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Biomedical subjects

Y Yanagawa

Publications and source records attributed to Y Yanagawa.

At least 19 recordsLinked to original sources
PubMed2009

Preferential labeling of inhibitory and excitatory cortical neurons by endogenous tropism of adeno-associated virus and lentivirus vectors.

Despite increasingly widespread use of recombinant adeno-associated virus (AAV) and lentiviral (LV) vectors for transduction of neurons in a wide range of brain structures and species, the diversity of cell types within a given brain structure is rarely considered. For example, the ability of a vector to transduce neurons within a brain structure is often assumed to indicate that all neuron types within the structure are transduced. We have characterized the transduction of mouse somatosensory cortical neuron types by recombinant AAV pseudotyped with serotype 1 capsid (rAAV2/1) and by recombinant lentivirus pseudotyped with the vesicular stomatitis virus (VSV) glycoprotein. Both vectors used human synapsin (hSyn) promoter driving DsRed-Express. We demonstrate that high titer rAAV2/1-hSyn efficiently transduces both cortical excitatory and inhibitory neuronal populations, but use of lower titers exposes a strong preference for transduction of cortical inhibitory neurons and layer 5 pyramidal neurons. In contrast, we find that VSV-G-LV-hSyn principally labels excitatory cortical neurons at the highest viral titer generated. These findings demonstrate that endogenous tropism of rAAV2/1 and VSV-G-LV can be used to obtain preferential gene expression in mouse somatosensory cortical inhibitory and excitatory neuron populations, respectively.

Animals↗
PubMed1992

[Pharmacokinetics and toxicological study on the intraperitoneal administration of cisplatin and etoposide in gynecological malignancies].

We administered cisplatin and etoposide into the peritoneal cavity of 13 postoperative patients with gynecological malignancies, and studied the pharmacokinetics and toxicity in the combination of both drugs. Cisplatin 100 mg/body and etoposide 200 mg-400 mg/body were mixed together in 500 ml or 1,500 ml of normal saline and administered intraperitoneally on the day of operation and two or three weeks later. The peritoneal peak level of free cisplatin, diluted with 500 ml, was about two times higher than that, diluted with 1,500 ml. However, there was no difference in the peritoneal and plasma AUC. The peritoneal level and AUC of etoposide, diluted with 500 ml, was about two times higher than that, diluted with 1,500 ml. Among the groups of 1,500 ml, peritoneal and plasma levels and AUC were almost proportional to the doses. Nausea and vomiting were experienced in all patients. With the increase of etoposide, more marrow suppression was observed. However, we encountered no other significant side effects. In conclusion, intraperitoneal administration of cisplatin and etoposide in this setting can be used safely with minimum side effects, and the dilution of 1,500 ml seems to be better.

Adult↗
PubMed1991

Stimulation of DNA synthesis in Jurkat cells by synergistic action between adenine and guanine nucleotides.

P2-purinoceptor agonists stimulated the DNA synthesis of Jurkat cells via a pathway independent of cAMP and intracellular free calcium. The response was greatly enhanced by the synergistic action between adenine and guanine nucleotides, suggesting that binding sites of these nucleotides are different from each other, and the proliferation is stimulated by a novel interaction between adenine and guanine nucleotide receptors. The stimulatory effects of P2-agonists on proliferation was completely abolished by cholera toxin and attenuated by pertussis toxin, which suggests that substrates for cholera toxin and pertussis toxin are involved in the proliferative pathways associated with P2-purinoceptors.

Adenine Nucleotides↗
PubMed1991

Tertiary structure of conotoxin GIIIA in aqueous solution.

