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Y Adachi

Publications and source records attributed to Y Adachi.

At least 649 records · Page 36Linked to original sources
PubMed1992

Identification of nuclear pre-replication centers poised for DNA synthesis in Xenopus egg extracts: immunolocalization study of replication protein A.

We demonstrate by immunofluorescence that a 70-kD protein (P70) purified from Xenopus egg extracts is associated with subnuclear foci (about 200) which we propose to be an assembly of DNA pre-replication centers (preRCs). A cDNA encoding this protein reveals that P70 is the Xenopus homologue of replication protein A (RPA also called RF-A). RPA is know to be a cellular, three-subunit single-stranded DNA binding protein, which assists T-antigen in the assembly of the pre-priming complex in the SV40 replication system. The punctated preRCs exist transiently; they form post-mitotically during the period of nuclear membrane breakdown and disappear during ongoing DNA replication. P70 is homogeneously associated with chromatin at the later stages of the S-phase and is displaced from chromatin post replication, so that P70 cannot be detected on mitotic chromosomes. Double-immunofluorescence studies using biotin-dUTP demonstrate that initiation of DNA synthesis is confined to preRCs, resulting in the punctated replication pattern observed previously by others. PreRCs form efficiently on decondensed chromatin in membrane-free egg extracts if ATP and divalent cations are present. Our results suggest that preRCs are composed of an assembly of a large number of pre-initiation replication complexes poised for initiation at discreet subnuclear regions prior to nuclear reconstruction and initiation of DNA synthesis.

Amino Acid Sequence↗
PubMed1992

Modification of immunopharmacological activities of synthetic monosaccharide lipid A analogue, GLA60, by lysozyme.

Recent studies by our group suggested that lysozyme has a high affinity for bacterial lipopolysaccharide (LPS) of both the smooth and rough forms, and inhibits various immunomodulatory activities of LPS. GLA60 is a synthetic monosaccharide analogue of bacterial lipid A well known as having most of the activities of lipid A with very low toxicity. In this study, we characterized the interaction of lysozyme with GLA60 in comparison to that with Escherichia coli 0111 LPS (smooth form) by means of an immunopharmacological approach. Using dansylated lysozyme (DNS-LZM) as a probe, LZM was found to bind to GLA60. The mitogenic and polyclonal B-cell activating activities were significantly reduced by complex formation. However, there was no inhibitory effect on GLA60 induced production of IL-1 and TNF of macrophages. Interestingly, the activities of macrophages induced by the complex were found to be significantly higher than those induced by GLA60 itself. In contrast, the activities of 0111 LPS were significantly inhibited by LZM. Since the GLA60-LZM complex produced a turbid suspension but the 0111 LPS-LZM complex remained soluble, we consider that the activities of GLA60 alone were mediated by the common functional LPS receptor for dispersed form in both macrophages and B-lymphocytes, but activation of macrophages by the complex was mediated either by another LPS receptor not present in B-lymphocytes or through the phagocytic function of macrophages.

Adjuvants, Immunologic↗
PubMed1992

Inflammatory fibroid polyp of the stomach. Report of three unusual cases.

Three patients with inflammatory fibroid polyp (IFP) of the stomach underwent operation with a diagnosis of submucosal tumor, polyp, and intramural tumor of the stomach, respectively. Resected specimens grossly showed a deep ulcer accompanied by surrounding upheaval, a sausagelike polyp 6.5 cm long, and a pedunculated tumor with a short pedicle, respectively. Histologic examination showed that each lesion was typical of IFP of the stomach, with a mixture of fibroblasts and thin-walled blood vessels, and further by an intense infiltrate of eosinophils. These cases indicate that IFP of the stomach can vary in gross appearance. Practitioners and pathologists must remember that not only a polypoid lesion, but also a pedunculated or even ulcerated lesion, in the gastric antrum may be IFP.

Adult↗
PubMed1992

Fission yeast pap1-dependent transcription is negatively regulated by an essential nuclear protein, crm1.

