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T Soga

Publications and source records attributed to T Soga.

At least 37 records · Page 2Linked to original sources
PubMed1999

Is a proton pump inhibitor necessary for the treatment of lower-grade reflux esophagitis?

The efficacy of histamine H2 receptor antagonist (H2RA) and proton pump inhibitor (PPI) therapies in healing reflux esophagitis was compared in a prospective randomized case-control comparative study. A total of 71 patients with grade A to D esophagitis (Los Angeles classification) were given either famotidine 20 mg twice a day (Fam; n = 35) or omeprazole 20 mg once daily (Ome; n = 36) for 8 weeks. Endoscopy was performed to assess healing in 57 patients. Healed patients were followed-up without H2RA or PPI therapy for 3 months. At the end of follow-up, endoscopy was able to be performed in 33 patients. Healing rates for patients in the Fam and Ome groups were 58.6% (17/OFF and 97.4% (27/28), respectively (P < 0.001), and when limited to grade A to B, healing rates were 60.9% (14/23) and 100% (25/25), respectively (P < 0.001). Concerning Helicobacter pylori infection, healing rates for the Fam and Ome groups in H. pylori (+) patients were 90.0% (9/10) and 90.9% (10/11), respectively (P = 1.00). Remission rates in the Fam and Ome groups were 45.0% (91/2)) and 33.3% (6/18), respectively (P > 0.4). In regard to alcohol drinking, remission rates of daily and social drinkers were 7.7% and 42.4%, respectively (P < 0.03). Thus, PPI should be the drug of choice even for healing lower-grade reflux esophagitis, especially in H. pylori (-) patients. Treatment with H2RA may be an alternative choice in H. pylori (+) patients. After healing, most patients cannot sustain remission without maintenance therapy.

Alcohol Drinking↗
PubMed1998

Neurons synthesizing gonadotropin-releasing hormone mRNA subtypes have multiple developmental origins in the medaka.

The origins of the different populations of gonadotropin-releasing hormone (GnRH)-containing neurons in the brains of two genotypes (HO4C; HNI-II) of medaka Oryzias latipes were analyzed at different stages of development (day 1 after fertilization through adulthood), by using oligonucleotide probes specific to salmon-, seabream-, and chicken II-GnRH mRNA and antisera against specific GnRH peptides. Between the two genotypes, there was no difference in the site and time of GnRH expression or the final pattern of GnRH neuronal organization. In the adult fish of both sexes, salmon GnRH mRNA and peptide-containing neurons were seen in the terminal nerve ganglia (nucleus olfactoretinalis; NOR) and chicken II-GnRH mRNA and peptide-containing neurons in the midbrain tegmentum. GnRH cells at the base of the olfactory placode (1-2 cells) and in the midbrain tegmentum were first seen in 1-day-old fish of both genotypes. On day 15, lightly immunoreactive GnRH cells were seen in the NOR of only HNI genotype. By day 30, GnRH expression in the NOR and in the midbrain was prominent. GnRH cells along the basal olfactory bulb and basal telencephalon were occasionally seen in animals 30 days or older. This developmental study shows differential distribution of salmon and chicken II-GnRH mRNA subtypes and emphasizes their separate embryonic origins from the olfactory apparatus (salmon-GnRH) and the ependymal cells of the third ventricle (chicken II-GnRH). The absence of preoptic GnRH hybridization signals, immunoreactivity and the lack of GnRH fibers in the pituitary suggests that the preoptic GnRH neurons are distinct from the olfactory derived-terminal nerve GnRH neurons, and that the GnRH neurites reported in the pituitary of teleost must be of preoptic origin.

Animals↗
PubMed1998

Gene duplication and fusion have occurred frequently in the evolution of phosphagen kinases--a two-domain arginine kinase from the clam Pseudocardium sachalinensis.