The three-dimensional structure of conotoxin GIIIA, an important constituent of the venom from the marine hunting snail Conus geographus L., was determined in aqueous solution by two-dimensional proton nuclear magnetic resonance and simulated annealing based methods. On the basis of 162 assigned nuclear Overhauser effect (NOE) connectivities obtained at the medium field strength frequency of 400 MHz, 74 final distance constraints of sequential and tertiary ones were derived and used together with 18 torsion angle (phi, chi 1) constraints and 9 distance constraints derived from disulfide bridges. A total of 32 converged structures were obtained from 200 runs of calculations. The atomic root-mean-square (RMS) difference about the mean coordinate positions (excluding the terminal residues 1 and 22) is 0.8 A for backbone atoms (N, C alpha, C). Conotoxin GIIIA is characterized by a particular folding of the 22 amino acid peptidic chain, which is stabilized by three disulfide bridges arranged in cage at the center of a discoidal structure of approximately 20-A diameter. The seven cationic side chains of lysine and arginine residues project radially into the solvent and form potential sites of interaction with the skeletal muscle sodium channel for which the toxin is a strong inhibitor. The present results provide a molecular basis to elucidate the remarkable physiological properties of this neurotoxin.

Amino Acid Sequence↗
PubMed1991

p53 gene mutations in colorectal tumors from patients with familial polyposis coli.

The p53 gene has been elucidated as a tumor suppressor gene, and inactivation of this gene caused by deletion or point mutations may play a crucial role in the development of human malignancies. In colorectal carcinomas with an allelic deletion of the p53 gene, the remaining p53 gene was mutated with considerable frequency. It is most difficult to detect point mutations or small deletions of the gene because the mutations occur in diverse regions, although four hot spots have been observed [J.M. Nigro et al., Nature (Lond.), 342: 705-708, 1989]. The polymerase chain reaction and denaturing gradient gel electrophoresis facilitate detection of mutations in the hot spots of the p53 gene. Using these methods, we detected mutations in three adenomatous polyps and one carcinoma from familial polyposis coli patients and three carcinomas of sporadic cases. The DNA sequence analysis confirmed mutations of the p53 gene in 2 adenomas (13 base-pair deletions in one and a point mutation in the other) and 1 carcinoma (point mutation) from familial polyposis coli patients. These results suggest that the p53 gene mutations may be involved in the formation not only of carcinomas but also of adenomas which occur in familial polyposis coli patients.

Adenomatous Polyposis Coli↗
PubMed1991

[Diagnosis of colorectal cancer from DNA level].

The inherited cancer-inducing disease familial polyposis coli (FPC) provides an excellent model not only for studying tumor progression in colorectal cancer but also for elucidating molecular mechanisms in general oncogenesis. This paper reviewed recent remarkable progresses of molecular mechanisms in colorectal tumorigenesis. This is concerned with the various kinds of genetic alterations that accumulate in the development from normal mucosa to adenoma, and then to adenocarcinoma in comparison with FPC and sporadic cases. This review included also information on the localization of FPC major gene. These observations indicate that in cases of colorectal tumorigenesis several genetic alterations may be involved, including activation of K-ras gene, deregulated expression of c-myc gene or c-fos gene and inactivation of tumor suppressor genes such as p53 and DCC genes, as well as the loss of heterozygosity. The observation suggest that adenomas will have undergone several gene or chromosome mutations before reaching to the fully malignant state. Therefore, DNA diagnosis for colorectal tumors in the clinical level may contribute to more accurate prognosis and better results for further therapy.

Adenoma↗
PubMed1990

Expression of the human MHC, HLA-DQW6 genes alters the immune response in C57BL/6 mice.

In an attempt to obtain direct evidence for the critical role of HLA class II molecules in regulating the immune response, genomic genes for alpha- and beta-chains of HLA-DQw6 from HLA-Dw12 haplotype were introduced into the C57BL/6 (B6) strain of mouse and a line of HLA-DQw6 transgenic mouse was obtained. Tissue specificity of the expression of the transgenes was much the same as that of murine I-Ab genes. DQw6 molecules were expressed on B cells and macrophages in spleen cells and about 30 to 40% of the I-Ab+ spleen cells were positive for DQw6. The HLA-DQw6 transgenic B6 mouse became tolerant to the DQw6 molecules, as evidenced by the MLR and antibody production specific to the DQw6 molecules. The HLA-DQw6 transgenic B6 mouse showed a strong immune response to streptococcal cell wall antigen (SCW), whereas the B6 mouse was a low responder to SCW. The SCW-specific T cell line was established from the transgenic mouse and this T cell line recognized SCW in the context of HLA-DQw6 molecules expressed on the mouse L cell transfectant or on human monocytes. The proliferative response to SCW of primed lymph node T cells and the SCW-specific T cell line derived from the transgenic mice was inhibited by anti-HLA-DQ mAb. Thus, it is clear that the HLA-DQw6 genes acted as major histocompatibility genes in these transgenic mice.

