Biomedical subjects

A Ito

Publications and source records attributed to A Ito.

At least 235 records · Page 13Linked to original sources

PubMed1999

The role of the C-C chemokine receptor 2 gene polymorphism V64I (CCR2-64I) in sarcoidosis in a Japanese population.

A number of chemokines are produced by alveolar cells in the course of inflammatory reactions of sarcoidosis. C-C chemokine receptor 2 (CCR2) is a prominent receptor for the monocyte chemoattractant protein (MCP) group of C-C chemokines. A transition causing a valine to isoleucine substitution in transmembrane domain I of the CCR2 gene (CCR2-64I) that has a protective effect against the progression of human immunodeficiency virus-1 (HIV-1) disease has been described. To elucidate the role of this CCR2 polymorphism in sarcoidosis, we investigated the distribution of the CCR2-64I in 100 subjects with sarcoidosis (40.2 +/- 18.6 yr [mean +/- SD], 37:63 [male:female]) and 122 healthy control subjects (44.4 +/- 14.1 yr, 75:47). The distribution of the CCR2-64I allele was significantly different between subjects with sarcoidosis and healthy control subjects (p < 0.001). The presence of the CCR2-64I allele conferred a lower risk for the development of sarcoidosis (adjusted odds ratio = 0.369, 95% CI = 0.203 to 0.673). Our study suggests that this polymorphism may play a role in the pathogenesis of sarcoidosis, and further studies are needed to define the role of CCR2-64I.

Adolescent↗

PubMed1999

Hot water extract of bark of Nikko maple (Acer nikoense) induces apoptosis in leukemia cells.

In screening for antitumor constituents in traditional crude drugs, we used three cultured cell lines: mouse leukemia P388 cells, doxorubicin-resistant P388 cells and leczyme (catalytic lectin)-resistant P388 cells. The hot water extract (HWE) of the bark of Nikko maple (Acer nikoense) showed concentration-dependent inhibitory effects on the growth of these three cell lines. DNA fragmentation and morphological changes, accompanied by condensed and fragmented nuclei, were observed in the leukemia cell lines cultured with HWE of the bark of Nikko maple. Treatment with this HWE increased the expression of sialylated glycoconjugates on the apoptotic cells. These results suggest that HWE induces cell death via apoptosis in vitro.

Animals↗

PubMed1999

Establishment of an estrogen responsive rat pituitary cell sub-line MtT/E-2.

A rat pituitary tumor sub-line MtT/E-2 was established from a rat pituitary tumor cell line MtT/E. Its growth was found to depend on the presence of estradiol (E2) in culture media at 10(-13)-10(-9) M, whereas the original cell line MtT/E proliferated autonomously. The recently discovered PTTG (pituitary tumor transforming gene) is highly expressed in this cell line, although not regulated by E2. On the other hand, E2 induced c-myc and cyclin D1 proteins in MtT/E-2, which contains a lot (220+/-18 fmol/mg protein) of estrogen receptor demonstrated by RT-PCR analysis to be predominantly alpha type. MtT/E-2 secretes growth hormone which is, interestingly, regulated by retinoic acid and dexamethasone rather than thyroid hormones.

Animals↗

PubMed1999

Growth stimulation of a rat pituitary cell line MtT/E-2 by environmental estrogens in vitro and in vivo.