In contrast to the 40 kDa arginine kinases from Molllusca and Arthropoda, the adductor muscle of the marine clam Pseudocardium sachalinensis contains an unusual arginine kinase consisting of an 86 kDa subunit. The cDNA encoding the 86 kDa arginine kinase was amplified by PCR and the cDNA-derived amino acid sequence of 724 residues was determined. The exact molecular mass for the protein was calculated to be 80941 Da. The amino acid sequence clearly indicates that Pseudocardium arginine kinase has a two-domain structure: the first domain residues 1-363 and the second domain 364-724. The two domains, which are separated by an intron of 176 bp in the gene, show 62% amino acid sequence identity. This two-domain arginine kinase from a mollusc represents yet another multiple-domain enzyme observed in the phosphagen kinase enzyme family. Two-domain and three-domain enzymes have been observed in three other diverse invertebrate groups. Thus, it is clear that gene duplication and subsequent fusion have occurred frequently, and likely independently, during the course of the evolution of this enzyme family. Comparison of the amino acid sequence in the GS region (a possible candidate for the guanidine substrate recognition site in the phosphagen kinase family) suggests that the first domain of Pseudocardium arginine kinase might not retain a complete enzyme activity, because the Asp-7 in the GS region, which is assumed to be involved in the recognition of the positive charge of arginine, was replaced by a Gly residue in the first domain.

Amino Acid Sequence↗
PubMed1998

Testosterone differentially regulates expression of GnRH messenger RNAs in the terminal nerve, preoptic and midbrain of male tilapia.

The purpose of the present study was to examine the regulation of three molecular variants of gonadotropin-releasing hormone (GnRH)-encoding mRNAs by testosterone in the male tilapia Oreochromis niloticus. Tilapias castrated for two weeks were injected intraperitoneally with sesame oil or 5 microgram/g testosterone for 7 days. In situ hybridization histochemistry was performed using 35S-labelled 30-mer antisense oligonucleotide probes complementary to exon two (bases 1-30) of salmon-, seabream-, and chicken II-GnRH. Computerized image analysis was performed to quantify GnRH mRNA expression in the terminal nerve ganglia (nucleus olfactoretinalis) and in individual cells of the preoptic area and the midbrain tegmentum. Testosterone treatment significantly elevated terminal nerve salmon-GnRH mRNA, reduced preoptic seabream-GnRH mRNA but had no effect on midbrain chicken II-GnRH mRNA levels. The total number and size of preoptic and midbrain GnRH mRNA-containing neurons or the total volume of the terminal nerve ganglia in testosterone-treated animals did not differ significantly from oil-treated animals. The midbrain chicken II-GnRH neurons are not targets of testosterone. These results demonstrate for the first time differential regulation of subpopulations of GnRH neurons with molecular diversity and different topography.

Animals↗
PubMed1998

Simultaneous determination of monosaccharides in glycoproteins by capillary electrophoresis.

A rapid, easy, and reproducible capillary electrophoretic method for the simultaneous determination of acidic, neutral, and amino sugars and sugar alcohols was developed. Underivatized mannuronic acid, glucuronic acid, galacturonic acid, N-glycolylneuraminic acid, N-acetylneuraminic acid, glucosamine, galactosamine, mannose, xylose, glucose, galactose, fucose, ribose, mannitol, sorbitol, xylitol, and inositol were simultaneously determined with indirect UV detection using 2,6-pyridinedicarboxylic acid as a background electrolyte. A highly alkaline pH condition was used in order to charge carbohydrates negatively and to promote migration toward the anode. Electroosmotic flow was reversed to the direction of the anode by adding cetyltrimethylammonium bromide to the electrolyte. The separation of the carbohydrates was investigated by optimizing the operating pH value and satisfactory resolution was obtained at pH 12.1. The relative standard deviations of the method for carbohydrates were between 0.02 and 0.33% for migration times and were greater than 2.7% for peak areas (n = 6). The minimum detectable level ranged from 23 to 71 microM with a 6-nl injection at a signal-to-noise ratio of 3. This method was applied to the composition analysis of monosaccharides in glycoprotein. After acid hydrolysis of fetuin under each optimum condition, sialo, neutral, and amino sugars were quantified under the same electrophoretic condition.

Animals↗
PubMed1998

Synthesis and cytotoxic activity of novel 10-alkylated docetaxel analogs.

An alkylation method of docetaxel at the C-10 position has been established by a radical coupling reaction using a 10-xanthate derivative of 7-O-TES-10-deacetylbaccatin III and appropriate alkenes. In addition the cytotoxic activity of 10-alkylated docetaxel analogs was evaluated. Among these analogs, a derivative having a methoxycarbonyl group at the end of the alkyl moiety exhibited more potent cytotoxic activity than docetaxel.

Alkylation↗
PubMed1998

Quantitative in situ hybridization of three gonadotropin-releasing hormone-encoding mRNAs in castrated and progesterone-treated male tilapia.

