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Biomedical subjects

K Kikuchi

Publications and source records attributed to K Kikuchi.

At least 685 records · Page 38Linked to original sources

Synthetic studies of sesquiterpenes with a cis-fused decalin system, 5. A synthetic approach to the study of structure-activity relationships of the termiticidal norsesquiterpenoids, chamaecynone and related compounds.

Various analogues of chamaecynone [1] were prepared from alpha-santonin, and the termiticidal activity of these compounds was examined. All compounds possessing a 5 beta H-13-noreudesmane skeleton with a ethynyl group at C-7 showed significant termiticidal activity. Changes in the structure of the A-ring of these compounds also influenced the potency of their termiticidal activity.

Animals↗

Monoclonal antibody specifically reacting against 73-kilodalton heat shock cognate protein: possible expression on mammalian cell surface.

The heat shock proteins (hsp) are regarded as being immunogenic to the animal hosts. Although certain hsp are suggested to be expressed on the cell surface, further evidence for the cell surface expression of these proteins has been required. In this article we report the development of a MAb NT22. This antibody reacted with ATP-binding proteins (which contain a large amount of 70-kDa hsp family) of HeLa cells, and with purified bovine 70-kDa hsp. It did not react with the E. coli lysate, but clearly reacted with the recombinant rat hsc73. However, NT22 failed to react with hsp72. Furthermore, stress treatment of cells also indicated that considerable amounts of NT22-defined antigen translocated into the nucleus from the cell cytoplasm. These results suggest that NT22 is a novel MAb that reacts specifically to the mammalian hsc73. Moreover, this antibody could detect the constitutive and stress-induced cell surface expression of its relevant antigen. It is expressed preferentially on EBV-transformed B cell and certain epithelial cancer cell lines. However, resting B cells did not express this antigen on the cell surface. These data indicate that hsc73 could be expressed on the cell surface of certain cells, and suggest that hsc73 may interact with the host immune system.

Adenosine Triphosphate↗

Laparoscopic and minilaparotomy Billroth I gastrectomy for gastric ulcer using an abdominal wall-lifting method.

Laparoscopic distal gastrectomy is still technically difficult because of the lack of appropriate techniques, the expensive laparoscopic instruments, and the use of numerous disposable stapling devices. In an attempt to solve these problems, we have designed a method of laparoscopic and minilaparotomy Billroth I gastrectomy using an abdominal wall-lifting method.

Abdominal Muscles↗

Postantibiotic effects and postantibiotic sub-MIC effects of benzylpenicillin on viridans streptococci isolated from patients with infective endocarditis.

We investigated the postantibiotic effects (PAEs) and the postantibiotic sub-MIC effects of benzylpenicillin on three strains of viridans streptococci isolated from infective endocarditis patients. The PAEs of benzylpenicillin on penicillin tolerant Streptococcus sanguis TW-70 (0.4-3.9 h), penicillin tolerant S. sanguis TW-80 (0.3-6.3 h) and nontolerant Streptococcus oralis TW-186 (0.5-3.1 h) were dependent on exposure time. The PAEs were not concentration dependent for S. sanguis TW-70 and S. sanguis TW-80 above the MIC, and for S. oralis TW-186 above 16 x MIC. The antimicrobial effects of benzylpenicillin at sub-MIC concentrations were examined in bacteria pretreated with benzylpenicillin (8 x MIC) for 2 h and compared with untreated bacteria. At the sub-MICs tested, the regrowth of pretreated S. oralis TW-186 cells was more prolonged than that of untreated cells and bactericidal action was seen only in pretreated cells. These effects (so-called 'postantibiotic' sub-MIC effects') were not observed in penicillin tolerant S. sanguis TW-70. The presence of the postantibiotic sub-MIC effect may be an important factor in determining the dosing regimen for infective endocarditis.

Endocarditis, Bacterial↗

Tissue distribution of isoforms of type-1 protein phosphatase PP1 in mouse tissues and its diabetic alterations.

