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Aspicilia goettweigensis is a poorly known species from xerothermic siliceous rocks in Europe. It is considered to be common in the Czech Republic and it is new to Hungary and Russia. The main diagnostic character is formation of cracked, popcorn-like, areoles in the central parts of the thalli. Analysis of nrITS sequences revealed its close relationship to Aspicilia subdepressa and A. volcanica. TLC revealed stictic acid in analysed A. goettweigensis samples. A key to non-lobate Aspicilia with stictic acid known from Europe is provided.

This study explored whether adding a haptic interface (that provides users with somatosensory information about virtual objects by force and tactile feedback) to a three-dimensional (3D) chemical m ...

Morphological variation in Sporodictyon is scrutinized in an effort to reconcile it with monophyletic groups based oil molecular evidence. Molecular data (nucITS, nucLSU, RPBI) are investigated ...

Recent molecular phylogenetic analyses and morphological Studies have shown that it is necessary to revise the present morphology-based generic delineation of the lichen family Verrucariaceae in or ...

Side effects associated with current immunosuppressive therapy complicate the use of islet transplantation as a treatment for type 1 diabetes. Multipotent mesenchymal stromal cells (MSCs) have demonstrated immunomodulatory activity. The purpose of this study was to investigate whether a murine stromal cell line affects graft rejection in a fully major histocompatibility complex (MHC)-mismatched islet transplant model. We show that stromal cells have an inhibitory effect on T cell proliferation in vitro, and that they slow down the rejection of allogeneic islets. These findings indicate a possibility to use MSCs as a treatment to prolong the survival of islet grafts.

In a previous three gene phylogeny study (nuITS rDNA, nuLSU rDNA and RPB1 region A-D) a well supported clade, most closely related to Verrucaria rupestris and also close to Sporodictyon and Atla, was found. Here this clade is identified as Henrica. A phylogeny of these genera based on the nuITS rDNA is supplied, and also a key to crustose species in Verrucariaceae with large, brown muriform spores. Based on material from northern Europe, Henrica is emended to include H. theleodes and H. melaspora, both new combinations in the previously monotypic genus. Verrucaria theleodes and V. scotinospora are lectotypified.

Bayesian inference analyses of nuclear LSU rDNA sequences showed Verrucariales and Eurotiales to form the sistergroup of Mycocaliciales. A more detailed analysis of ITS rDNA sequences showed Sphinctrinaceae to be embedded in Mycocaliciaceae. Mycocaliciales contain two major lineages. Intron occurrence and phylogeny was partly congruent with the ITS-based phylogeny. Chaenothecopsis is paraphyletic with respect to Phaeocalicium, Mycocalicium, Sphinctrina and Stenocybe. Some morphological features traditionally used for characterising Chaenothecopsis and other genera in Mycocaliciales, such as ascus apex structure and stalk anatomy, were found to be homoplasious, while others, such as spore septation, intron distribution and nutritional biology, were consistent with major clades in the analysis. Within the two major clades of Mycocaliciales some subclades are strongly supported and well characterized by anatomical, nutritional and intron features.

