Purification of Mesodermal-inducing Substances from Carp Swim Bladders I. Extraction and Isoelectric Focusing

Mesodermal-inducing substances were isolated from the swim bladders of carp ( Carassius auratus ). These substances, extracted with 8 M urea, can induce the development of early gastrula ectoderm cells of newts into mesodermal tissues, such as muscles, notochords, mesenchyme, renal tubules, and so on, to a high degree. Isoelectric focusing was used to isolate them as a first purifying step, and five component parts with different pH ranges were obtained. Each part was tested for mesodermal-inducing activity. On the basis of the extent and percentage of the induced tissues, two of them (parts C and D with pH ranges 6.0 to 7.0 and 7.0 to 9.0, respectively) were found to have high inducing activity, and the others had lower activity. The substances present in part C showed only low mesodermal-inducing activity, when diluted with gamma-globulin 100-fold. Apparently highly active mesodermal-inducing substances exist in the two parts C and D.     

Potential fragmentation and loss of thermal habitats for charrs in the Japanese archipelago due to climatic warming

1. The upper thermal limits of the present distributions of two charr species, Dolly Varden, Salvelinus malma , and white-spotted charr, S. leucomaenis , in streams of the Japanese archipelago were examined using groundwater temperature as an index of thermal condition. The lower limits of the altitudinal distributions of Dolly Varden and white-spotted charr were delineated, respectively, by 8 and 16 °C groundwater isotherms.
2. The potential impact of future climatic warming on the geographical distribution, habitat extent and population fragmentation of each species was predicted at both the full archipelago and individual catchment levels.
3. For Dolly Varden, analysis at the full archipelago level indicated a loss of 27.6, 67.2, 79.6 and 89.6% of the current geographical range, respectively, for a 1, 2, 3 and 4 °C increase in mean annual air temperature. The present distribution area of white-spotted charr would likewise reduce by 4.1, 20.5, 33.8 and 45.6%, respectively.
4. Based on the analyses of three individual catchments, one for Dolly Varden and two for white-spotted charr, the lower habitat boundaries for the two charr species could be expected to rise increasingly to higher elevations in each catchment as warming proceeded. As a consequence, there would be large reductions in mean habitat area, with increasing habitat fragmentation followed by localized extinctions of the two species.     

Antisporozoite Antibodies with Protective and Nonprotective Activities: In Vitro and In Vivo Correlations Using Plasmodium gallinaceum, an Avian Model

ABSTRACT. A correlation was observed between in vivo and in vitro activity of six monoclonal antibodies (mAb) against the major circumsporozoite protein of the avian malaria Plasmodium gallinaceum as follows. (1) Two mAb were protective, totally abrogating sporozoite infectivity to chicks, its natural host, in vivo; they caused 100% inhibition of sporozoite invasion (ISI) in vitro to SL-29 chicken fibroblasts and intense ISI to cultured chicken macrophages, as well as inhibited the exoerythrocytic development of sporozoites taken up by macrophages, the initial cell host of P. gallinaceum sporozoites. (2) Two mAb were partially protective in that they reduced sporozoite infectivity to chicks, caused partial ISI to SL-29 and macrophage cells and partial inhibition to the exoerythrocytic development of sporozoites in macrophages in vitro. (3) Two mAb were totally inactive in vivo although they both bound to the sporozoite antigens as detected by indirect immunofluorescence, western blot, and ELISA; they both failed to induce ISI or inhibit the exoerythrocytic development in macrophages. The possible participation of macrophages as the initial cell type involved in sporozoite destruction in the presence of anti-circumsporozoite antibodies is discussed.     

Purification and Characterization of Isocitrate Lyase from Ethanol-grown Euglena gracilis

Isocitrate lyase was purified to homogeneity from ethanol-grown Euglena gracilis. The specific activity was 0.26 μmol/min/mg protein. The molecular mass of the enzyme was calculated to be 380 kDa by gel filtration on a Superose 6 column. The subunit molecular mass of the enzyme was 116 kDa as determined by SDS-polyacrylamide gel electrophoresis. These results showed that the native form of this enzyme was a trimer composed of three identical subunits. The pH optimum for cleavage and condensation reactions was 6.5 and 7.0, respectively. The K_m values for isocitrate, glyoxylate and succinate were 3.8, 1.3 and 7.7 mM, respectively. Isocitrate lyase absolutely required Mg for enzymatic activity. This is the first report of the purification of isocitrate lyase to homogeneity from Euglena gracilis.     