We investigated the effects of castration and progesterone administration on the three gonadotropin-releasing hormone (GnRH)-encoding mRNAs in sexually mature male tilapia Oreochromis niloticus. In situ hybridization histochemistry was performed using 35S-labeled antisense oligonucleotide probes complementary to salmon-, seabream-, and chicken II-GnRH cDNAs to quantify cellular GnRH mRNA expression in the terminal nerve ganglia (nucleus olfactoretinalis), preoptic area, and midbrain tegmentum of animals castrated for 2 weeks and injected intraperitoneally with sesame oil or progesterone. Castration significantly elevated salmon-GnRH mRNA but not seabream- or chicken II-GnRH mRNA levels. Progesterone treatment had no effect on salmon-, seabream-, or chicken II-GnRH mRNA levels. Comparisons between intact, castrated, and progesterone-treated animals showed no change in the total volume of nucleus olfactoretinalis, cell sizes, and total numbers of cells expressing GnRH mRNA within the midbrain and preoptic area. These results demonstrate that salmon-GnRH but not seabream- or chicken II-GnRH-synthesizing neurons are under a gonadal steroid negative feedback control and that progesterone might not be the main hormone regulating the three GnRH-encoding mRNAs in the male tilapia.

Animals↗
PubMed1998

Synthesis and evaluation of water-soluble non-prodrug analogs of docetaxel bearing sec-aminoethyl group at the C-10 position.

To develop non-prodrugs of taxoids with satisfactory stability in vivo, high water-solubility, and potent antitumor activity, we prepared several 10-O-sec-aminoethyl docetaxel analogs (3) and evaluated their cytotoxicity against mouse leukemia and human tumor cell lines, microtubule disassembly-inhibitory activity, and water-solubility. These analogs were synthesized from the 10-O-allyl baccatin derivatives (5a-c) using the beta-lactam synthon method. Among these analogs, the 10-O-(2-morpholinoethyl) (18, 21) and 10-O-(2-thiomorpholinoethyl) (19, 24) analogs exhibited cytotoxicity comparable or superior to that of docetaxel (2). In addition, the methanesulfonic acid salt (18a) had a high water-solubility.

Animals↗
PubMed1997

Synthesis and structure-activity relationships of novel 2',2'-difluoro analogues of docetaxel.

To investigate the role of the 2'-hydroxy group at the C-13 side chain of docetaxel in the antitumor activity, we prepared several 2',2'-difluoro derivatives of docetaxel and evaluated their cytotoxicity against mouse leukemia and human tumor cell lines and their microtubule disassembly-inhibitory activity. These analogues were prepared by esterification of protected 10-deacetylbaccatin III (21) with appropriate alpha, alpha-difluorinated carboxylic acids (Charts 1 and 2). Among these 2',2'-difluorodocetaxel derivatives, 2',2'-difluorodocetaxel (23b) was approximately 3-10 times as active as 2'-fluorodocetaxel (29a) in terms of cytotoxicity. In addition, the 3'-(2-furyl) (23h) and 3'-(2-pyrrolyl) (23p) analogues showed activity comparable or superior to that of docetaxel (2).

Animals↗
PubMed1997

A new method to modify the C-4 position of 10-deacetylbaccatin III.

We have developed a new method to modify the C-4 position of 10-deacetylbaccatin III (5) using the C-4 acetoxy anion of the 13-keto derivative (7) and various alkyl halides. The method developed herein should be very useful for the preparation of C-4 modified taxoid analogs.

Alkylation↗
PubMed1997

[An elderly case whose residual malignant lymphoma was completely remitted by oral etoposide treatment using unusual dosing schedule].

In a 72-year-old man with malignant lymphoma (Hodgkin's disease, nodular sclerosis type, Stage III S), complete remission was induced by intravenous drip of adriamycin and oral administration of etoposide. After that, a maintenance dose of etoposide (25 mg) was administered every 3 days without observable side effects. From these results, we considered that the dose level and interval of administration are both important for chemotherapy in elderly patients.

Administration, Oral↗
PubMed1996

In situ hybridization for two differentially expressed GnRH genes following estrogen and triiodothyronine treatment in the brains of juvenile tilapia (cichlid).