Background: The IgG antibody response in type I diabetic patients, transplanted with fetal pig islet-like cell-clusters, was investigated using purified immunoglobulin G (IgG) fractions from sera collected 7 to 9 yr after transplantation. From our earlier studies, we knew that the immunological specificities of xenoreactive IgG1 and IgG2 antibodies are different, and that IgG1 antibodies, in contrast to the IgG2 population, are mainly directed against non-Galα1,3Gal epitopes. In this study our goal was to establish whether xenoreactive IgG1 and IgG2 antibodies react with pig islet cells and, if so, to identify the target cell type, the biological function as well as the specificity of such antibodies for islet cell antigens. Sera from xenotransplanted patients were compared with those of patients with diabetes, selected for high titres of islet-cell specific autoantibodies. Methods: IgG antibody fractions from patient sera were purified on a protein G column. Surface expression of target antigens was studied using flow cytometry as well as immunofluorescence microscopy. The biological function of islet-cell reactive sera was tested using antibody dependent cellular cytotoxicity with both xenogeneic adult pig islet cells and allogeneic human islet cells as targets. Antibody specificity was assessed using 2D Western blots with both fetal and adult pig islet as well as human islet cell antigenic preparations. Results: Some of the diabetic patients, who have been transplanted with xenogeneic fetal pig islet cells, continue to produce xenospecific IgG1 and IgG2 antibodies for 7 to 9 yr post-transplantation. A separate analysis of IgG1 and IgG2 antibodies showed that IgG1 antibodies react with pig islet β cells, whereas IgG2 antibodies mainly react with non-endocrine pig cells. Such antibodies are xenospecific, as they were found to mediate antibody-dependent cellular cytotoxicity of adult pig, but not human islet target cells. The reverse was true for antibodies from non-transplanted diabetic patients with high titres of autoantibodies against β cells. Fluorescence analysis as well as 2D gel Western blots revealed that the reactivity was variable between patient samples, indicating that target antigens for non-Galα1,3Gal-specific antibodies are heterogeneous. Conclusion: Thus, xenotransplantation of diabetic patients induces islet-β cell reactive xenospecific IgG1 antibodies, which are biologically active and can mediate antibody-dependent cellular cytotoxicity of pig islet cells.

0.01 vs. controls). In untreated control rats, xenoreactive antibody (IgM, IgG) levels decreased immediately after PE, but their levels rapidly returned to normal. In rats treated with DSG or DSG + Lip-Cl2MDP, the IgM levels remained low during the observation period. Immunohistochemistry showed that macrophage infiltration into the graft was suppressed in Lip-Cl2MDP-treated groups at the time of rejection. Our results demonstrate that sustained suppression of antibody levels can be achieved by PE in combination with DSG and xenograft survival is further prolonged in macrophage-depleted C6- rats. These findings suggest that strategies targeting antibody and macrophages may be useful in prolonging xenograft survival.

Chaenotheca phaeocephala and C. subroscida have been characterized by differences in their morphology and ecology. They are, however, morphologically plastic and sometimes seem to intergrade. It has been suspected that the differences in morphology between these two taxa could possibly be phenotypic and caused by their occurrence in different habitats and/or by the association with different photobionts. To test if there is a genetic difference between the species ITS1–5.8S-ITS2 rDNA sequences of six specimens of the mycobiont of C. phaeocephala and five of C. subroscida were compared. Further the ITS1–5.8S-ITS2 rDNA sequences of the photobiont of one specimens of C. phaeocephala and six of C. subroscida were compared to each other and to other species of Trebouxia. The mycobiont sequences of both C. phaeocephala and C. subroscida were monophyletic, substantially different and the groups had strong supports. They also proved to be associated with different Trebouxia species, C. phaeocephala with T. arboricola and Chaenotheca subroscida with T. jamesii. The morphologically based concepts of C. phaeocephala and C. subroscida thus not merely represent phenotypic variation but also are associated with considerable genetic differences in the extremes of the ITS1–5.8S-ITS2 rDNA region.

Suppression of T cells results in long-term survival of mouse heart xenograft in C6-deficient rats.

