The dynamics of pAL2-1 homologous linear plasmids in Podospora anserina

We have investigated the properties of the newly synthesized proton-pump inhibitor, 3-butyryl-8-methoxy-4-[(2-thiophenyl)amino]quinoline (YJA20379-6), on gastric mucosal proton-pump (H+/K+-ATPase) activity, gastric acid secretion and gastroduodenal lesions in experimental rats. YJA20379-6 markedly inhibited H+/K+-ATPase activity in rabbit isolated gastric mucosal microsomes, confirming its classification as a proton-pump inhibitor. The inhibitory efficacy of YJA20379-6 on the proton pump was approximately 14-times higher than that of omeprazole at pH 7.4. YJA20379-6 given intraduodenally had a potent inhibitory effect on gastric secretion in pylorus-ligated rats (ED50 22.9 mg kg(-1)) but was less active than omeprazole. Pretreatment of rats with YJA20379-6 dose-dependently protected the gastric mucosa from damage induced by water-immersion stress, indomethacin and absolute ethanol, and the duodenal mucosa from damage induced by mepirizole. Repeated administration of YJA20379-6 also dose-dependently accelerated the spontaneous healing of acetic acid-induced gastric ulcers. These results suggest that YJA20379-6 has potent anti-secretory and anti-ulcer effects which are exerted by suppression of H+/K+-ATPase activity in gastric parietal cells. YJA20379-6 might be useful for the clinical treatment of peptic ulcer diseases.     

Halves of epithelial somites and segmental plate show distinct muscle differentiation behavior in vitro compared to entire somites and segmental plate

Medial and lateral halves of the somite are known to differ with respect to their developmental fates: Cells from the medial half of the somite give rise to the epaxial muscle of the back and cells from the lateral half of the somite give rise to the skeletal muscles of the limbs and the ventrolateral body wall. To get a better insight into myogenic determination of somite hemispheres, isolated entire somites as well as medial and lateral parts of somites and of segmental plate from 2 day chick embryos were explanted in vitro. These parts of the paraxial mesoderm were also cocultured in contact with somite surrounding tissues such as neural tube lacking floorplate, neural tube including notochord-floorplate complex, and intermediate mesoderm, which were examined with respect to their muscle promoting or inhibiting influences. Skeletal muscle differentiation was monitored by the use of anti-myosin heavy chain antibody (MF20). It is shown that medial and lateral halves of segmental plate and epithelial somites are capable of undergoing myogenesis in the absence of axial organs. In contrast, cultures of intact segmental plate and epithelial somites from the same levels did not show muscle differentiation. Neural tube lacking floorplate promoted muscle differentiation in the medial halves especially of epithelial somites and also of segmental plate, but not in the lateral halves of the paraxial mesoderm at these levels. Intermediate mesoderm was found to inhibit muscle differentiation in medial and lateral halves of segmental plate and of epithelial somites. We further demonstrate that the arrangement of the myoblasts within tissue cultures is influenced by the presence or absence of axial organs.     

Use of monoclonal antibodies in diagnosis of paracoccidioidomycosis: new strategies for detection of circulating antigens

The precise diagnosis of paracoccidioidomycosis, in most cases, is established by direct methods and indirect immunological tests. The latter method is reliant on the identification of the host's humoral responses, which are usually impaired or absent in patients with severe juvenile forms of the disease and in immunocompromised patients. Determining disease activity or assessing treatment responses by measuring antibody levels is difficult, since antibody titer may remain elevated or persist at stationary levels, even in the presence of clinical improvement. Consequently, there is a need for alternative tests aimed at the identification of circulating antigens. A modification of the standard hybridoma production method was used to raise a panel of murine monoclonal antibodies (MAbs) against the yeast form of Paracoccidioides brasiliensis. Of these, MAb PIB, directed against an 87-kDa determinant, was used to develop an inhibition ELISA (inh-ELISA) capable of detecting as little as 5.8 ng of circulating antigen per ml of serum. Sera from 46 patients with paracoccidioidomycosis or other mycoses and sera from healthy individuals were evaluated by the inh-ELISA; overall sensitivity was 80.4% (37 of 46 paracoccidioidomycosis patients tested positive), and specificity compared with that of normal controls from areas of endemicity was 81.4%. The inh-ELISA detected circulating antigen in 100% of patients with the acute form of paracoccidioidomycosis and in 83.3 and 60% of patients with the chronic multifocal and unifocal forms of paracoccidioidomycosis according to the patients' clinical presentation. These results indicate that the inh-ELISA with MAb PIB is effective in the detection of circulating antigen and that this test may be useful for monitoring responses to treatment and establishing disease prognoses.