Animals↗
PubMed1990

Conotoxin GIIIA: selective inhibition of 22Na influx via voltage-dependent Na channels in adrenal medullary cells.

Conotoxin GIIIA and GIIIB from the marine snail Conus geographus have been reported to inhibit voltage-dependent Na channels in skeletal muscle and postganglionic sympathetic neuron, but have no effect on Na channels in brain, giant axon and heart. In eel electroplax, conotoxins were also shown to share the common binding sites with saxitoxin (see review Gray et al. 1988). In bovine adrenal medullary cells, conotoxin GIIIA inhibited veratridine-induced influx of 22Na, 45Ca and secretion of catecholamines with an IC50 of 6 mumols/l while saxitoxin suppressed veratridine-induced responses with an IC50 of 6.3 nmol/l. [3H]Saxitoxin binding to the cells was inhibited by unlabeled saxitoxin with an IC50 of 5.1 nmol/l, but was slightly reduced by 10 mumols/l conotoxin GIIIA. Conotoxin GIIIA, at 10 mumols/l, did not alter carbachol-induced influx of 22Na, 45CA and secretion of catecholamines as well as high K-induced 45Ca influx and catecholamine secretion. These results indicate that conotoxin GIIIA, at concentrations 950 fold higher than saxitoxin, inhibits Na influx via voltage-dependent Na channels, but has no effect on the nicotinic receptor-ion channel complex or the voltage-dependent Ca channels. Conotoxin GIIIA seems to bind at the sites which are distinct from saxitoxin, but are functionally linked to the voltage-dependent Na channels. Conotoxins may be useful for the classification of Na channels in excitable cell membranes.

Adrenal Medulla↗
PubMed1990

[The serotype distribution of Campylobacter jejuni strains among gastroenteritis in hospitals over 7 year period in Tokyo].

Campylobacter jejuni strains isolated from gastroenteritis at 4 general hospitals of Tokyo Metropolitan during the period from 1981 to 1987 were serotype according to the slide agglutination test (TCK system) developed by the Tokyo Metropolitan Research Laboratory of Public Health. Two thousand four hundred seventy-nine strains isolated from sporadic cases among infants and children, 1,962 (78.5%) were typed by 33 typing sera numbered TCK 1 through TCK 33 and leaving 537 strains (21.5%) untypable. Out of the typable strains, 1,643 strains reacted with only single serum, while 319 strains reacted with 2 or more antisera. The most common serogroups included TCK 21, 20, 7, 1, 4, 23, 24, 10, 30 and 12. Out of the 1,250 strains isolated from sporadic cases among adults, 974 strains (77.9%) were typed and 276 strains were untypable. The most common serogroups were similar to those of infants and children. Serogroups TCK 1, 7, 4 and 21 were consistently the common serogroups every year during the 7 year study. Isolation frequency of serogroup TCK 30 have increased remarkably since 1986, while TCK 23, 14 and 9 have decreased.

Adult↗
PubMed1990

[A successful surgical case report of subaortic stenosis due to accessory mitral valve tissue associated with partial ventricular septal hypertrophy].

One-year- and ten-month-old male infant with subaortic stenosis due to the accessory mitral valve tissue associated with asymmetrical myocardial hypertrophy was treated successfully with surgery. Preoperative diagnosis of "discrete subaortic stenosis" was achieved by echocardiography and angiography. A 70 mmHg of preoperative pressure gradient from left ventricle through ascending aorta could be reduced to 25 mmHg by the operative excision of this accessory mitral valve tissue and partial resection of this septal hypertrophy. This patient was supposed to be complicated with the ventricular septal aneurysm according to the angiographic study, even though this aneurysm was not visualized at the time of the operation. According to our knowledge, only fifteen cases of stenosis due to accessory mitral valve tissue was reported. The pathological findings of the excised specimens of these anomalous tissue were presented and developmental genesis of this intracardiac anomalous tissues, perhaps based on the developmental anomaly of the primitive organ of the endocardial cushion, was discussed in this report.