We have monitored the humoral immune responses of 10 type I diabetic patients, xenotransplanted with fetal porcine islet-like cell clusters for up to 8 years after xenotransplantation. We investigated the immunoglobulin subclass distribution as well as specificity differences of xenoreactive antibodies. Hemagglutintion tests, using pig erythrocytes, showed that some patients maintained higher titers of xenoreactive IgM antibodies during the entire follow up period, compared with pretransplant levels. In microcytotoxicity tests all but one patient tested showed higher than pretransplant levels of cytotoxic antibodies against pig peripheral blood mononuclear cells (PBMC) 6-8 years after transplantation. Levels of Gal alpha 1,3Gal specific antibodies, were also high. Antibody dependent cellular cytotoxicity (ADCC) activity against a Gal alpha 1,3Gal expressing human B cell line was detected in four patients while ADCC reactivity against adult pig islet cells was detected in only two patients, 6-8 years after transplantation. Immune sera collected 30 days and 1 year after transplantation showed positive staining of adult pig islet cells in fluoromicroscopy whereas sera from later time points did not. Western blot experiments showed that some patients had IgG1 antibodies reactive against epitopes on pig cells other than Gal alpha 1,3Gal, while xenoreactive IgM and IgG2 antibodies mainly reacted with Gal alpha 1,3Gal-containing epitopes as shown by absorption experiments. These results show that patients continue to produce higher than pretransplant levels of IgM and IgG2 xenospecific antibodies against Gal alpha 1,3Gal for extended time periods following xenotransplantation. Some patients also produce xenoreactive IgG1 antibodies directed against non-Gal alpha 1,3Gal epitopes.

A synopsis of 42 species is given. Thirteen of the species are tropical to warm temperate, seventeen of the species are antitropical and mainly occur in the mountainous areas. Calicium lutescens, C ...

Lack of antibody production against Hanganutziu-Deicher (H-D) antigenswith N-glycolylneuraminic acid in patients with porcine exposure history[In Process Citation]

Pig islet xenograft rejection is markedly delayed in macrophage-depletedmice: a study in streptozotocin diabetic animals [In Process Citation]

The purpose of this study was to investigate the effect of macrophage depletion, using liposome-encapsulated dichloromethylene diphosphonate (Lip-Cl2MDP), on delayed xenograft rejection (DXR) in the guinea pig-to-C6-deficient rat heart transplantation model. In this model, hyperacute rejection does not occur, but, in untreated recipients, xenografts are still destroyed by DXR within 1-2 days. Graft survival was 68 +/- 8.4 h in splenectomized control rats, 77 +/- 16.3 h with Lip-Cl2MDP alone, 99 +/- 10.4 h with deoxysperguarlin (DSG; P < 0.01 vs. controls), and 127 +/- 19.4 h with Lip-Cl2MDP plus DSG (P < 0.01 vs. DSG alone). Treatment with DSG alone or in combination with Lip-Cl2MDP resulted in significant reductions in serum IgM levels at rejection. Immunohistological studies showed that Lip-Cl2MDP alone or in combination with DSG reduced infiltration of grafts by both EDI + and ED2 + macrophages. These experiments support the concept that macrophages play an important role in DXR and suggest that strategies targeting macrophages may be useful in controlling DXR.

Insulin resistance and increased demand for insulin secretion occur after successful pancreas transplantation. To investigate the potential effects of immunosuppression and pancreas transplantation on fasting beta-cell function, we studied fasting proinsulin and 32,33 split proinsulin secretion cross-sectionally and longitudinally in segmental pancreatic graft recipients (SPx, n = 18); in whole-pancreas graft recipients (WPx, n = 13); in nondiabetic kidney transplant recipients (Kx, n = 14) and in normal subjects (Ns, n = 14). Basal insulin secretion rates were significantly increased in SPx 15.8 (1.7), WPx 24.4 (4.5) and Kx 22.1 (2.1) vs Ns 9.7 (1.6) pmol min(-1) l(-1), p < 0.05, mean (SEM). Total proinsulin, intact proinsulin and 32,33 split proinsulin concentrations were significantly higher in all the transplanted groups than in normal subjects (p < 0.05), whereas the total proinsulin to C-peptide ratio and the 32,33 split proinsulin ratio were higher in SPx than in WPx, Kx and Ns (< 0.05). In the longitudinal study, beta-cell function in terms of proinsulin secretion remained stable for 1 year. In conclusion, fasting glucose homeostasis in pancreas-kidney transplant recipients is obtained at the expense of increased proinsulin secretion and increased insulin secretion rates, primarily induced by immunosuppression. In segmental pancreas graft recipients, increased fasting proinsulin and 32,33 split proinsulin relative to the number of beta-cells transplanted indicate more stress on the residual beta-cell and therefore higher secretory demand than in whole pancreas transplant recipients.

