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Biomedical subjects

T Konishi

Publications and source records attributed to T Konishi.

At least 163 records · Page 9Linked to original sources
PubMed1997

Oxidation of ferric-cytochrome c by N, N'-bis (2-hydroperoxy-2-methoxyethyl)-1,4,5,8-naphthalene tetracarboxylic diimide, NP III--site specific modification of cytochrome c.

When the synthetic hydroxyl radical generator, N, N'-bis (2-Hydroperoxy-2-methoxyethyl)-1,4,5,8-naphthalene-tetracarboxylic diimide, NP III, was photoirradiated in the presence of ferric-cytochrome c (Fe3+), the fragmentation peak corresponding to the specific oxidative modification at the histidine site of cytochrome c was observed in the Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectroscopy (MALDI-TOF) measurement. Without photoirradiation, no such protein oxidation was observed in the experimental conditions employed. This result suggests the possible usage of NP-III as an oxidative protein-modifying reagent.

Binding Sites↗
PubMed1997

Identification of Chlorella T-1 ingredient which enhances DMPO-OH adduct formation in Fenton reaction.

Chlorella T-1 is a micro algae which carries out highly active photosynthetic carbon fixation. For searching the OH scavenging molecules in this strain, the methanol extract of T-1 was fractionated by RP-HPLC and the fractions were analyzed for DMPO-OH formation by ESR after Fenton reaction. In the course of study, a single chlorella T-1 ingredient was found to enhance the formation of DMPO-OH rather than scavenge in the Fenton system. The OH enhancing chlorella component was further purified by chromatography and finally identified as lactic acid by NMR and LC-MS. From the analysis of the reaction conditions for DMPO-OH, it was found that lactic acid did not serve as direct source of OH but accelerated Fenton reaction.

Chlorella↗
PubMed1997

Antibiotic treatment in mice infected with Japanese Borrelia garinii: efficacy of ceftriaxone for eradicating the infection induced by Ixodes persulcatus tick bites.

We compared the efficacy of three antibiotics (ceftriaxone, erythromycin and clarithromycin) against Borrelia garinii infection in mice. The nymphal ticks of Ixodes persulcatus infected with the strain JEM6 of Japanese B. garinii were allowed to feed on female C3H mice. The mice were treated with each of the antibiotics for 5 consecutive days 1, 3, or 7 weeks after tick detachment. The doses of antibiotics per day were as follows: 5 mg intraperitoneal injection of ceftriaxone, 2 mg intraperitoneal injection of erythromycin and 1 mg peroral administration of clarithromycin. The infection status in treated mice was monitored by culturing their earlobes, hearts and urinary bladders in BSK II medium. Ceftriaxone eliminated borreliae completely; however, a recurrence of infection was observed in mice treated with erythromycin and clarithromycin.

Animals↗
PubMed1997

Basaloid-squamous cell carcinoma of the floor of the mouth: characterization of a cell line.

Since it was first described in 1986, basaloid-squamous cell carcinoma (BSC) has been considered a distinct variant of squamous cell carcinoma that occurs in a variety of anatomic sites, including the head and neck region. We report the characterization of the first cell line established from a basaloid-squamous cell carcinoma of the floor of the mouth. The cell line exhibited a highly invasive capacity, indicating that BSC has very aggressive behavior. This cell line may be a useful model for elucidation of the biological characteristics of BSC.

Actins↗
PubMed1997

Purification and properties of methyl formate synthase, a mitochondrial alcohol dehydrogenase, participating in formaldehyde oxidation in methylotrophic yeasts.