The amounts of four isoforms of the catalytic subunit of type-1 protein phosphatase, PP1 alpha, PP1 gamma 1, PP1 gamma 2, and PP1 delta have been determined in extracts of various mouse tissues including brain, liver, skeletal muscle, kidney, small intestine, heart, lung, spleen, thymus, and testis by Western blot analysis. Immunoreactive bands for PP1 isoforms were detected at 39.5, 38.5, and 40 kDa for PP1 alpha, PP1 gamma 1, and PP1 gamma 2, respectively, and at 39 and 37 kDa for PP1 delta. The amount of PP1 alpha was at comparable levels in all tissues examined except skeletal and heart muscles, in which it was detected slightly or not detectable, respectively. The amount of PP1 gamma 1 was at higher levels in brain, small intestine, and lung, being 2 to 3 times those in other tissues except heart and spleen, in which PP1 gamma 1 was not detectable. The amount of PP1 gamma 2 was extremely large in testis, small in brain, lung, spleen, and thymus, but it was not detectable in the other tissues. The amount of PP1 delta was at comparable levels in all the tissues except skeletal muscle, in which it was at a low but detectable level. Then, the amounts of the four PP1 isoforms were determined in non-obese diabetic (NOD) mice. The amounts of PP1 alpha were progressively decreased in livers of NOD mice as a function of increasing concentrations of blood glucose, whereas the amounts of PP1 gamma 1 and PP1 delta were unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

pH-sensitive dissociation and association of beta-N-acetylhexosaminidase from boar sperm acrosome.

beta-N-Acetylhexosaminidase (beta-Hex, EC, 3.2.1.52) was released from cauda epididymal boar sperm by treatment with ionophore A23187, indicating that this enzyme is localized in the acrosome. beta-Hex was extracted on a large scale, with 2% acetic acid containing 0.2% Brij 35, from washed ejaculated sperm. By gel filtration chromatography, beta-Hex was separated into a high-molecular-weight fraction (beta-Hex I) and a low-molecular-weight fraction (beta-Hex I). beta-Hex I, which is predominant under acidic conditions (pH 6.5), dissociated into beta-Hex II under alkaline conditions (pH 7.4). beta-Hex II, converted from beta-Hex I, associated again to form beta-Hex I under acidic conditions. By sequential chromatography on ion-exchange, lectin, gel filtration, and ion-exchange HPLC columns, beta-Hex I and II were purified 1200-fold and 4000-fold, respectively, with a combined recovery of 23% as measured with synthetic substrate. An inhibitor of beta-Hex, O-(2-acetamido-2-deoxy-D-glucopyranosylidene) amino N-phenyl-carbamate (PUGNAC), reduced the in vitro fertilization rate in porcine cumulus-enclosed eggs, but barely changed the rate when cumulus-free eggs were used. beta-Hex I was shown to possess cumulus dispersion activity, suggesting that beta-Hex plays a role in the passing by sperm through cumulus cells before they bind to the zona pellucida.

Acetylglucosamine↗

A cooperative randomized controlled study of adjuvant chemoendocrine therapy for breast cancer in Japan.

A randomized trial was carried out in 55 Japanese institutions to examine the significance of postoperative adjuvant chemoendocrine therapy in Stages II and IIIA breast cancer patients after radical mastectomy. A total of 619 patients were entered from November 1982 to November 1984, of whom 554 were eligible. Patients were administered MMC (13 mg/m2) after surgery, and were randomized by the envelope method into either group A (ftorafur, 400 mg/m2/day; 275 patients), or group B (ftorafur, 400 mg/m2/day, and tamoxifen, 20 mg/day; 279 patients). Treatment was continued for 1 year from postoperative day 7. There were no significant differences between the two groups with regard to age, menopausal status, ER status, method of operation, stage, or number of positive lymph nodes. There was also no significant difference between the two groups in the 5-year survival and disease-free survival (DFS) rates (Kaplan-Meier method). Stratification by ER status, nodal status, or menopausal status produced no significant differences between the groups. However, postmenopausal patients and lymph node-positive patients who were also ER-positive showed a significantly higher DFS in group B. Furthermore, group B in ER-positive patients with four or more positive lymph nodes also had a higher survival rate.

Adult↗

Selective increases in isoform PP1 alpha of type-1 protein phosphatase in ascites hepatoma cells.