Porcine fetal endocrine pancreatic tissue was placed under the kidney capsule in a diabetic renal transplant patient. In a core-needle kidney biopsy specimen obtained 3 weeks after transplantation, clusters of epithelial cells were identified in the subcapsular space. The ultrastructural and immunocytochemical features of these cells were typical of pancreatic islet cells. Some cells stained positively for insulin; others stained positively for glucagon, somatostatin or chromagranin A. There were well-defined cytoplastic storage and transport granulae that indicated hormone synthesis. The ultrastructural findings provide further evidence that porcine cells can survive after transplantation to humans.

Efficacy of immunosuppressive drugs in islet xenotransplantation: A study in the pig to rat model.

The immune antibodies produced in diabetic patients by the challenge of the immune system with pig fetal islet-like cell clusters were analyzed in regard to carbohydrate specificity. Binding of antibodies to total non-acid glycosphingolipid fractions from pig aorta and pig erythrocytes was tested in a radioimmunoassay using native serum, serum adsorbed on solid phase columns with either Galα(1,3)Gal specificity or Galα(1,4)Gal specificity. The eluates from the columns were also tested. Adsorption on the Galα(1,3)Gal column completely eliminated binding both to aortic and erythrocytic fractions, while adsorption on the Galα(1,4)Gal column reduced the binding but did not eliminate it. This can be explained by the presence of at least two kinds of antibodies, one recognizing terminal α-linked galactose and the other recognizing the Galα(1,3)Gal epitope, thus requiring a disaccharide for binding. A total non-acid glycolipid fraction was prepared from porcine fetal islet-like cell clusters and tested against immune serum from a patient transplanted with such cells. Binding was only found to the pentaglycosylceramide region with an identical retention time as the “linear B” antigen for pig aorta. This indicates the presence of that structure also in porcine fetal islet-like cell clusters.

The natural anti-Gal antibody seems to create a major obstacle for discordant xenotransplantation in humans. Anti-Gal, which is produced in large amounts in humans (1% of circulating IgG), interacts specifically with the carbohydrate structure Gal alpha 1-3Gal beta 1-4Glc-NAc-R (termed the alpha-galactosyl epitope). This epitope is present in large amounts on porcine cells, as well as on cells of other nonprimate mammals (1 x 10(6) to 35 x 10(6) epitopes/cell). The interaction of anti-Gal with alpha-galactosyl epitopes on the xenograft was found to mediate the immune destruction of discordant xenografts. In the present study, the human immune response to alpha-galactosyl epitopes on xenografts was assessed by measuring changes in anti-Gal titers and affinity in sera of diabetic patients transplanted with fetal porcine islet cell clusters. The activity of this antibody was assessed by a hemagglutination assay with RBC, by ELISA with mouse laminin as a solid-phase antigen, and by equilibrium dialysis with the radiolabeled free haptenic form of the alpha-galactosyl epitope, i.e. [3H]Gal alpha 1-3Gal beta 1-4GlcNAc. All assays revealed a marked increase in anti-Gal activity after transplantation. The increase in anti-Gal titers ranged between 8- and 64-fold. A similar increase was observed in the binding of free alpha-galactosyl epitopes to anti-Gal, as assayed in equilibrium dialysis. Immunoglobulin concentration did not increase after transplantation, suggesting that the observed increase in anti-Gal activity is the result of a specific immune response against alpha-galactosyl epitopes on the xenograft. The elevation in anti-Gal activity was observed in all three immunoglobulin classes and the highest activity was found within the IgG class. Analysis of IgG binding to fixed porcine endothelial cells suggested that most of the observed increased activity against these cells in transplanted patients may be attributed to the elevation in anti-Gal activity.