Methyl formate synthase, which catalyzes methyl formate formation during the growth of methylotrophic yeasts, was purified to homogeneity from methanol-grown Candida boidinii and Pichia methanolica cells. Both purified enzymes were tetrameric, with identical subunits with molecular masses of 42 to 45 kDa, containing two atoms of zinc per subunit. The enzymes catalyze NAD(+)-linked dehydrogenation of the hydroxyl group of the hemiacetal adduct [CH2(OH)OCH3] of methanol and formaldehyde, leading to the formation of a stoichiometric amount of methyl formate. Although neither methanol nor formaldehyde alone acted as a substrate for the enzymes, they showed simple NAD(+)-linked alcohol dehydrogenase activity toward aliphatic long-chain alcohols such as octanol, showing that they belong to the class III alcohol dehydrogenase family. The methyl formate synthase activity of C. boidinii was found in the mitochondrial fraction in subcellular fractionation experiments, suggesting that methyl formate synthase is a homolog of Saccharomyces cerevisiae Adh3p. These results indicate that formaldehyde could be oxidized in a glutathione-independent manner by methyl formate synthase in methylotrophic yeasts. The significance of methyl formate synthase in both formaldehyde resistance and energy metabolism is also discussed.

Alcohol Oxidoreductases↗
PubMed1997

Regulation of the formate dehydrogenase gene, FDH1, in the methylotrophic yeast Candida boidinii and growth characteristics of an FDH1-disrupted strain on methanol, methylamine, and choline.

The structural gene (FDH1) coding for NAD(+)-dependent formate dehydrogenase (FDH) was cloned from a genomic library of Candida boidinii, and the FDH1 gene was disrupted in the C. boidinii genome (fdh1 delta) by one-step gene disruption. In a batch culture experiment, although the fdh1 delta strain was still able to grow on methanol, its growth was greatly inhibited and a toxic level of formate was detected in the medium. In a methanol-limited chemostat culture at a low dilution rate (0.03 to 0.05 h[-1]), formate was not detected in the culture medium of the fdh1 delta strain; however, the fdh1 delta strain showed only one-fourth of the growth yield of the wild-type strain. Expression of FDH1 was found to be induced by choline or methylamine (used as a nitrogen source), as well as by methanol (used as a carbon source). Induction of FDH1 was not repressed in the presence of glucose when cells were grown on methylamine, choline, or formate, and expression of FDH1 was shown to be regulated at the mRNA level. Growth on methylamine or choline as a nitrogen source in a batch culture was compared between the wild type and the fdh1 delta mutant. Although the growth of the fdh1 delta mutant was impaired and the level of formate was higher in the fdh1 delta mutant than in the wild-type strain, the growth defect caused by FDH1 gene disruption was small and less severe than that caused by growth on methanol. As judged from these results, the main physiological role of FDH with all of the FDH1-inducing growth substrates seems to be detoxification of formate, and during growth on methanol, FDH seems to contribute significantly to the energy yield.

Amino Acid Sequence↗
PubMed1997

Epileptic seizures and event-related potentials (P300) in childhood partial epilepsies.

To clarify the relationship between cognitive function and clinical seizures, auditory event-related potentials (P300) were examined in 72 patients (185 trials) with partial epilepsy. Twenty-six patients (67 trials) had idiopathic partial epilepsies (IPE), and 46 (118 trials) symptomatic or cryptogenic partial epilepsies (SPE). In this study, to rule out the effects of epileptogenesis and other factors, we only examined patients with partial epilepsies undergoing carbamazepine (CBZ) monotherapy at doses of less than 16 mg/kg/day. The results were: 1) the mean age-corrected P300 latency in the patients with SPE (394 +/- 38 msec) was significantly prolonged compared with that in the patients with IPE (378 +/- 28). 2) The prolongation of the P300 latency had no relationship to the seizure frequency, seizure type or seizure duration. 3) In both epileptic groups, there was no significant correlation between the seizure-free period and the age-corrected P300 latency. Our results suggest that the effect of clinical seizures on the cognitive function may be relatively little, and that the cognitive dysfunction in partial epilepsies may mainly originate from epileptogenesis or other factors.

Adolescent↗
PubMed1997

Basic studies on 5-(7-hydroxy-3-O-phosphonocholyl)aminosalicylic acid for the evaluation of microbial overgrowth.