The fission yeast pap1+ gene encodes an AP-1-like transcription factor that contains a leucine zipper motif. We identified a target gene of pap1, the p25 gene. The 5' upstream region of the p25 gene contains an AP-1 site, and by DNase I footprint analysis, we showed that the pap1 protein binds to the AP-1 site as well as to a 14-bp palindrome sequence. p25 is overproduced when the pap1+ gene is overexpressed, whereas p25 is not produced at all in the pap1 deletion mutant. p25 was previously found to be overproduced in strains carrying cold-sensitive crm1 mutations whose gene product is essential for viability and is thought to play an important role in maintenance of a proper chromosomal architecture. Deletion and site-directed mutagenesis of sequences upstream of the p25 gene demonstrated that the AP-1 site as well as the palindrome sequence are crucial for transcriptional activation either by pap1 overproduction or by the cold-sensitive crm1 mutation; pap1+ is apparently negatively regulated by crm1+. Moreover, we found that cold-sensitive crm1 mutations are suppressed by the deletion of pap1+, further indicating a close relationship between crm1+ and pap1+. The crm1 protein is highly conserved; the budding yeast homolog, CRM1, which complements the fission yeast cold-sensitive crm1 mutation, was isolated and found to also be essential for viability. These results suggest the functional importance of chromosome structure on the regulation of gene expression through the pap1 transcription factor.

Amino Acid Sequence↗
PubMed1992

Tissue distribution of intraperitoneally administered (1-->3)-beta-D-glucan (SSG), a highly branched antitumor glucan, in mice.

Distribution of metabolically 3H-labeled (1-->3)-beta-D-glucan (3H-SSG) obtained from the culture filtrate of Sclerotinia sclerotiorum IFO 9395, in various tissues after intraperitoneal administration into ICR mice (250 micrograms/mouse) was examined. 3H-SSG was mainly detected in liver, spleen, and blood, and a negligible amount was excreted into the feces and excrement within 2 d. The significant amount of 3H-SSG remained in liver and spleen after 1 month. On the other hand, SSG was not incorporated effectively in vivo and in vitro by peritoneal exudate macrophages (0.5 microgram/1 x 10(6) M phi) Similarly in vivo, the majority of 3H-SSG distributed in spleen and liver were recovered from the non-cellular fraction and not from splenic macrophage and Kupffer cell fractions. These results suggested that (1-->3)-beta-D-glucans would not be easily incorporated by the host cells to degrade and exclude from the body even after the onset of the biological response modifier activity.

Animals↗
PubMed1992

The biological fate of sodium prasterone sulfate after vaginal administration. I. Absorption and excretion in rats.

The absorption and excretion of sodium prasterone sulfate (PS) (sodium dehydroepiandrosterone sulfate) were studied in rats after vaginal administration of 14C-PS. In late pregnant rats, maximum plasma level (Cmax) appeared at 2-4 h after dosing and both Cmax and the area under the plasma concentration-time curve (AUC) increased proportionally with increased dose up to 4.0 mg/kg. The radioactivity administered was almost completely recovered from urine and feces during a 72 h postdosing period. The percentages of radioactivity excreted in urine and feces were 58% and 40% of the dose, respectively. The biliary excretion was 46% of the dose within 48 h and about half of the radioactive biliary excreta entered the enterohepatic circulation system. The vaginal absorption of PS was markedly affected by the estrous cycle stage and the progress of pregnancy. The vaginal absorption of PS was predominant at metestrus and diestrus and during late pregnancy.

Absorption↗
PubMed1992

Contributions of various serum proteins to the binding of prasterone sulfate in humans.

The binding of prasterone sulfate (PS) in human plasma was investigated. Binding percentages of PS to human plasma, human serum albumin (HSA), human alpha 1-acid glycoprotein (AGP) and human gamma-globulin (GGL) were independent of the PS concentration between 0.1 and 8.0 micrograms/ml. The mean binding percentages were 99.1% for human plasma, 98.3% for HSA, 12.6% for AGP and 8.1% for GGL. Though PS is an acidic drug, binding of PS to AGP was observed. From the binding index, it was found that PS mainly bound to HSA in human plasma and that the contributions of AGP and GGL to PS in plasma were negligible.

Adult↗
PubMed1992

Antiallergic effect of epinastine (WAL 801 CL) on immediate hypersensitivity reactions: (II). Antagonistic effect of epinastine on chemical mediators, mainly antihistaminic and anti-PAF effects.