In the commercially available intravenous formulation of Cyclosporin A (Sandimmun), polyoxyethylated castor oil (Cremophor EL) is used as a solubilizing agent. We have recently reported that the acute nephrotoxic effect of this preparation was alleviated by replacing Cremophor EL with a soybean oil-based fat emulsion in a rat model. To further explore the potential of fat emulsions as carriers for cyclosporin A, data on the in vivo pharmacokinetics and tissue distribution are required. In this study in pigs, the pharmacokinetics of soybean oil-cyclosporin A was compared to that of Sandimmun. The two formulations seemed bioequivalent, as there were no significant differences in the systemic clearances, volumes of distribution or elimination half-lives. Moreover, the tissue distributions of soybean oil-cyclosporin A and Sandimmun were compared in rats. These studies also included two additional lipid-based carriers: one based on iodized ester of poppy seed oil and the other on a liposomal preparation. The tissue distributions were found to be similar regardless of the carriers used. Fat emulsion carriers seem to offer possibilities for preparing better tolerated intravenous formulations of cyclosporin A while maintaining the same characteristics concerning pharmacokinetics and tissue distribution.

The immunological specificity of antibodies formed as a result of xenotransplantation of fetal porcine islet-like cell clusters to diabetic patients was characterized. High titer increases were recorded against porcine cells, solubilized membrane fractions of porcine cells, and purified MHC class I antigens. However, titer increases were also noted against ssDNA and dsDNA and against pig thyroglobulin but not against actin, myoglobin, or haptenated BSA. Antibody titers against tetanus toxoid were unaffected. The reactivity against porcine RBC could be completely blocked by absorption with pig thyroglobulin. Since pig thyroglobulin contains the galαl-3gal antigen, the reactivity against RBC was most probably mainly due to antibodies against this oligosaccharide epitope. The reactivity against porcine mononuclear cells was only partially absorbed by pig thyroglobulin, indicating a heterogeneity of the clonal response. These conclusions were substantiated by data showing that the antigenic determinants on pig thyroglobulin were completely destroyed by treatment with α- but not with β-galactosidase. Further studies showed that immune reactivity against pig RBCs, platelets, islet-cells, endothelial cells and pig MHC class I molecules, caused by xenoimmunization, was almost completely blocked by either absorption of antibodies on a column of Sepharose beads coated with galα1-3gal or by pretreatment of the antigen fractions with α-galactosidase. Western blot experiments revealed that both the natural and xenoimmune antibodies reacted with a large number of different glycoproteins. There was no difference in heterogeneity of the response when comparisons were made between pre-and posttransplantation sera, nor was there any difference of patterns caused by IgM or IgG antibodies. Absorption studies revealed that this epitope was present in a large number of different glycoproteins, a conclusion verified by staining with the eluate from a thyroglobulin-immunosorbent column or with the eluate from the galα1-3gal-coupled Sepharose column. Our findings demonstrate that the xenoimmune response is mainly directed against oligosaccharide residues and that there is a limited clonal heterogeneity of antibodies in xenografted patients. There was no direct evidence of reactivity against any porcine proteins nor of specific immunization against porcine MHC peptides. The data form a basis for a future understanding of means to cope with and prevent the rejection of xenogeneic islet cells in man. We also suggest, based on the specificity found in xenoimmunized patients sera, that a major part of naturally occurring antibodies might be specifically reactive with carbohydrate antigens.