Common Epitopes In the Circumsporozoite Proteins of Plasmodium Berghei and Plasmodium Gallinaceum Identified By Monoclonal Antibodies to the P. Gallinaceum Circumsporozoite Protein

ABSTRACT. Monoclonal antibodies that react with the circumsporozoite protein of the avian malaria Plasmodium gallinaceum sporozoites also reacted with circumsporozoite protein of the rodent malaria Plasmodium berghei. Two types of reactivity were identified: 1) two monoclonal antibodies reacted with P. berghei sporozoite protein by enzyme-linked immunosorbent assay, Western blot and indirect immunofluorescence antibody, 2) six other monoclonal antibodies reacted with P. berghei sporozoites by ELISA and Western blot only. We studied whether these differences could be explained by reactivity in enzyme-linked immunosorbent assay with different P. berghei circumsporozoite peptides. Although all P. gallinaceum monoclonal antibodies reacted with the P. berghei repeats, the first group reacted with a conserved peptide sequence, N1, whereas the second group did not. These results suggest that circumsporozoite proteins from P. gallinaceum and P. berghei share common epitopes. the biological significance of our finding is not yet clear. Indeed, the cross-reactive monoclonal antibodies giving a positive indirect immunofluorescence antibody with the P. berghei sporozoites only caused a borderline effect on the living P. berghei parasites in vitro as measured by inhibition of sporozoite infectivity.     

Potential fragmentation and loss of thermal habitats for charrs in the Japanese archipelago due to climatic warming

1. The upper thermal limits of the present distributions of two charr species, Dolly Varden, Salvelinus malma , and white-spotted charr, S. leucomaenis , in streams of the Japanese archipelago were examined using groundwater temperature as an index of thermal condition. The lower limits of the altitudinal distributions of Dolly Varden and white-spotted charr were delineated, respectively, by 8 and 16 °C groundwater isotherms.
2. The potential impact of future climatic warming on the geographical distribution, habitat extent and population fragmentation of each species was predicted at both the full archipelago and individual catchment levels.
3. For Dolly Varden, analysis at the full archipelago level indicated a loss of 27.6, 67.2, 79.6 and 89.6% of the current geographical range, respectively, for a 1, 2, 3 and 4 °C increase in mean annual air temperature. The present distribution area of white-spotted charr would likewise reduce by 4.1, 20.5, 33.8 and 45.6%, respectively.
4. Based on the analyses of three individual catchments, one for Dolly Varden and two for white-spotted charr, the lower habitat boundaries for the two charr species could be expected to rise increasingly to higher elevations in each catchment as warming proceeded. As a consequence, there would be large reductions in mean habitat area, with increasing habitat fragmentation followed by localized extinctions of the two species.     

Karyotype analysis in South American species of Myrtaceae

In Myrtaceae (Myrteae), the diploid chromosome number 2 n  = 2 x  = 22 is the most common, although variations of ploidy level occur, with some triploid (2 n  = 3 x  = 33) and tetraploid (2 n  = 4 x  = 44) records. Karyotype details in this group are scarce because the chromosomes are small (< 2 μm). In this work, we carried out a karyotypic analysis of 15 species of Myrtaceae grouped in different subtribes and genera. Measurements of chromosome length (long arm, L ; short arm, S ) were taken and several karyotypic parameters were calculated for each species. The karyotypes in fleshy-fruited taxa (Myrteae) were more varied than in the other previously analysed dry-fruited group ( Eucalyptus , Eucalypteae), in which the chromosomes were exclusively metacentric.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 155 , 571–580.     

Chromosome numbers in Brazilian species of Crotalaria (Leguminosae, Papilionoideae) and their taxonomic significance

Chromosome numbers were counted for 23 species of Crotalaria native to Brazil. Among these data there were new counts for 15 taxa, and some confirmed previous reports or represented numbers that were different from those cited previously. The chromosome numbers most frequently found were 2 n  = 16 and 2 n  = 32. Only C. incana L. had 2 n  = 14 and C. tweediana Benth. had 2 n  = 54. The counts 2 n  = 32 and 54 were found in species of section Calycinae and 2 n  = 16 and 14 in species of section Chrysocalycinae . The data revealed the importance of chromosomal parameters in the characterization of sections Calycinae and Chrysocalycinae in Brazil. We discuss the systematic significance and evolutionary aspects for the genus, comparing the results with the two sections that are native in Brazil.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 271–277.