Anti-histamine and anti-PAF effects of epinastine were tested in rats, guinea pigs and rabbits. Epinastine showed a potent histamine H1-blocking effect, but the potency was slightly less than that of ketotifen in histamine-induced contraction of guinea pig ileum and histamine-induced cutaneous reactions in rats. In histamine-induced dye leakage into the nasal cavity tested in rats, the drug was slightly more potent than ketotifen and azelastine. Epinastine as well as ketotifen suppressed rabbit platelet aggregation induced by PAF at higher concentrations compared with WEB 2086, a specific PAF-antagonist. In the bronchospasm induced by PAF in guinea pigs, epinastine was more effective than ketotifen in inhibiting the bronchoconstriction, while it showed no remarkable effect on the hypotension induced by PAF. Epinastine caused a potent antagonistic effect on LTC4-induced contraction of isolated guinea pig trachea. In conclusion, the potent anti-histamine, anti-PAF and anti-LT effects of epinastine may significantly contribute to its antiallergic activity.

Animals↗
PubMed1992

[Clinicopathological study of 6 cases of mantle zone lymphoma].

Clinicopathological analyses of 6 cases of mantle zone lymphoma (MZL) were carried out. The median age of the patients was 62 years with a range of 41 to 71 years and the male-to-female ratio was 1:1. Superficial lymph node (LN) swelling was present only in 2 patients. Giant LN swellings of the mesenteric or inguinal regions were present in 4, and bone marrow involvement by lymphoma cells in 5. Serum protein electrophoresis revealed a monoclonal protein of IgM kappa type in 2 patients. One of these also had polyclonal hypergammaglobulinemia. An immunohistochemical study of 6 patients revealed LN-1-(-)+, LN-2+(-)++, sIgM+, sIgD+, CALLA +/-(-)+, DRC-1+(-)++. The immunohistochemical features of the cases were similar to those of small lymphocytic lymphoma or follicular lymphoma. Only 1 patients out of 6 achieved complete remission. Two patients died, one of pneumonia after chemotherapy and the other of cancer. The others were alive 4 to 100 months after the diagnoses. Although giant LN swelling and bone marrow involvement of lymphoma cells which were refractory to treatments were frequently observed, we consider MZL to be a slowly progressive and low-grade type of non-Hodgkin's lymphoma.

Adult↗
PubMed1992

[Efficacy of early use of continuous isoproterenol inhalation therapy for severe asthma attacks in children].

The aim of this study was to evaluate the efficacy and safety of continuous isoproterenol inhalation therapy for asthma attacks in children. We used l-body isoproterenol (Proternol L) in 22 children with 32 episodes of severe attacks. One of them did not respond to this therapy, and two had complications (atelectasis and pneumothorax). Twenty-nine cases were divided into three subgroups according to their clinical scores; A) scores less than or equal to 4, which meant that they were in the early stage of severe attack (n = 9), B) scores 5-6, which meant impending respiratory failure (n = 17), C) scores greater than or equal to 7, which meant respiratory failure (n = 3). The values of SpO2 at the start of this therapy were 94.8, 91.5, 82.0%, respectively. The more severe their attacks were, the lower their SpO2 levels were. The periods until their scores became zero were 0.78, 6.3, 17.2 hours, respectively. There were significant differences between each period respectively (p less than 0.001, p less than 0.01). Heart rates decreased when their symptoms improved, and other adverse effects were not detected. These results suggest that this therapy is effective and safe for children with severe asthma attacks, especially in the early stage.

Administration, Inhalation↗
PubMed1992

[Mode of origin of esophageal squamous cell carcinoma--serial histopathologic and immunohistochemical studies].

I. Serial histopathologic study of esophageal squamous cell carcinoma. A review of 335 cases of squamous cell carcinoma disclosed 55 cases (16.4%) with glandular components in addition to the ordinary component of squamous cell carcinoma, suggesting that this type of esophageal tumor had originated not only from the covering squamous epithelium but from esophageal gland or ductal epithelium. Intra-epithelial carcinoma concomitant with squamous cell carcinoma was seen in 95 cases (28.4%). The incidences of coexistence in such lesion were higher in the groups of early stage esophageal cancer. These observations support the concept of field carcinogenesis of esophageal cancer. II. Histopathologic study of squamous epithelial dysplasia. Among 91 cases without preoperative treatment, there were 40 dysplastic lesions in 23 cases (25.3%). The continuity of dysplasia to the carcinoma was 48.3% and it was often encountered in severe dysplasia rather than in moderate or mild dysplasia, suggesting some relationship between the severity of dysplasia and carcinoma. III. Immunohistochemical study of EGF and c-myc. Among 27 cases, EGF was positive in 10 (37.0%). c-myc was positive in 18 (66.7%) not only cancer but normal epithelium suggesting that some change of products of oncogene occurred also in the normal epithelium of the patients of esophageal cancer.