The amounts of four isoforms of the catalytic subunit of type-1 protein phosphatases, PP1 alpha, PP1 gamma 1, PP1 gamma 2, and PP1 delta, have been determined in extracts of rat ascites hepatomas, AH131A, AH13, AH13NMOR, AH143A, and Yoshida sarcoma, and compared to those of rat liver by Western blot analysis. The amount of PP1 alpha was increased over three times in all five hepatomas. The amount of PP1 gamma 1 was increased over two times in AH13, AH13NMOR, and AH143A. The amount of PP1 delta was selectively increased about 4 times in AH131A and AH143A. The PP1 gamma 2 protein was undetectable in both liver and hepatomas. There was good parallelism between the general increase in only PP1 alpha protein in the hepatomas and the previous data demonstrating the general increase in PP1 alpha mRNA in numerous ascites hepatomas. These results suggest that PP1 alpha plays important roles in the expression of malignant phenotype, that its amount is under strict control at the transcription level, and that PP1 gamma 1 and PP1 delta play different roles in the expression of some phenotype(s) of the ascites hepatomas.

Amino Acid Sequence↗

Transformation-associated 86 kDa natural killer target molecule expressed on the mouse, rat and human cell surface.

We previously reported on the 86 kDa natural killer target molecule associated with transformation of the oncogene-transfected rat fibroblasts. This molecule may participate in the lethal hit phase of cytotoxicity by natural killer (NK) cells. Originally, this molecule was defined by mAb109, but mAb109 could react only with rat tumor lines. In this report, to determine whether the 86 kDa molecule could be utilized as a natural killer target molecule in mammalian cells, we developed a polyclonal anti-86 kDa antibody (pAb109). Our data indicated that pAb109 preferentially reacted with NK-susceptible lines such as mouse YAC-1, rat W31 and human K562 cells, but reacted only weakly with NK-resistant mouse EL-4, rat fetal fibroblast WFB and human fetal fibroblast HEPM. In a cytotoxicity experiment, pAb109 F(ab')2 fragments could inhibit the cytolysis by NK cells of W31 and K562 cells. However, these fragments did not inhibit the cytotoxicity of non-NK cells such as CD3+, CD4-, CD8- T cell receptor alpha beta- T cells (presumably gamma delta T cells) to W31 cells. Taken together, these data suggest that the cell transformation-associated 86 kDa molecule may be critical in NK cytotoxicity, and a candidate for the NK target structure in mammalian tumor cells.

3T3 Cells↗

1C5 antigen: cancer-associated protein expressed by cervical adenocarcinomas and beta-casein.

The monoclonal antibody 1C5 reacts with an antigenic determinant present in 90% of the cases of adenocarcinoma of the uterine cervix. The antigen defined by the 1C5 antibody exhibits immunological characteristics similar to those of skim milk (bovine buttermilk). 1C5-defined antigen obtained from tumor extract and skim milk binds specifically to wheat germ agglutinin (WGA) lectin. The 1C5-defined antigenic activity of a WGA lectin-bound fraction was eluted at 0.7-0.8 M NaCl off a Mono Q column. Use of an inhibition assay and a dot immunobinding assay revealed that the antigenic epitope defined by the 1C5 MoAb from skim milk exists within the first 28 amino acids of the beta-casein peptide.

Adenocarcinoma↗

[Microbiological and clinical studies of vancomycin resistant Leuconostoc spp. and Pediococcus spp. isolated from septicemia patients].

We described three septicemia cases in which blood cultures yielded gram-positive cocci identified as Leuconostoc spp. and Pediococcus spp. Patients were three male adults aged 63 to 71 years with severe underlying diseases, pancreatic cancer, esophageal cancer and diabetes mellitus with chronic renal failure. They had fever and chills at the onsets of septicemia with acute obstructive suppurative cholangitis, acute pneumonia, and infection complicated with invasion sites of esophageal cancer contagious to bronchus and subcutaneous tissue. Blood cultures yielded catalase and oxidase negative highly vancomycin-resistant (MIC: 1024 micrograms/ml <) gram-positive cocci showing alpha or gamma hemolysis on blood agar plates. Two cases were polymicrobial infections. In one case with esophageal cancer, clinical symptoms persisted after the start of antimicrobial chemotherapy and the patient died 10 days later associated with complications of esophageal cancer. Leuconostoc lactis, Leuconostoc mesenteroides subsp. dextranicum, and Pediococcus acidilactici wee identified by physiological reactions. These strains were also highly resistant to teicoplanin and fosfomycin, and tolerant to all rested beta-lactams such as benzylpenicillin. This is the first report in Japan to our knowledge on the identification of Leuconostoc spp. and Pediococcus spp. isolated from human infectious diseases.

