription of SBC-3/ADM, a MDR-phenotype subline derived from human small cell lung tumor. Under the same conditions, another aureolic acid, chromomycin A3, showed potent cytotoxicity. FACS analysis revealed that 5 microm MTM depleted the P-glycoprotein (Pgp) and lowered the efflux activity of SBC-3/ADM cells. Furthermore, MTM sensitized the cells against adriamycin. These results suggest that MTM would be a useful modulator of MDR induced by Pgp.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2000

Preparation of N'-[2-(5,6-dimethylbenzothiazolyl)]-N-furfuryloxamide with plant growth regulatory activity.

The reaction of the N-furfuryloxamic acid sodium salt (12) with 1,1'-oxalyldiimidazole (ODI) yielded the imidazolide (13) as an intermediate, and this directly reacted with 2-aminothiazole derivatives (14) or 2-aminobenzothiazole derivatives (15) under essentially neutral conditions to afford the N'-12-(substituted thiazolyl)]- or N'-[2-(substituted benzothiazolyl)]-N'-furfuryloxamides (6 or 7). The prepared compounds (6 and 7) were examined for plant growth regulatory activity in a seed germination assay. The examination resulted in the discovery of some new revelations that N'-[2-(5,6-dimethylbenzothiazlyl)]-N-furfuryloxamide (7c) at the concentration of 1.0 x 10(-3) M completely inhibited the radicle growth of both rape and leek seedlings.

Allium↗
PubMed2000

Two novel C-glycosides of aureolic acid repress transcription of the MDR1 gene.

In the search for compounds which repress MDR1 gene expression, two novel aryl C-glycosides were isolated from a broth of Streptomyces sp. They had the characteristic structure of a dideoxy-carbohydrate (oliose or olivose) linked directly to chromomycinone, an aglycone of aureolic acids. Further investigation revealed that they were artifacts yielded from an aureolic acid, mithramycin. Acid and methanol were necessary to yield the C-glycosides. This reaction would contribute to the design of useful aryl C-glycosides.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2000

Screening for proteinuria in Japanese schoolchildren: a new approach.

By governmental mandate, Japanese school children are screened annually for proteinuria, hematuria, and glucosuria to identify children with possible renal disorders. We added urine dipstick tests for albumin and creatinine to the Japanese screening protocol, and used their dipstick results for blood, glucose and protein. The sulfosalicylic acid precipitation test was used to confirm "trace" positive protein dipsticks. The Japanese and our screening protocol have in common the same data for glucosuria and proteinuria. Their scheme has an algorithm for repeat testing of children with abnormal results, and further testing and medical evaluation for those showing persistently abnormal values. Out of the 23,121 students, we found seven with likely nephritis, one with confirmed nephritis, one with nephrotic syndrome, 170 with persistent unexplained hematuria, 19 with persistent unexplained proteinuria, 14 cases of urinary tract infection, and 20 cases of likely diabetes mellitus. We conclude that dipstick testing for albumin, protein, creatinine, glucose and occult blood has significant value in a multilevel testing scheme for identifying children with urinary tract abnormalities or diabetes. The assay of albumin increases the sensitivity of the screening, and dividing the albumin by the creatinine concentration reduces the potential errors arising from concentrated or dilute urines.

Adolescent↗
PubMed2000

Hepatocellular carcinoma with extension into the right atrium: report of a successful liver resection by hepatic vascular exclusion using cardiopulmonary bypass.

We report a successful liver resection using cardiopulmonary bypass with, total hepatic vascular exclusion (THVE) for hepatocellular carcinoma (HCC), with extension into the right atrium. A 61-year-old man with a cirrhotic liver was referred to our department with HCC in the medial segment of the left lobe of the liver, and tumor thrombus extending into the right atrium. During surgery, a left lobe and caudate lobe of the liver were transected leaving the left lobe of the liver connected to the inferior vena cava (IVC) by only the left and middle hepatic trunks, and then the intracaval tumor thrombus and the left lobe of the liver were removed en bloc using cardiopulmonary bypass with total hepatic vascular exclusion (THVE). Cardiac arrest was not performed during THVE, and the patient had an uneventful postoperative course and was discharged from the hospital 2 months following surgery. He died of multiple pulmonary metastases 4 years and 8 months after surgery; however, imaging showed no evidence of recurrence in the remnant liver during that period. In conclusion, by performing dissection of the hepatic parenchyma to the hepatic vein prior to removal of the tumor thrombus, the period of extracorporeal circulation, duration of warm ischemic time to the liver, and intraoperative blood loss were all reduced and a radical operation could be performed safely without scattering tumor cells during extirpation of the tumor.

Carcinoma, Hepatocellular↗