Intracellular and extracellular alkaloids of Penicillium roqueforti

The alkaloid composition of mycelium and culture liquid filtrate of the fungus Penicillium roqueforti IBPM-F-141 was studied. The new metabolite--3,12-dihydroroquefortine, a derivative of roquefortine, the main component of the alkaloid fraction of this culture, has been isolated for the first time. The structure of 3,12-dihydroroquefortine was determined by chemical and physico-chemical methods. In addition to roquefortine and 3,12-dihydroroquefortine, representatives of a new alkaloid group, the clavine alkaloids, e. g. isofumigaclavine A, isofumigaclavine B and festuclavine, were also isolated and identified. The data on the content of these compounds in mycelium and culture medium are presented.     

Histochemistry of mucosubstances in Brunner's-gland cells and duodenal goblet cells of two New World monkey species (Saimiri sciureus and Saguinus fuscicollis)

Duodenal goblet cells and Brunner's-gland cells obtained from two species of New World monkeys (Saimiri sciureus and Saguinus fuscicollis) were studied using conventional histochemical methods and by applying a panel of 17 labelled lectins. The secretions of both goblet and Brunner's-gland cells were found to contain neutral mucosubstances, while those of goblet cells also exhibit acid and sulphated carbohydrate components. Lectin binding studies allowed a more detailed analysis of the mucus glycoproteins. Marked differences between the two examined species were not detected. N-Acetyl-galactosamine, galactose, fucose and N-Acetyl-glucosamine were found to be the predominant sugar residues in Brunner's-glands glycoproteins, with mannose and glucose being only minor components.     

Evolutionary relationships among hares from North Africa (Lepus sp. or Lepus spp.), cape hares (L. capensis) from South Africa, and brown hares (L. europaeus), as inferred from mtDNA PCR-RFLP and allozyme data

Systematics and taxonomy of hares of the genus Lepus (Lagomorpha) are under contentious debate, and phylogenetic relationships among many taxa are not well understood. Here we study genetic differentiation and evolutionary relationships among North African hares, currently considered subspecies of Lepus capensis , cape hares ( L. capensis ) from the Cape province in South Africa, and brown hares ( L. europeaus ) from Europe and Anatolia, using maternally (mtDNA) and biparentally (allozymes) inherited markers. A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of a c. 1.8 kb long segment of the mitochondrial control region using eight hexanucleotide-recognizing restriction endonucleases yielded 28 haplotypes, and horizontal starch gel electrophoresis of proteins encoded by 25 structural gene loci revealed 52 alleles at 18 polymorphic loci. Diverse phylogenetic analyses (neighbor joining dendrogram, median joining network, multidimensional scaling of pairwise distances, AMOVA, F -statistics, hierarchical F -statistics) of genetic variants revealed marked substructuring of mtDNA into three phylogeographic groups, namely an African, a central European, and an Anatolian, but a somewhat less pronounced overall differentiation of the nuclear genome, despite a relatively high number of population-specific (private) alleles. However, all our results are not incongruent with Petter's (1959: Mammalia 23 , 41; 1961: Z. f. Säugetierkunde 26 , 30; 1972 : Société Des Sciences Naturelles et Physiques du Maroc 52 , 122) hypothesis that North African hares generally belong to L. capensis and that brown hares should be included in this species as well.     

Memory and Violence in the Middle East and North Africa

Memory and Violence in the Middle East and North Africa . Ussama Makdisi and Paul A. Silverstein, eds. Bloomington: Indiana University Press, 2006. 256 pp.     

Phase memory relaxation times of spin labels in human carbonic anhydrase II: pulsed EPR to determine spin label location.

