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Biomedical subjects

H Fujimoto

Publications and source records attributed to H Fujimoto.

At least 199 records · Page 11Linked to original sources

An exploration of the binding site of aldolase using N-(omega-hydroxyalkyl) glycolamidobisphosphoric esters.

N-(omega-Hydroxyalkyl)glycolamidobisphosphoric esters (P-O-CH2-CO-NH-(CH2)n -O-P), which are analogues of the aldolase (D-fructose-1,6-bisphosphate D-glyceraldehyde-3-phosphate-lyase, EC 4.1.2.13) substrate fructose 1,6-bisphosphate, were synthesized and used for probing its active site. These phosphate compounds competitively inhibited aldolase activity. The Ki value was lowest when the maximum distance between the phosphorus atoms of the bisphosphate was brought close to that of fructose 1,6-bisphosphate. The inhibitor constants, Ki, were compared to those of alkanediol monoglycolate bisphosphoric esters and alkanediol bisphosphate compounds, which were reported previously by Ogata et al. The values of Ki for the bisphosphate compounds containing an amide group, the amide bisphosphate compounds, were smaller than those for the bisphosphate compounds containing an ester group, the ester bisphosphate compounds, and those for alkanediol bisphosphates were the largest for the same distance between phosphorus atoms in these bisphosphates. The difference spectra of aldolase caused by binding of a saturating concentration of N-(omega-hydroxypropyl)glycolamidobisphosphoric ester resembled that of butanediol monoglycolate bisphosphoric ester. However, the effects of the amide bisphosphate compounds on the absorption spectrum of aldolase were smaller than those of the ester bisphosphate compounds for the same distance between phosphorus atoms in these bisphosphate compounds. These results suggest that the synthesized phosphate compounds bind to aldolase at the active site and the -CO-NH- group of the compounds might be held more tightly than the -CO-O- group by hydrogen bonds, presumably with the amino acid residues in the active site, such as Lys-146 or -229 and Asp-33 or Glu-187. On the other hand, the -CO-O- group might be more effective in changing the environment of the Trp-147 residue in the active site of this enzyme.

Animals↗

Regioselective syntheses of trehalose-containing trisaccharides using various glycohydrolases.

Two methods were investigated for the enzymic preparation of trehalose-containing trisaccharides. In the first, a solution of saccharides is circulated through an immobilized-glycosidase column and an activated-carbon column connected in series. In the second, two enzymes having different substrate specificities are sequentially used for condensation and subsequent specific hydrolysis. Thus, 3-O-beta-D-, 4-O-beta-D-, and 6-O-beta-D-galactopyranosyl-alpha,alpha-trehalose; 4-O-alpha-D- and 6-O-alpha-D-glucopyranosyl-alpha,alpha-trehalose; and 4-O-beta-D- and 6-O-beta-D-glucopyranosyl-alpha,alpha-trehalose were synthesized stereo- and regio-selectively.

Antigens, Bacterial↗

Cloning of a hsp70-related gene expressed in mouse spermatids.

A cDNA library of spermatids was screened by a differential hybridization in order to isolate genes expressed in haploid cells of the mouse male germ line. A clone was found that encoded a protein related to the heat shock protein 70. A genomic DNA clone comparable to this cDNA clone was also isolated from a mouse genomic library. This gene had only one continuous open reading frame capable of coding a 630 amino-acid protein. There was an excellent match of the sequence with the heat shock protein 70 family but a difference from any previous 70 kilodalton heat shock protein. A 2.7kb transcript derived from this gene was expressed in spermatids but not in other testicular germ cells and somatic tissues. We have referred to this gene as hsc70t.

Amino Acid Sequence↗

The loop-loosening procedure for urination difficulties after Stamey suspension of the vesical neck.

A main complication of an anti-stress urinary incontinence operation in women is postoperative urinary retention or difficulty in urination caused by the urethrovesical junction being suspended too tightly. A total of 7 women who complained of the complication after a modified Stamey operation underwent our procedure in which the suspension loops were loosened to an adequate tension with the patient under local anesthesia. All patients recovered normal voiding without incontinence immediately after the procedure. The Stamey operation uses a nylon loop for suspension of the urethrovesical junction. Therefore, the tightness of the suspension loop can easily be readjusted postoperatively by the procedure, even though initially the suspension of the urethrovesical junction was too tight or too loose. We believe the procedure will enhance the value of the Stamey operation.