Endocrine disruptors are a diverse group of chemicals that alter the functions of the endocrine system. A large proportion of endocrine disruptors have estrogenic effects, thus are called environmental estrogens. In the present study, an estrogen (E2) responsive rat pituitary cell line, MtT/E-2, was employed to examine 1) the potency of several endocrine disruptors including bisphenol A (BPA), o,p'-DDD, methoxychlor, 1,2,3,4,5,6-hexachlorocyclohexane (HCH) and dibromoacetic acid (DBAA) in terms of E2 responsive pituitary cell growth; 2) whether BPA has estrogenic action in vivo causing the growth of MtT/E-2 cells grafted in rats. Binding assays showed the test chemicals were able to compete with 3H-E2 binding to the estrogen receptor (ER). The compounds also stimulated growth of MtT/E-2 cells at rates corresponding to their ER binding affinity. Their transcription activation of an (ERE)3-SV40-luciferase reporter in MtT/E-2 cells was comparable to their stimulation of cell growth, with the exception of HCH which showed little induction of cell growth but strong stimulation in ERE dependent transcription activation. MtT/E-2 cells were inoculated into ovariectomized female F344 rats treated with E2 or BPA. The first tumors were noted at day 22 in the E2 treated group, at day 25 in the highest dose of BPA group and at day 41 in the control group. These results suggest 1) that the growth assay with MtT/E-2 cells provides simple and sensitive test for detection of estrogenic activity of environmental chemicals; 2) that BPA has estrogenic potency to stimulate E2 responsive cell growth in vivo as well as in vitro.

Acetates↗

PubMed1999

Four new human renal cell carcinoma cell lines expressing globo-series gangliosides.

Clinicopathological studies revealed that monosialosyl galactosyl globoside (MSGG) and disialosyl galactosyl globoside (DSGG) expressed by renal cell carcinoma (RCC) are one of the biochemical indicator related to the metastatic potential. The present study examines the characteristics of four new human RCC cell lines and compares the expression of MSGG and DSGG among them using TLC immunostaining and flow cytometry. TOS-1 and TOS-2 were derived from metastatic subcutaneous tissues. TOS-3 and TOS-3LN were derived from the primary lesion and from metastatic lymph nodes respectively. Monolayer culture, light microscopy and electron microscopy of these cells showed that these cell lines were derived from RCC. TLC immunostaining and flow cytometric analysis revealed increased levels of MSGG in TOS-2 and TOS-3LN, and increased DSGG in TOS-1 and TOS-3LN. These cell lines would be useful for functional studies of globo-series ganglioside expressed by RCC.

Adenocarcinoma, Clear Cell↗

PubMed1999

Neurocysticercosis without detectable specific antibody.

A 19-year-old girl who had lived in India for five years until 1992 was admitted to Hokuto Hospital after general seizures which lasted for fifteen minutes. Cerebral magnetic resonance imaging (MRI) showed a ring-enhanced lesion of 6 mm in diameter in the right parietal lobe. She underwent surgical resection after diagnosis of the brain tumor. Histopathological examinations revealed that the resected tumor was a cysticercus of Taenia solium (T. solium), and we concluded that her seizures were caused by neurocysticercosis. Serological examinations by enzyme-linked immunosorbent assay (ELISA) and immunoblots to detect specific antibody against the glycoproteins of T. solium showed no detectable antibody response. The patient is under careful observation in our out-patient clinic with no medication.

Adult↗

PubMed1999

Differential serodiagnosis for cystic and alveolar echinococcosis using fractions of Echinococcus granulosus cyst fluid (antigen B) and E. multilocularis protoscolex (EM18).

Echinococcus granulosus cyst fluid and E. multilocularis protoscolex extract were fractionated by a single step of preparative isoelectric focusing, resulting in an antigen B-rich fraction (8-kD) and an Em18-rich fraction, respectively. The usefulness of both fractions for differential serodiagnosis of cystic (CE) and alveolar (AE) echinococcosis was evaluated by a large-scale immunoblot analysis on a battery of 354 serum samples. These included 66 from AE patients originating from four different endemic areas, 173 from CE patients originating from seven different endemic areas, 71 from patients with other parasitic diseases, 15 from patients with hepatomas, and 29 from healthy individuals. In an immunoblot with the antigen B-rich fraction, 92% (158 of 173) of the CE sera as well as 79% (52 of 66) of the AE sera reacted with the 8-kD subunit. No cross-reactivity occurred with any sera from patients with cysticercosis, other parasitic diseases, or with hepatomas, or from healthy controls. In an immunoblot with the Em18-rich fraction, all but two sera from AE patients (64 of 66, 97%) recognized Em18, and only nine of 34 CE sera from China reacted with it. All other (139) CE sera from six other countries were negative as were all (115) other non-echinococcosis sera. These findings indicate that antigen B (8-kD) is not species-specific for E. granulosus but is genus-specific for Echinococcus, and that the Em18 antigen is a reliable serologic marker for species-specific differentiation of AE from CE.