A newly synthesized conjugate of 7-hydroxy-3-O-phosphonocholic acid (ursodeoxycholic acid monophosphate) with 5-aminosalicylic acid (5-ASA-UDCA monophosphate) was investigated to determine its suitability for the evaluation of enteric bacteria. This compound, 5-ASA-UDCA monophosphate, was efficiently deconjugated by cholylglycine hydrolase to release 5-ASA, whereas it was completely resistant to deconjugation by pancreatic and intestinal mucosal enzymes. In everted gut sac experiments, 5-ASA-UDCA monophosphate was not actively absorbed from any part of the small intestine. In animal experiments, urinary excretions of N-acetyl-5-ASA (Ac-5ASA) were measured for 24 h following the oral administration of 20 mg of 5-ASA-UDCA monophosphate. Control rats excreted 276.3 +/- 89.0 micrograms (mean +/- S.E.) of Ac-5ASA, whereas the rats with intestinal bacterial overgrowth excreted more (1224.1 +/- 231.5 micrograms; p < 0.01). These basic studies indicate that this compound is likely to offer a simple method for the evaluation of microbial overgrowth without the use of radioisotopes or expensive, special apparatus.

Aminosalicylic Acids↗
PubMed1997

Problems in the initial diagnosis of renal infarction.

We retrospectively analyzed 20 cases of renal infarction to identify the problems in tentatively diagnosing renal infarction. The subjects consisted of 12 outpatients and 8 inpatients whose diagnosis was confirmed by renal scintigram and/or contrast computed tomography. Renal infarction was tentatively diagnosed in only 4 of the 12 outpatients. Causes of hospitalization were cerebral emboli in 5 cases, peripheral emboli in the extremities in 2 cases and one case involved percutaneous transmitral commissurotomy. On initial urinalysis, 11 cases (55%) showed less than 2+ hematuria using dipsticks to test for occult blood. The mean lactic dehydrogenase value was as high as 2,096 IU while the mean aspartate aminotransferase and mean alanine aminotransferase were 83.1 IU and 78.6 IU. Abdominal ultrasonography revealed abnormalities in only one of 18 cases. In conclusion, since only a moderate degree of hematuria was seen in about half the cases and it was difficult to detect renal abnormalities by ultrasonography, a tentative diagnosis of renal infarction may be difficult in some cases.

Aged↗
PubMed1997

[Clinical analysis of bladder cancer patients treated by radical cystectomy].

We assessed the treatment outcome of 105 patients with transitional cell carcinoma of the bladder treated by total cystectomy at our university hospital, between 1979 and 1993. The patients consisted of 84 men and 21 women (male to female ratio : 4:1), between 45 and 82 years old (mean, 65.5 years old). The overall cancer-specific survival rate at 3 and 5 years was 76.3% and 68.9%, respectively. The 5-year survival rate was 85.2% for grade 2 and 59.9% for grade 3 tumors with a significant difference in the survival curves between the two groups (p < 0.05). The 5-year survival rate according to pathological stage was 100% for pTa, 75.6% for pT1, 78.4% for pT2, 54.0% for pT3 and 39.8% for pT4. A significant difference was observed between pTa and pT3 (p < 0.05), and between pTa-2 and pT4 (p < 0.05). The 5-year survival rate was 72.3% for patients without lymph node involvement and 11.9% for those with lymph node involvement, the difference being significant (p < 0.01). Nineteen patients who received pre- and/or post-operative chemotherapy did not show a higher 5-year survival rate than those who did not.

Aged↗
PubMed1997

[Electron microscopic study on the surface of long-term indwelling silver-protein-coated urethral catheters (Urotopic Ag Protein)].