Female↗

In vivo administration of cytokine in allogeneic bone marrow chimeras.

When we analyzed the in vivo efficacy of cytokine administration in murine allogeneic bone marrow chimeras, mitogen-induced responses to ConA, PHA, LPS, or PWM were increased by the in vivo administration of human recombinant granulocyte colony-stimulating factor (rG-CSF), human recombinant interleukin 2 (rIL-2), or WEHI-3B conditioned medium (CM). Furthermore, we found increased alloreactive mixed lymphocyte reactions (MLRs) against donor and/or host type alloantigens in spleen cells from (BALB/c----C3H/He) chimeras, although cytotoxic activity against BALB/c or C3H/He target cells was not detected in spleen cells from these chimeras. Since no significant increase of T cells or Ia positive cells was observed, some functional activation, rather than changes in the cell count, appeared to relate to increase immunoreactivity. An increased IL-2 production in spleen cells from chimeras injected with cytokine was observed shortly after the cessation of cytokine administration. Thereafter, an IL-2 production in these chimeras decreased around 45 days after bone marrow transplantation and then recovered nearly to the control level. An increased IL-2 responsiveness was also observed in spleen cells from these chimeras. These findings suggest that the in vivo administration of rG-CSF as well as rIL-2 or WEHI-3B CM (IL-3) can modulate the immunoreactivity in chimeras via the network of immune systems.

Animals↗

Expression of inhibin alpha-subunit gene during mouse gametogenesis.

Mammalian gametogenesis is regulated through complex interactions between germ and somatic cells. To investigate the mechanism underlying the differentiation of functional gametes, some genes specifically expressed during gametogenesis have been isolated and characterized. In a search for further examples of such genes, we have isolated from a newborn mouse testis cDNA library, a clone corresponding to mouse inhibin alpha-subunit. Although it is known that the inhibin alpha-subunit molecule is abundantly produced in ovarian follicle and in testicular Sertoli cells, the spatial and temporal patterns of expression of this gene remain to be elucidated. In this study, the patterns of expression of inhibin alpha-subunit mRNA during mouse gametogenesis were examined by RNA blot, cytoplasmic dot and in situ hybridization techniques. In the testis, the concentration of inhibin alpha-subunit mRNA increased from about 16 dpc (days post coitum), peaked at birth and then gradually decreased, paralleling testicular development. Inhibin alpha-subunit mRNA was localized in Sertoli cells of wild type as well as W/Wv testes. In adult testis, mRNA was restricted to the perinuclear cytoplasm of Sertoli cells. Inhibin alpha-subunit mRNA was expressed in follicle cells of adult ovary more abundantly than in adult testis. Analysis of expression during folliculogenesis showed that the accumulation of this mRNA began in preantrum follicles and the level of expression reached a maximum in Graafian follicles.

Amino Acid Sequence↗

[Involvements of neuropeptides in pentylenetetrazol-induced convulsion in rats and effects of TRH and ceruletide on the convulsion].

To study the possible involvements of neuropeptides in the occurrence of convulsion, pentylenetetrazol (PTZ) was given to male Wistar rats weighing 250-350 g, and the concentration of neurotensin (NT), and the maximal number of binding sites (Bmax) and dissociation constant (Kd) of NT receptor in the frontal cortex were measured. The effect of the pretreatment of thyrotropin-releasing hormone (TRH) or ceruletide (CER) on the convulsion was also studied. NT was extracted from the homogenates of rat frontal cortex by boiling, and measured by radioimmunoassay. Membrane fractions were incubated with increasing concentrations of 125I-NT. Nonspecific binding was determined in the presence of unlabeled NT and subtracted from total binding to obtain the specific binding. The Bmax and Kd were calculated by Scatchard analysis. Generalized convulsion appeared after intraperitoneal administration of 50 mg/kg PTZ with a latency of 68.2 +/- 4.4 sec. One hour after the administration, neurotensin-like immunoreactivity (NTLI) concentration was reduced from 4.7 +/- 0.6 to 2.3 +/- 0.1 ng/g wet wt (p less than 0.01) and the Bmax of NT receptor from 17.2 +/- 2.8 to 10.8 +/- 1.1 fmol/mg protein (p less than 0.01). However no significant changes were observed in somatostatin-like immunoreactivity (SSLI) concentration and the Bmax and Kd of SS receptor. These facts indicate that PTZ stimulates the release of NT resulting in down regulation of NT receptor. Pretreatment with intracerebroventricular (icv) administration of 30 micrograms/10 microliters NT 30 min before the 50 mg/kg PTZ administration shortened the duration of the convulsion from 135.0 +/- 42.8 to 11.5 +/- 11.9 sec (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