Porcine fetal islet-like cell clusters (ICC) were transplanted to 10 renal transplant patients suffering from long-standing type I diabetes. Since they had renal grafts, they were given immunosuppression with cyclosporine, prednisolone and azathioprine. Eight patients had the ICC injected intraportally and two had the ICC placed under the renal graft capsule. At the time of the xenotransplantation, ATG or 15-deoxyspergualin was given as an adjunct. Evidence of engraftment, as reflected by excretion of small amounts of porcine C-peptide into the urine, was observed in four of the patients. In all patients, irrespective of the type of immunosuppression given and whether graft function was established or not, specific xenoantibodies were formed. Titer increases in lymphocytotoxic antibodies occurred after 10 to 14 days with peak reactivity after 30 to 50 days. High titers of ADCC activity measured against porcine lymphoblasts were found in all patients. Titers were maintained at a high level for at least 100 days. Antibody titers were monitored against pig lymphocytes, erythrocytes and against pig membrane antigens solubilized from peripheral blood mononuclear cells, platelets and erythrocytes. Both IgM and IgG antibodies were formed with identical kinetics. There was no increase in the titers of alloantibodies, as evidenced by panel-reactive lymphocytotoxic antibodies. In all patients an increase in titers of isohemagglutinins was recorded, especially against blood group B antigens. Absorption studies showed that xenoreactivity present in healthy individuals could not be blocked by absorption with human RBC. However, in all transplanted patients, xenoreactivities against pig antigens were inhibited by absorption with human RBC, in particular with B-type RBC. These data show that the increase in isohemagglutinins was probably due to cross-reactivity with xenogeneic antigens. Using an ELISA assay, increased antibody titers were also recorded against purified pig MHC class I antigens. However, as is shown in the accompanying paper (next issue), these antibodies were probably not directed against protein determinants on the MHC molecules but rather against glycosylated side chains of these molecules.

Serum samples were collected from four diabetic patients who had received intraportal injections of pig fetal islet-like cell clusters (ICC). The binding of IgM and IgG antibodies to glycosphingolipid antigens prepared from different pig organs and separated on thin layer plates was investigated in pre- and posttransplant serum samples. Both IgM and IgG antibodies in the pretransplant serum samples bind to several glycolipid fractions from the tri-, tetra- and pentasaccharide regions but also to compounds with longer carbohydrate chains. In the posttransplant serum samples stronger binding, compared to the pretransplant samples, was noted for both Ig-classes. Strong binding was seen in the pentasaccharide region known to contain the “linear blood group B” structure Galαl-3Galβl-4GlcNAcβl-3Galβl-4Glcβl-lCer. There was no convincing evidence of the I recognition of new specificities. Adsorption of a patient serum to a Synsorbcolumn with Galαl-3Gal specificity did not grossly change the binding pattern of the IgG antibodies in the effluate. However, the eluate from the column showed strong binding to the “linear B” compound but also to glycolipids with longer carbohydrate chains presumably with the same terminal epitope. Identification of these are in progress. The human natural anti-pig antibodies against carbohydrate antigens expressed on pig cells seem to detect a rather limitted number of epitopes. The “linear B” structure appears to be one major target. However, other structures may also be targets for xenoreactive antibodies. Immunisation with pig cells does not seem to initiate antibody production against new carbohydrate epitopes but leads to an increased production against the existing ones.

Both a coelomycetous and a hyphomyeetous anamorph were obtained in axenic sporc cultures of the myeobiont of Chaenotheca deludens (Coniocybaceae. Caliciales). Coelomyeetous anamorphs have previously not with certainty been reported from Chaenorheca. Similarities between the coelomycetous Chaenotheca anamorph and the Asrerophoma anamorph of Chaenorhecopsis suvonica were noted. Thc conidia from the hyphomycetous anamorph germinated easily to produce new subcultures and it is suggested that conidia may also function in asexual reproduction in the field.

An anamorph of Chaenothecopsis viridireagens occurring in the field is reported. It is coelomycetous and the conidiomata are formed on stalks which often branch to form tree-like complexes. Similar structures are formed in axenic cultures. This anamorph is compared to anarnorphs of other Chaenothecopsis species. In cultures a hyphomy-cetous anamorph was also formed.