Aged↗

[Microbiological and clinical studies of infective endocarditis due to nutritionally variant streptococci].

We report four cases of infective endocarditis due to nutritionally variant streptococci (NVS) that occurred between 1981 and 1991. Three female and one male patients had underlying heart diseases. Causative organisms showed satellitism to staphylococci. Two strains were identified as S. adjacens and the other two were identified as S. defectivus by DNA-DNA hybridization. All strains had tolerance and one strain had resistance to benzylpenicillin (MIC 4 micrograms/ml). This penicillin-resistant strain also had tolerance to gentamicin. There was no synergism of benzylpenicillin and gentamicin against this strain by a killing curve in vitro. A 11-year-old female patient with infective endocarditis due to this strain, who had a transposition of great arteries, had large vegetations in external conduits by the Rastelli's operation. Some intensive antimicrobial chemotherapies were unsuccessful and a surgical replacement of the conduits must be done in this case. Since infective endocarditis due to NVS is not rare in Japan, NVS should be considered for the causative organisms in culture negative endocarditis.

Adult↗

Restriction fragment length polymorphism analysis of clinical isolates of Mycobacterium haemophilum.

Mycobacterium haemophilum is an emerging opportunistic pathogen, and since 1989, infections caused by this organism have been identified more frequently in the New York City area than in any other region of the United States. A DNA fingerprinting method, based on restriction fragment length polymorphisms (RFLPs) was developed. A genomic library of M. haemophilum isolate 1A was constructed; screening the library yielded a recombinant strain that incorporated a genetic element present in multiple copies in the M. haemophilum genome. This clone was used to produce a probe for RFLP analyses of PvuII digests of genomic DNA. We used this probe to determine the RFLP patterns of 43 clinical isolates of M. haemophilum from 28 patients. A total of six distinct patterns were observed. Two patterns, designated types 1 and 2, accounted for 91% of the infections in patients from the New York City area. Two isolates from Arizona had identical patterns but were distinct from those of New York isolates, and an isolate from Israel, the type strain, had another distinct pattern (type 6). The type 6 pattern was also seen in a recent isolate from Norway. All of the type 1 isolates and 60% of the type 2 isolates were recovered from patients with AIDS in the New York City area. This molecular subtyping method should provide a useful tool for epidemiological studies and may help identify the associated risk factors, vehicles, and possible reservoirs of this newly emerging pathogen.

AIDS-Related Opportunistic Infections↗

Transforming growth factor beta 1 as a prognostic factor in pulmonary adenocarcinoma.

AIMS: To evaluate the efficacy of transforming growth factor beta (TGF-beta) for the prognosis of pulmonary adenocarcinoma. METHODS: TGF-beta was detected immunohistochemically using the avidin-biotin-peroxidase complex technique in resected pulmonary adenocarcinomas from 88 patients. RESULTS: Of the 88 patients, 39 were TGF-beta negative and 45 TGF-beta positive. The five year survival rate was 56% for the TGF-beta negative and 16% for the TGF-beta positive group. CONCLUSIONS: TGF-beta can be used as a prognostic factor in pulmonary adenocarcinoma.

Adenocarcinoma↗

Serum concentration of 7S collagen and prognosis in patients with the adult respiratory distress syndrome.

BACKGROUND--7S collagen, an N-terminal peptide of type IV collagen, is a primary constituent of the basement membrane. To evaluate whether the serum concentration of 7S collagen reflects the severity of inflammatory lung disease, the serum concentration of 7S collagen was measured in patients with adult respiratory distress syndrome (ARDS) and idiopathic pulmonary fibrosis (IPF). METHODS--A radioimmunoassay was used for the measurement of 7S collagen. Gas exchange abnormality was expressed as the arterial oxygen tension (PaO2) divided by the fractional concentration of inspired oxygen (FiO2). RESULTS--The mean (SD) concentration of 7S collagen was 2.7 (0.9) ng/ml in 10 healthy subjects, 5.0 (1.5) ng/ml in 11 patients with IPF, and 14.8 (9.7) ng/ml in 13 patients with ARDS. Significant differences were observed between the patients with ARDS and both healthy subjects and the patients with IPF. In the patients with ARDS serum concentrations of 7S collagen were strongly related to PaO2/FiO2 (r = -0.61). Moreover, the mean (SD) serum concentration of 7S collagen in the eight patients with ARDS who died (19.5 (10.2) ng/ml) was considerably higher than that of the five who survived (7.1 (2.1) ng/ml). CONCLUSION--These results suggest that serum levels of the 7S fragment of type IV collagen may have some prognostic value in ARDS.