In order to determine the bacterial and crystal adherence to long-term indwelling urethral catheters, we performed a scanning electron microscopic study utilizing commercially available silver-protein-coated latex (Urotopic Ag Protein) and silicone urethral catheters that were left in place for over 4 weeks. Microorganisms and crystals frequently were associated with fibrillar materials. On the surface of silicone catheters bacteria often were embedded in the amorphous matrix. In contrast we found no bacteria adhering to the antimicrobial urethral catheter surface coated with silver-protein. Crystal formation was similar in both catheters, but no catheteral obstruction was observed in this study. We suggested that antimicrobial urethral catheter coated with silver-protein is applicable to patients who tend to form encrustations on long-term indwelling catheters.

Aged↗
PubMed1997

[Two cases of annulo-aortic ectasia with type A aortic dissection reconstructed by reimplantation of the aortic valve].

We performed aortic valve sparing operation in two cases of annulo-aortic ectasia combined with Type A aortic dissection. Marfan syndrome was found in one case and the dissection was acutely evolving in another case. The aortic valves were observed as normal configuration in both cases and then reimplanted within the synthetic grafts along with the David's procedure. No aortic regurgitation was found in the acute case but slight regurgitation was checked out in the Marfan case at the discharge. The aortic valve preserving operation for annulo-aortic ectasia was considered much effective in cases with aortic dissection in order to expect the thrombolization in the pseudo lumen.

Adult↗
PubMed1997

[Hemo-lymphangioma of the scrotum: a case report].

A 3-year-old boy was referred because of a painless mass in the left scrotum. On palpation, the mass was discriminated from the testis, epididymis and spermatic cord and showed transillumination. A part of the mass was dark purple in color. Total surgical excision of the mass was performed. The lesion was multicystic (2-15 mm), adherent to the scrotal skin, and easily dissectable from the testicle. Pathological examination revealed lymphangioma as a major component and hemangioma as a minor part. He has been free of recurrent disease for 2 years. This is the 7th case of hemo-lymphangioma of the scrotum in the Japanese literature.

Child, Preschool↗
PubMed1997

[Malignant syndrome in multiple system atrophy].

Five of fourteen patients with multiple system atrophy (MSA) experienced a total of eight episodes of malignant syndrome, three episodes in 1, two episodes in 1 patient, and a single episode in each of the other patients. Four patients had extrapyramidal symptoms and required antiparkinson therapy, including dopaminergic agonists. Five episodes occurred in the summer season. Two were caused by decreased or irregular doses of antiparkinson drugs, one by administration of an antidepressant drug, three by complications, and two by elevation of body temperature of environmental origin. A patient without parkinsonism became febrile after administration of droxidopa, which may be a central pyrogenic substance that acts via the noradrenergic system. Administration of dopaminergic drugs and dantrolene sodium was followed by recovery in four episodes in three patients. One patient manifested dysautonomia after recovery from the malignant syndrome. Another patient with high serum creatine kinase levels and myoglobinuria developed renal failure requiring hemodialysis. Another patient died of DIC. Besides withdrawal of dopaminergic agents, which alter monoaminergic neuron activity, stress to the body and heating by a variety of factors tend to trigger the malignant syndrome in MSA.

Adult↗
PubMed1997

[Adenocarcinoma of the bladder producing carcinoembryonic antigen and carbohydrate antigen 19-9: report of a case].

We report a case of primary adenocarcinoma of the bladder producing carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9). An 85-year old woman presented with gross hematuria. Computerized tomography and ultrasonography demonstrated a mass on the urinary bladder. After clinical examination, she was diagnosed with locally invasive bladder cancer. Serum CEA and CA19-9 levels were increased to 8.9 ng/ml (normal < 2.5) and 870 U/ml (normal < 37), respectively. Simple cystectomy and bilateral cutaneous ureterostomy were performed. The histopathological diagnosis was well-differentiated adenocarcinoma of the bladder with invasion through the entire muscle layer. Postoperatively, the serum CEA and CA19-9 levels decreased to 5.4 ng/ml and 53 U/ml, respectively, and both CEA and CA19-9 were detected by immunohistochemical examination of the tumor.

Adenocarcinoma↗