Aortic Valve Stenosis↗
PubMed1990

[The development of a highly sensitive IgE immunoradiometric assay using monoclonal antibodies].

We have developed two-site immunoradiometric assay (IRMA) for quantitation of human serum IgE, using two different anti-IgE monoclonal antibodies which recognize different epitopes on IgE molecule. We obtained 25 different monoclonal antibodies classified seven groups, and then two different monoclonal antibodies were selected for bead coater and tracer after checking the titer and specificity of each antibody. IgE IRMA we developed here showed good performance in terms of specificity, sensitivity and reproducibility. No cross-reactivity to IgG, IgM and albumin in the level of normal range was observed. The sensitivity for IgE assay was 0.6 x 10(-3) IU/tube and measurable range was 0.01-20.0 IU/tube (0.5-10(3) IU/ml). Coefficient of variations of Intra assay were 2.2-4.3% and average recovery yield was 92.5-108%. Good correlations with Phadebas IgE PRIST and Pharmacia IgE RIA were obtained i.e., y = 1.12x-0.19 (r = 0.96) and y = 0.97x-5.9 (r = 9.7), respectively. These results indicate that the assay system will contribute much to the routine diagnosis for atopic allergy disease and parasitic infections.

Antibodies, Monoclonal↗
PubMed1990

[Bone marrow suppression in gynecological patients with malignant tumor treated with combination chemotherapy cyclophosphamide, pirarubicin and cisplatin].

We treated 14 patients with cyclophosphamide, adriamycin and cisplatin (CAP), and 16 patients with cyclophosphamide, Pirarubicin and cisplatin (CTP). Hematological changes in the peripheral blood were compared in the two groups to determine whether there was any difference in bone marrow suppression. 1) The lowest leukocyte counts were similar in the two groups. The leukocyte count reached its nadir at 11.6 +/- 2.1 days in the CTP group and at 15.1 +/- 2.8 days in the CAP group, a significant difference (p less than 0.01). 2) The leukocyte count recovered rapidly in the CTP group and was significantly higher (p less than 0.01) at 3 to 4 weeks than in the CAP group, and it returned to the pretreatment level in the CTP group in the fourth week. 3) The platelet count reached its lowest level in the second week in both groups. In the CTP group, it was significantly higher (p less than 0.01) than in the CAP group. 4) Reticulocyte count reached its lowest level in the first week in both groups, and then started increasing. 5) In the CTP group, a course of treatment was 28.0 +/- 2.3 days and it was 29.5 +/- 2.3 days in the CAP group. In 28% of the CPA group, it took 30 days or more for the leukocyte count to return to normal after one course, while none of the CTP group did the leukocyte count remain low for 30 days. These results show that CTP causes more rapid bone marrow suppression (particularly leukocytopenia) than CAP, does but that a recovery is more rapid with CTP. These CTP may be a better form of treatment than CAP.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1989

Leukoencephalopathy following treatment with carmofur: a case report and review of the Japanese literature.

A 53-year-old woman was treated with 5 courses of CAP treatment following operation for FIGO Stage Ia cancer of the ovary in September 1986. And in April 1987, she started an oral adjuvant chemotherapy with 400 mg/day of carmofur. In early June, she developed vertigo and dysarthia and was hospitalized. A CT scan showed low-density areas adjacent to both lateral ventricles, and an EEG revealed abnormally slow waves. She improved gradually after carmofur was discontinued and left the hospital in October 1987. There have been 24 reported cases of leukoencephalopathy because of carmofur in Japan, but the pathophysiological mechanism involved is not known. Since it is more common in women than in men, its incidence will probably increase in gynecological patients. Therefore, we must be on the lookout for central nervous system signs and symptoms in patients receiving adjuvant chemotherapy with carmofur.