Adolescent↗

Long-term administration of L-arginine improves nitric oxide release from kidney in deoxycorticosterone acetate-salt hypertensive rats.

To examine the effects of L-arginine (L-Arg) on endothelial function, we administered 0.5 g/L L-Arg in drinking water to deoxycorticosterone acetate (DOCA)-salt rats for 8 weeks and then measured nitric oxide (NO) release from isolated kidneys using a newly developed real-time chemiluminescence method. Renal pathology was also analyzed. Acetylcholine caused much smaller declines in renal perfusion pressure (10(-7) mol/L acetylcholine: -24 +/- 2% [SEM] versus -50 +/- 2%, P < .001) and NO release in DOCA-salt rats (+3 +/- 1 versus +33 +/- 3 fmol/min per gram kidney weight, P < .001) compared with control rats. L-Arg did not influence the time course of systolic blood pressure elevation in DOCA-salt rats (211 +/- 5 versus 208 +/- 6 mmHg, DOCA versus L-Arg/DOCA, P = NS). However, oral administration of L-Arg improved acetylcholine-induced declines in renal perfusion pressure (10(-7) mol/L acetylcholine: L-Arg/DOCA, -39 +/- 3%, P < .01 versus DOCA). This change was associated with an increase in NO release by acetylcholine (10(-7) mol/L acetylcholine: L-Arg/DOCA, +10 +/- 1 fmol/min per gram kidney weight, P < .05 versus DOCA). However, morphological changes in renal vessels and glomeruli were similar between DOCA and L-Arg/DOCA rats. These results suggest that L-Arg administration partially reverses renal endothelial function with respect to vasorelaxation and NO release independent of blood pressure changes, indicating that hypertensive vessels seem to be depleted of L-Arg and/or have defects in the availability of L-Arg for NO synthesis.

Acetylcholine↗

Elevated levels of interleukin-8 and leukotriene B4 in pulmonary edema fluid of a patient with reexpansion pulmonary edema.

We experienced a case of reexpansion pulmonary edema (RPE) after surgical treatment of pneumothorax. In this case, protein leakage and polymorphonuclear leukocyte (PMN) accumulation were observed in the reexpanded lung. Interleukin-8 and leukotriene B4 in edema fluid were increased at the onset of RPE. PMN elastase was also increased, though its peak was delayed. The plasma level of P-selectin, which mediates adhesion between PMN and endothelium, was elevated. We speculate that some of these fluid mediators may play important roles in chemotaxis and activation of PMN in the development of RPE.

Adult↗

Rapid activation of rat insulin-like growth factor-I gene transcription by growth hormone reveals no alterations in deoxyribonucleic acid-protein interactions within the major promoter.

Insulin-like growth factor-I (IGF-I) is an important mediator of prenatal and postnatal growth, but little is known about the control of IGF-I gene expression. Previously, we demonstrated that GH rapidly stimulates hepatic IGF-I transcription in vivo in hypophysectomized (hypox) rats. In this study, we show that GH induces IGF-I gene transcription through the major promoter, promoter 1, and identify and characterize DNA-protein interactions throughout the promoter. In vitro deoxyribonuclease-I footprinting was used to analyze 1711 nucleotides of promoter 1 and the entire 328-nucleotide 5'-untranslated region of exon 1, using hepatic nuclear protein extracts from male juvenile hypox rats given a single ip injection of GH or saline 60 min before death. Fourteen DNA-protein binding sites were identified, with 6 located in the highly conserved 5'-untranslated region of exon 1. These latter sites were further characterized for specificity and regulation by GH, using gel mobility shift assays. Two of these DNA-protein interactions were also detected by in vivo dimethylsulfate footprinting. All DNA-protein binding was seen using hepatic nuclear protein extracts from hypox rats and did not change within 15, 30, 60, or 120 min after treatment with GH. Our results thus define a series of constitutive DNA-protein interactions within the major rat IGF-I gene promoter that may be involved in mediating GH-activated nuclear signals to initiate IGF-I transcription.

Amino Acid Sequence↗