Phase memory relaxation times (T(M) or T(2)) of spin labels in human carbonic anhydrase II (HCA II) are reported. Spin labels (N-(1-oxyl-2,2,5,5-tetramethyl-3-pyrrolidinyl)iodoacetamide, IPSL) were introduced at cysteines, by site-directed mutagenesis at seven different positions in the protein. By two pulse electron paramagnetic resonance (EPR), electron spin echo decays at 45 K are measured and fitted by stretched exponentials, resulting in relaxation parameters T(M) and x. T(M) values of seven positions are between 1.6 micros for the most buried residue (L79C) and 4.7 micros for a residue at the protein surface (W245C). In deuteriated buffer, longer T(M) are found for all but the most buried residues (L79C and W97C), and electron spin echo envelop modulation (ESEEM) of deuterium nuclei is observed. Different deuterium ESEEM patterns for W95C and W16C (surface residue) indicate differences in the local water concentration, or accessibility, of the spin label by deuterium. We propose T(M) as a parameter to determine the spin label location in proteins. Furthermore, these systems are interesting for studying the pertaining relaxation mechanism.     

Variability in response to UV-B among species and strains of Metarhizium isolated from sites at latitudes from 61 degrees N to 54 degrees S.

The effects of irradiances of 920 and 1200 mW m(-2) (biologically effective weighted irradiance) were examined in 2 Metarhizium album strains, 26 M. anisopliae strains, 1 M. flavoviride strain, and 1 M. taii strain isolated from sites located at latitudes from 61 degrees N to 54 degrees S. Conidia were exposed to UV-B from 1 to 6 h and subsequently examined for relative percentage culturability. Total dosage received at the end of the exposure periods ranged from 3.3 to 19.9 kJ m(-2) for the lower irradiance and from 4.3 to 25.9 kJ m(-2) for the higher irradiance. Both the irradiance values and the doses are environmentally realistic and can be observed even in temperate regions. The relationships between latitude of origin and UV-B tolerance were compared for the two levels of irradiance for the data from 1 and 2 h exposure. Exposure to both irradiances drastically reduced the relative percentage culturability of all strains. Tolerance to UV-B varied widely among strains and high variation was observed for both irradiances after all periods of exposure. After 1 h of exposure, a difference between the two irradiance levels was detectable, and this difference was magnified at longer irradiations. A significant quadratic relationship of decreasing UV-B tolerance with increasing latitude was observed after exposure of 1 and 2 h. The shape of the relationship did not differ for the two levels of irradiance. Also, we studied the effect of 1200 mW m(-2) irradiance on conidial germination time in 1 M. album strain, 7 M. anisopliae strains, and 1 M. taii strain. Exposure to UV-B delayed the germination of surviving conidia of all strains. In general, the delay in germination was directly proportional to the dose.     

Analysis of the harmonic content of the tidal flow waveforms in infants.

The aim of this study was to examine whether the spectral characteristics of tidal flow waveform reflect the interaction between the control of breathing and lung mechanics in 10 healthy infants (H), 10 infants with a history of wheezing disorders (W), and 10 infants with chronic lung disease (CLD). From the flow waveform, we calculated a shape index, the harmonic distortion (k(d)), which quantifies the extent to which a periodic signal deviates from a sine wave. The k(d) of the entire tidal flow waveform did not significantly discriminate between diagnostic groups. However, k(d) was sensitive to maturation: it increased from 0.26 at 1 mo to 0.37 at 6 mo of age (P < 0.002). Furthermore, the frequency (f) spectra of the flow (V) amplitudes between 0.13 and 10 Hz followed a power law: V(f) approximately f(-s), where s (slope) is the exponent in the power law. The exponent of the healthy infants s(H) was 4.24 [95% confidence interval (CI) = 0.2] at 1 mo, 4.39 (CI = 0.16) at 6 mo, and 4.35 (CI = 0.19) at 12 mo and not significantly changing with age. The mean value of s(W) was marginally lower (4.09 +/- 0.28; P < 0.05) than that of s(H). The mean s(CLD) was significantly lower (3.04 +/- 0.31; P < 0.001). Lower values of s and higher values of k(d) indicate an increased complexity of the feedback mechanisms determining tidal flow waveform and may be associated with disease.