Animals↗

PubMed1999

Congenital transmission of Schistosoma japonicum in pigs.

Congenital transmission of Schistosoma japonicum in pigs was investigated by experimentally infecting sows at four weeks gestation (n = 3), 10 weeks gestation (n = 3), or a few weeks prior to insemination (n = 2). None of the piglets born to sows infected prior to insemination or in early pregnancy were found to be infected. However, all of the piglets (n = 26) born to sows infected at 10 weeks gestation were found to harbor schistosomes with S. japonicum eggs recovered from both their feces and livers. The findings show that congenital S. japonicum infection of pigs can occur if sows are infected during mid-to-late pregnancy and may have important implications not only for pigs but also for other mammalian hosts of schistosomes, including humans.

Animals↗

PubMed1999

[Hepatic listeriosis].

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Anti-Bacterial Agents↗

PubMed1999

[Hepatic actinomycosis].

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Actinomyces↗

PubMed1999

Esculetin (dihydroxycoumarin) inhibits the production of matrix metalloproteinases in cartilage explants, and oral administration of its prodrug, CPA-926, suppresses cartilage destruction in rabbit experimental osteoarthritis.

OBJECTIVE: To investigate the in vitro effects of 6,7-dihydroxycoumarin (esculetin) on the production of matrix metalloproteinases (MMP) in rabbit articular cartilage, and the in vivo effects of orally administered CPA-926, a prodrug of esculetin, on cartilage destruction in rabbit experimental osteoarthritis (OA). METHODS: In vitro studies were performed using rabbit articular cartilage explants. Esculetin 10-100 microM was added to cartilage explants in the presence or absence of interleukin 1alpha (IL-1alpha). Effects of esculetin on cartilage metabolism were assessed. Proteoglycan release into medium was determined by dye precipitation with 1,9-dimethylmethylene blue, synthesis of proMMP-1 (interstitial procollagenase) and proMMP-3 (prostromelysin 1) by Western blotting, and collagen degradation activity using FITC labeled collagen. In vivo experimental OA was induced in the knee joints of 15 Japanese adult white rabbits by partial lateral meniscectomy. Ten rabbits were orally administered 200 or 400 mg/kg/day of CPA-926 from the day of surgery for 14 days. The size of the macroscopic erosive area on the femoral condyle and tibial plateau was measured, and cartilage destruction was histologically evaluated. Collagenolytic activities in synovial fluid were measured using FITC labeled collagen as a substrate. RESULTS: In vitro, esculetin inhibited the IL-1alpha induced release of proteoglycan into the medium in a dose dependent manner. The collagenolytic activities in cartilage explant medium induced by IL-1alpha were also suppressed with the addition of 33-100 microM esculetin (p = 0.0209 at 33 and 100 microM, p = 0.0202 at 66 microM). Western blotting of cartilage explant medium showed a decrease in the levels of proMMP-1 and proMMP-3 in the medium by treatment with esculetin. In vivo: At 14 days after surgery, the femoral condyle and tibial plateau in the control group showed macroscopic erosions of cartilage. Compared with the control group, the rabbits treated with CPA-926 at the dose of 400 mg/kg exhibited reduction of the size of the erosive area on the tibial plateau (p = 0.009). Histological evaluation indicated protection against the development of destructive changes in the tibial plateau cartilage at a dose of 200 mg/kg (p = 0.0442) and 400 mg/kg (p = 0.0446) of CPA-926. CONCLUSION: These results indicate that esculetin inhibits matrix degradation in rabbit joint cartilage explants through the suppression of MMP synthesis, secretion, or activity. Prophylactic administration of its prodrug, CPA-926, appears to provide some protection against cartilage destruction in a short term rabbit experimental OA model.

Administration, Oral↗

PubMed1999