Using in situ hybridization, messenger RNAs for gonadotropin-releasing hormone (GnRH) were seen distributed differently in the brains of 40-day-old juvenile tilapia Oreochromis mossambicus. While salmon-GnRH mRNA was localized in the nucleus olfactoretinalis (terminal nerve ganglia), chicken II-GnRH mRNA mRNA was observed in the midbrain nucleus. Various concentrations (0.1-10 mg) of estradiol benzoate and triiodothyronine, given over a 24 h period, had no effects on mRNA levels of salmon- and chicken II-GnRH. Analysis of variance indicated significantly higher levels of salmon- but not chicken II-GnRH mRNA in larger (> 1.5 mm) versus smaller (1.3 mm) brains, among juveniles of the same age and same genetic brood. Thus, salmon-GnRH neurons in the nucleus olfactoretinalis display greater variance depending on the body mass. Since reproductively active tilapia differ with respect to body size at sexual maturation, therefore, besides the age and treatment effects, body size should be taken into consideration.

Animals↗
PubMed1996

Dipole source localization of MEG by BP neural networks.

The purpose of this study was to examine the usefulness of BP neural network for source localization of MEG. Since the performance of this method does not depend on the complexity of brain parameters and source models, a homogeneous brain model and a single current dipole source are assumed for convenience. Localization accuracy was examined in relation to the configuration and scale of the network. As a result, average error for position and moment estimations was within 2% while the maximum error was about 5%. It was therefore concluded that the neural network method, was useful for MEG source localization, though some improvements are still necessary.

Brain↗
PubMed1996

Evaluation of bone density in newborn infants by computed x-ray densitometry.

We evaluated bone density in term and preterm infants using computed x-ray densitometry, which permits measurement of bone density with minimal disturbance to the infants in their incubators. Bone density, bone width, and bone length of the right radius were determined in 155 infants of appropriate weights for their gestational ages (23 to 41 weeks). A curve for intrauterine bone growth was extrapolated from these data. The mean coefficients of variations for variabilities for intra- and interobserver error for all measurements were < 3.5%. In 18 infants, measurements of the right forearm were obtained in two positions to confirm the validity of densitometric measurements. The mean coefficients of variation were 3.42% for bone density, 3.48% for bone width, and 0.21% for bone length. Bone density was significantly correlated with gestational age (r = 0.924) and birth weight (r = 0.921). Bone width and length were also correlated with gestational age (r = 0.866 and 0.937) and birth weight (r = 0.878 and 0.954). Our results suggest that computed x-ray densitometry is a useful method for evaluation of bone density in preterm infants, including those in an intensive care environment.

Absorptiometry, Photon↗
PubMed1996

[Successful therapy with cyclosporine in a case with interstitial pneumonitis associated with polymyositis].

We describe a case of interstitial pneumonitis associated with polymyositis who responded well to cyclosporine therapy. In October, 1993, a 49-year-old female was admitted to our hospital because of fever, muscle weakness and progressive dyspnea. Interstitial pneumonitis with polymyositis was diagnosed and daily oral steroid therapy was started. As the therapy was ineffective, pulse intravenous steroid therapies followed by oral cyclophosphamide and steroid therapy was given. Whereas serum levels of muscle enzymes decreased, she became progressively hypoxemic. No effect was observed in series of therapy including additional pulse steroid therapy, pulse intravenous cyclophosphamide therapy, oral azathioprine and oral bethametazone therapy. In April, 1994, oral cyclosporine was started. After daily oral cyclosporine was combined with steroid, her symptoms, chest X-ray, chest CT and pulmonary function tests significantly improved. Her disease became stable and there was no signs of recurrence since then. It is suggested that cyclosporine is useful for the treatment of progressive interstitial pneumonitis associated with polymyositis.

Cyclosporine↗
PubMed1996

Effect of mizoribine on pulmonary lesions in MRL/lpr/lpr mice.

The present study was made to investigate the effect of mizoribine (MZR), an imidazole nucleoside immunosuppressant, on pulmonary lesions and immunological mode of action of MRL/lpr/lpr mice. Four-week-old female MRL/lpr/lpr mice were injected subcutaneously with 20 mg/kg body weight of MZR every other day. For control, mice were given phosphate-buffered saline (PBS) every other day. MZR caused the delay in the histological development of peribronchial and perivascular lymphocytic infiltrations in the lungs of MRL/lpr/lpr (MRL/lpr) mice. And then, MZR suppressed the number of immunoglobulin (Ig) (IgG and IgM) secreting B cells and anti-DNA-secreting B cells in the spleen of MRL/lpr/lpr mice. The above data indicate that MZR could be useful for the treatment of pulmonary lesions associated with autoimmune disorders such as systemic lupus erythematosus (SLE).

Animals↗