[Study on the localization of human papillomavirus DNA in the vulvar disease by means of in situ hybridization].

We investigated human papillomavirus (HPV) DNA of vulvar diseases obtained from 18 cases of condyloma acuminatum, 3 cases of hyperplastic dystrophy without atypia, 4 cases of lichen sclerosus, 4 cases of Bowenoid papulosis, one case of Bowen disease and 8 cases of squamous cell cancer by in situ hybridization with biotinylated HPV 6, 11, 16 and 18 DNA probes. The results of in situ hybridization analysis showed that HPV 6/11 was positive in 94.4% (17/18) of condyloma acuminatum. In 17 cases of HPV 6/11 positive condyloma acuminatum, 3 cases were positive for HPV 16 and one for HPV 18, respectively. HPV 16 was positive in 75.0% (3/4) of Bowenoid papulosis and one case of Bowen disease was positive for HPV 18. In two cases of Bowenoid papulosis which were positive for HPV 16, cervical carcinoma in situ containing HPV 16 DNA sequences was also found during the follow up period. In 8 cases of squamous cell cancer, 2 cases were positive for HPV 18, one for HPV 16 and one for HPV 6/11. All cases of hyperplastic dystrophy without atypia and lichen sclerosus were negative for HPV DNA. Our results suggested HPV is closely associated with vulvar neoplasia.

Adolescent↗

[Huge splenic metastasis from hepatocellular carcinoma; a case report].

A 62-year-old man was admitted to the hospital because of a left upper quadrant mass. He had undergone treatment for hepatocellular carcinoma for 1 year and 7 months. Dynamic CT and angiography revealed a huge hypovascular mass in the spleen. An autopsy confirmed a splenic metastasis of hepatocellular carcinoma with a massive hemorrhage.

Carcinoma, Hepatocellular↗

Effect of dietary eicosapentaenoic acid on plasma lipids and platelet function in stroke-prone spontaneously hypertensive rat.

An investigation was undertaken to study the effect of EPA in rats fed different protein sources. A highly concentrated EPA (78% EPA, ethyl ester form), manufactured from sardine oil was administered to SHRSP (Stroke-prone spontaneously hypertensive rat) and WKY (Wistar Kyoto) for 4 weeks. Casein or SPI (soy protein isolate) was used as protein source in the experimental diet. In the experiment concerning casein diet, showing significant decrease in systolic blood pressure, plasma lipids of SHRSP were observed after EPA treatment, but no significant difference was found in SPI diet group. Although there was no significant change in systolic blood pressure of WKY after EPA treatment, a similar effect of EPA on plasma lipids level and platelet aggregation were also observed in WKY. However, supplementing methionine to SPI diet induced the reducing effect of EPA in rats. In addition, higher level ratios of EPA to arachidonic acid were observed in the plasma and platelets of rats fed SPI diet containing methionine supplement when compared with rats fed SPI diet. It was suggested that the amino acid profile was related to the effective utilization of EPA in rats.

Animals↗

A genomic clone of Zfy-1 from a YDOM mouse strain detects post-meiotic gene expression of Zfy in testes.

In order to obtain a genomic clone of Zfy-1 from a Y chromosome of Mus musculus domesticus (YDOM) origin, we cloned size-fractionated SJL/J DNA in EMBL-4 and selected colonies which hybridized to pDP1007, a human zinc finger Y clone. The specificity of the clone in hybridizations to mouse and human DNA and partial sequencing confirmed that the clone (subcloned as pGZfy1D) was of Zfy-1 origin. Studies on the expression during testicular development of mRNAs hybridizing to the clone suggested that the gene is expressed post-meiotically.

Aging↗