Seventeen species of Chaenothecopsis are reported from the Russian Far East. Chaenothecopsis amurensis, C. asperopoda, C. golubkovae and C. ussuriensis are described as new. C. brevipes is new to Eurasia and C. haematopus, C. koerberi and C. rubescens are new to Asia. A key, descriptions and illustrations of the species, habitat ecology and distribution are presented.

The type of Opegrapha pyrenocarpoides is conspecific with Tylophorella polyspora, and the new combination T. pyrenocarpoides is made. Tylophorella has been placed in Caliciales s. lat., but shows similarities both to Pyrenulales and Arthoniales. T. pyrenocarpoides is reported new to Africa.

The crustose lichen flora of fifteen areas in boreal coniferous forests from southern Sweden to Lapland was surveyed. Many of these areas are included in a national programme for monitoring long-term environmental change, the PMK programme. In all 190 species were recorded, 129 of them occurring on bark of conifers and lignum. Some species were found exclusively in forests with a long continuity. By using ordination and hierarchical classifications further species with similar habitat requirements were identified. An Indicator Species Index of Forest Continuity (ISIFC) was designed. Only two of the twenty index species occur on deciduous trees. The ISIFC was highly correlated with forest continuity and also with occurrence of species listed as threatened. Correlations with macroclimatic variables are considered sampling artifacts, and microclimatic factors are suggested to be of primary importance for species occurring in forests with a long continuity.

We have recently shown in a rut model that the acute decrease in glomerular filtration rate caused by intravenous Sandimmun® can be avoided if Cyclosporine A (CyA) is given in a fat emulsion carrier instead. The present study was undertaken to determine the immunosuppressive effect in vitro of this new formulation. The inhibitory effect on the lymphocyte responsiveness of CyA in fat emulsion carrier was compared with that of CyA dissolved in alcohol, using mitogens as well as alloantigens as stimuli. In the mixed lymphocyte culture and cell-mediated lympholysis tests and in the interleukin-2 assay, both formulations seemed equally effective. CyA in fat emulsion was somewhat less effective than CyA in alcohol in the mitogen tests. In clinical practice the fat emulsion would be rapidly metabolized, and to further evaluate our new formulation, studies in experimental Organ transplantation are needed.

Previous investigations in our laboratory have demonstrated that both acute host starvation and polyamine depletion by means of the irreversible ODC-inhibitor (ODC = ornithine-decarboxylase) fluoro-methylornithine (DFMO) lead to pronounced growth retardation of rapidly proliferating tumors. The aim of this investigation was to elucidate how these different interventions affect cell kinetics and cell cycle phases in vivo. Adult nongrowing mice (C57Bl/J) bearing a poorly differentiated rapidly growing methylcholanthrene induced sarcoma were used. Combined measurements of bromodeoxyuridine incorporation into DNA and flow cytometric techniques were used. Starvation and DFMO treatment resulted in a prolonged cell cycle transit compared to freely fed animals. Tumor cells from DFMO-treated mice demonstrated an increased time for DNA synthesis and a relatively larger accumulation of cells in the G2M phase, whereas tumor cells from starved animals were accumulated in the G0G1 phase. The fractional cell loss of tumor cell during proliferation was calculated to be around 18% higher in DFMO-treated animals compared to starved and freely fed tumor-bearing mice. This study demonstrates that different mechanisms are involved in tumor growth suppression from substrate deficiency (starvation) and from inhibition of polyamine synthesis.

Anamorphs of Mycocalicium albonigrum and M. subtile have been obtained in culture from ascospores, conidia collected in the field, and conidia produced in culture. The ontogenies of the conidiomata and conidia are described. Differences between the species with respect to cultural characteristics, septation of ascospores during germination, occurrence of chlamydospores and pyriform cells as well as ultrastructural details of conidiogenous cells and conidia were studied. Conidia are suggested to possibly be important in the dispersal of the species.