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The Chinese soft-shelled turtle (Pelodiscus sinensis, Trionychidae, Testudines) has ZZ/ZW-type micro-sex chromosomes where the 18S-28S ribosomal RNA genes (18S-28S rDNA) are located. The W chromosome is morphologically differentiated from the Z chromosome by partial deletion and amplification of 18S-28S rDNA and W-specific repetitive sequences. We recently found a functional gene (TOP3B) mapped on the P. sinensis Z chromosome, which is located on chicken (Gallus gallus, GGA) chromosome 15. Then we cloned turtle homologues of 4 other GGA15-linked genes (GIT2, NF2, SBNO1, SF3A1) and localized them to P. sinensis chromosomes. The 4 genes all mapped on the Z chromosome, and 2 of them (SBNO1, SF3A1) were also localized to the W chromosome. Our mapping data suggest that at least one large inversion occurred between GGA15 and the P. sinensis Z chromosome, and that there are homologous regions in the distal portions of both the short and long arms between the Z and W chromosomes. W chromosomal differentiation in P. sinensis probably proceeded by the deletion of the proximal chromosomal region followed by 18S-28S rDNA amplification, after a paracentric inversion occurred at the breakpoints between the distal region of 18S-28S rDNA and the proximal region of SBNO1 on the Z chromosome. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Cancer vaccines represent a promising new strategy for immunotherapy against cancer, but their effects are insufficiently understood. The effect of heat treatment against mouse colon adenocarcinoma cell line (colon-26), and combined effects of heat treatment and immunizing host animals with heat treated colon-26 cell extracts were investigated. Heat treatment of colon-26 cells induced heat-shock protein 70 (HSP70), but not other HSP. Immunization of BALB/cJ mice with heat treated colon-26 cell extract, which was enriched in HSP70, elicited antitumour immunity against subcutaneously injected colon-26 cells. Furthermore, combination therapy of heat treatment and immunization with heat treated colon-26 cell extract significantly reduced tumour volumes compared with heat treatment alone. Similar immunization enhanced the cytotoxic activity of mouse splenic lymphocytes against untreated and heat treated colon-26 cells in an in vitro assay, as well as against heat treated allogenic mouse lymphoma cell line (YAC1). These findings suggest possible usefulness of heat treated cancer cell extract as a cancer vaccine, especially if given in combination with hyperthermia. [ABSTRACT FROM AUTHOR]

1. Major biliary conjugates of the male Wistar rat dosed orally with 2,4-dinitrotoluene (2,4-DNT) or 2,6-dinitrotoluene(2,6-DNT) were examined by hplc using potassium 2,4- dinitrobenzyl glucuronide (potassium 2,4-DNB- G), potassium 2,6-dinitrobenzyl glucuronide (potassium 2,6-DNB- G), pyridinium 2,4-dinitrobenzyl sulphate (pyridinium 2,4- DNB- S) and pyridinium2,6-dinitrobenzylsulphate (pyridinium2,6-DNB- S) as authentic compounds. Other metabolites were also examined by hplc. In addition, metabolites formed by incubation of potassium 2,4-DNB- G and potassium 2,6-DNB- G with rat intestinal microflora under nitrogen were examined by hplc. 2. Conjugates detected directly from bile following administration of 2,4-DNT and 2,6-DNT were 2,4-DNB- G and 2,6-DNB- G, which accounted for 35 0 and 51 5 % of the administered dose respectively. No peaks corresponding to pyridinium 2,4-DNB- S and pyridinium 2,6-DNB- S were detected in bile samples. 3. 2-Amino- 4-nitrotoluene,4-amino- 2-nitrotoluene,2,4-diaminotolueneand 4-acetylamino- 2-nitrobenzoic acid (0 02-0 12 % of the dose excreted in 24 h), in addition to the known metabolites 2,4-dinitrobenzyl alcohol (2,4-DNB), 2,4-dinitrobenzalde hyde and 2,4-dinitrobenzoic acid (0 09-0 14 %), were detected in ether extracts of bile of rat given 2,4-DNT. 2,6-Dinitrobenzylalcohol (2,6-DNB), 2-amino- 6-nitrotolueneand 2,6-dinitrobenzaldehyde(0 02-0 03 %), which are known metabolites, were detected in ether extracts of bile from rat given 2,6-DNT. 4. Potassium 2,4-DNB- G was transformed by the anaerobic incubationof rat intestinal microflora into 2,4-DNB, 4-amino- 2-nitrobenzyl alcohol and 2-amino- 4-nitrobenzyl alcohol. Potassium 2,6-DNB- G was transformed into 2,6-DNB and 2-amino- 6-nitrobenzyl alcohol by the anaerobic incubation. Time-course studies showed that 2,4-DNB, 4-amino- 2-nitrobenzyl alcohol, 2-amino- 4-nitrobenzyl alcohol and 2,6-DNB, 2-amino- 6- nitrobenzyl alcohol peaked at 30, 75, 120 and 10, 50 min respectively. 5. These results, together with previous findings, show that 2,4-dinitrobenzalde hyde and 2,6-dinitrobenzalde hyde, which are potent mutagens, are formed either by the hepatic metabolism of 2,4-DNB and 2,6-DNB formed by the intestinal metabolism of 2,4-DNBG and 2,6-DNB- G excreted in bile or by the direct hepatic metabolism of 2,4-DNT and 2,6-DNT. [ABSTRACT FROM AUTHOR]