Carcinoma, Squamous Cell↗
PubMed1992

Non-polypoid inflammatory fibroid polyps concomitant with early carcinoma in the stomach.

A 69-year-old Japanese woman with early carcinoma of the stomach was treated. Postoperative pathological examination of the resected stomach disclosed a widely spreading early carcinoma and two concomitant submucosal lesions which were histologically compatible with inflammatory fibroid polyp (IFP). Neither IFP showed a polypoid appearance: instead they had a down-growth pattern. The covering mucosa was replaced by gastric carcinoma cells. The IFPs were located mainly in the submucosa, but reached invasively to the subserosa through the proper muscular layer. The boundaries of the lesions were well demarcated in the submucosa but poorly demarcated in the subserosa. This case is very rare because the two IFPs showed a down-growth pattern and were concomitant with early gastric carcinoma.

Adenocarcinoma↗
PubMed1992

[Efficacy of continuous isoproterenol inhalation therapy for severe asthma attacks in younger children].

The aim of this study was to evaluate the efficacy of continuous isoproterenol inhalation therapy for severe asthma attacks in younger children, compared with its efficacy in older children. We used l-body isoproterenol (Proternol L) in 31 children with 42 episodes of severe attacks. They were divided into two group according to age: 20 cases under 6 years old (Group A), and 22 cases over 7 years old (Group B). All of the patients except for one in Group B, eventually improved with this therapy. Wood's clinical scores for Group A were significantly higher than those for group B (p < 0.01). In 22 cases whose scores were 5-6, their SpO2 values at the onset of this therapy were 90.8 +/- 3.17 in group A and 92.4 +/- 3.82% in group B. The improvement time of group A (13.6 +/- 16.2 hours) was significantly longer than that of group B (2.5 +/- 5.66, p < 0.01). The nebulized isoproternol doses for group A were 0.47 +/- 0.168 and for group B 0.26 +/- 0.096 mg/kg/saline 500 ml. The dose for group A was significantly higher than that for group B (p < 0.01). We concluded that continuous isoproterenol inhalation therapy was effective even in younger children. But the degree of efficacy was slightly lower in younger children, although they inhaled higher doses of isoproterenal than older children.

Administration, Inhalation↗
PubMed1992

Spermatogenesis in the Watase's shrew, Crocidura watasei--a light electron microscopic study.

Spermatogenesis in the Watase's shrew, Crocidura watasei, was investigated by light and transmission electron microscopy. The cycle of the seminiferous epithelium was divided into 12 stages using the development of spermatids as a main criterion. The steps of spermatids were characterized by morphological changes of the nucleus and acrosomal structure. The relative frequencies of the stages 1 to x 11 were 11.0, 10.3, 6.8, 10.6, 24.0, 6.4, 4.4, 7.9, 6.4, 4.9, 3.7 and 3.6%, respectively. Four types of spermatogonia (A1, A2, In and B) could be discerned by the observation of whole mount samples. The development of spermatids was divided into four phases (Golgi, cap, acrosome and maturation phases), as in other mammals. In Golgi phase of the spermatid, several acrosomal granules were encountered. In cap phase, the acrosome gradually spread over the nuclear surface. In early acrosome phase, the acrosome began to elongate and reached the maximal length in step 8 spermatids. The acrosome of step 8 spermatids was twice as long as that of spermatozoa. In late acrosome phase, the acrosome was on the way of shrinkage. Finally, the fan-shaped acrosome was formed in maturation phase. These findings suggested that the process of acrosomal formation was quite characteristic in the Watase's shrew in that the spermatid acrosome elongated most prominently in the mammals hitherto examined.

Acrosome↗