Antineoplastic Agents↗
PubMed1989

[Effect of medroxyprogesterone acetate on side effects of CAP therapy in gynecological malignant tumors].

We concomitantly administered a large dose of medroxyprogesterone acetate (MPA) to gynecological malignant tumor patients undergoing CAP therapy (CAP). Hematological changes in the peripheral blood were compared between concomitant MPA patients and those not receiving MPA to examine the effect of MPA in reducing the marrow depression which is the major side effect of CAP. 1) Leukocyte count reached minimum at the second week of CAP in both groups. There was no significant difference in the count between the two groups. At the third week of CAP, the count improved to 84% of the pre-CAP level in patients receiving MPA and to 68% in those not receiving MPA, a significant difference (p less than 0.01). At the fourth week, leukocyte counts were 105% and 96% of pre-CAP levels, respectively. There was no difference between the two groups, but the leukocyte count returned to the pre-CAP level in the patients receiving MPA. 2) Platelet count showed changes similar to those in the leukocyte count. In patients receiving MPA, the count improved more rapidly within three weeks (118%, p less than 0.01), and was significantly higher at the fourth week (107%, p less than 0.05) than in patients not receiving MPA. 3) Reticulocyte count reached minimum in the first week, thereafter improving rapidly in both groups. No differences were noted between the two groups. 4) The periods needed for one course of CAP were 27.7 +/- 3.3 days in the patients receiving MPA and 29.5 +/- 3.7 days in the patients not receiving MPA, making for a significant difference between the two groups (p less than 0.05). These results show that MPA accelerates recovery from marrow depression caused by CAP. It is anticipated, therefore, that MPA will be helpful in the application of various chemotherapies which are expected to be frequently conducted in the future.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1989

[Carcinogenesis in familial polyposis coli].

The inherited cancer disease familial polyposis coli (FPC) provides an excellent model not only for studying tumor progression in colorectal cancer but also for elucidating molecular mechanism of carcinogenesis in general. This paper reviews recent remarkable progress in the molecular mechanism of tumorigenesis in FPC. Included in this review is information on the localization of the FPC major gene and several types of genetic alterations during the development of tumors. One of these genetic alterations is activation of oncogenes such as mutated ras genes and another is inactivation of tumor suppression genes such as loss of heterozygosity. The mutated FPC gene on chromosome 5 q would be expected to be an early event to initiate the requisite hyperproliferation for adenoma formation. Adenomas will have undergone several gene or chromosome mutations before reaching the fully malignant state.

Adenomatous Polyposis Coli↗
PubMed1988

A novel sodium channel inhibitor from Conus geographus: purification, structure, and pharmacological properties.

A novel toxin, tentatively named conotoxin GS (CGS), has been isolated from a marine snail, Conus geographus. CGS was found to exist as a single polypeptide chain, consisting of 34 amino acid residues, cross-linked by three disulfide bonds. Its amino acid sequence was shown to be Ala-Cys-Ser-Gly-Arg-Gly-Ser-Arg-Cys-Hyp-Hyp-Gln-Cys-Cys-Met-Gly-Leu-Arg- Cys-Gly - Arg-Gly-Asn-Pro-Gln-Lys-Cys-Ile-Gly-Ala-His-Gla-Asp-Val. In competition experiments, CGS inhibited the bindings of [3H]Lys-tetrodotoxin ([3H]Lys-TTX) and [3H]propionylconotoxin GIIIA to Electrophorus electricus electroplax membranes, with Ki values of 34 nM and 24 nM, respectively. The toxin inhibited the binding of [3H]Lys-TTX (1 nM) to rat skeletal muscle homogenates with an IC50 value of 880 nM but showed very little effect on this binding to the rat brain P2 fraction at 10 microM. These binding studies indicate that CGS belongs to the same group of Na channel inhibitors as TTX, STX (saxitoxin), and mu-conotoxins. Although CGS, like the mu-conotoxins, is a pharmacological probe for distinguishing between neuronal and muscle Na channel subtypes, the homology in the sequences of CGS and mu-conotoxins is very limited.

Amino Acid Sequence↗