Fibrinolytic activity associated with cultured human neoplastic and normal cells

Summary Fibrinolytic activity was studied in a number of different established as well as secondary human cell cultures derived from both malignant and normal tissues. The ability to degrade [¹²⁵I]-labeled fibrin was found to be characteristic of some malignant cultures as well as some normal cultures, and to be dependent upon the presence of serum. For the most part, this activity was detected in cultures with a relatively shortin vitro passage history (<30 passages). Low passaged colon and rectal carcinoma cells, HCT-8 and HRT-18, as well as normal rectal, colon and foreskin fibroblasts were positive for fibrinolytic activity, while long established (>100 passages) cultures of malignant cells (colon carcinoma, HeLa, Hep-2, KB) as well as normal cells (HEI, AV₃) were negative. It is proposed that although some normal cells synthesize plasminogen activators, the fibrinolytic capability of both malignant and normal cells may be lost on prolongedin vitro cultivation.     

Acclimatization trials of someSolanum species from Amazonas Venezuela at the botanical garden of Padova

Acclimatization trials of the two tropical speciesSolanum sessiliflorum (cocona) andSolanum stramonifolium (coconilla) from Amazonas Venezuela, were carried out at the Botanical Garden of Padua.S. sessiliflorum exhibited a greater difference between the Botanical Garden and the native environment. Plant growth was reduced and pollination was difficult; despite numerous blooms few fruits were produced. Moreover, some fruit abscised early and the persistent ones were still unripe at the end of the season. On the contrary,S. stramonifolium showed good adaptation to the new environmental conditions. The plants grew well and produced a lot of ripe berries. Self-pollination as well as cross-pollination by bumblebees (Bombus terrestris) and other insects present in the open air succeeded. Thus, this latter species could be regarded as potentially exploitable in temperate climates as well as in Venezuela.     

Does lignin modification affect feeding preference or growth performance of insect herbivores in transgenic silver birch (<Emphasis Type="Italic">Betula pendula</Emphasis> Roth)?

Transgenic silver birch (Betula pendula Roth) lines were produced in order to modify lignin biosynthesis. These lines carry COMT (caffeate/5-hydroxyferulate O-methyltransferase) gene from Populus tremuloides driven by constitutive promoter 35S CaMV (cauliflower mosaic virus) or UbB1 (ubiquitin promoter from sunflower). The decreased syringyl/guaiacyl (S/G) ratio was found in stem and leaf lignin of 35S CaMV-PtCOMT transgenic silver birch lines when compared to non-transformed control or UbB1–PtCOMT lines. In controlled feeding experiments the leaves of transgenic birch lines as well as controls were fed to insect herbivores common in boreal environment, i.e., larvae of Aethalura punctulata, Cleora cinctaria and Trichopteryx carpinata (Lepidoptera: Geometridae) as well as the adults of birch leaf-feeding beetles Agelastica alni (Coleoptera: Chrysomelidae) and Phyllobius spp. (Coleoptera: Curculionidae). The feeding preferences of these herbivores differed in some cases among the tested birch lines, but these differences could not be directly associated to lignin modification. They could as well be explained by other characteristics of leaves, either natural or caused by transgene site effects. Growth performance of lepidopteran larvae fed on transgenic or control leaves did not differ significantly.     

Field evaluation of doubled haploid plants in the Apiaceae: dill (Anethum graveolens L.), caraway (Carum carvi L.), and fennel (Foeniculum vulgare Mill.)

The Apiaceae family includes vegetables, as well as herb and spice crops. Compared to major crops, there have been few breeding or genetic improvement programs for any of the Apiaceae, especially the herb and spice species. Haploidy technology can be used to develop uniform, true-breeding lines, as well as to accelerate breeding programs. Field trials of dill (Anethum graveolens L.), caraway (Carum carvi L.), and fennel (Foeniculum vulgare Mill.) doubled haploid (DH) lines were conducted over 2–5 cropping seasons. Several of the DH dill lines had desirable agronomic characteristics such as short uniform stature along with early maturity that would be useful for crop improvement. Seed yields and the essential oil content of the seed harvested from the best performing DH dill lines were either equal to or higher than the parental line. A DH annual caraway line was identified that produced higher seed yields than the industry standard. The main constituents of the essential oil for the DH lines of both dill and caraway were similar to the parental lines. Fennel DH lines exhibited differences in height but were too late in maturity for seed production under prairie conditions. The results indicate that not only were we able to generate DH lines that could be used in a crop improvement program, but we developed DH lines that could be used directly as cultivars as these lines performed better than the industry standard (parental line).     

Analysis of different banding patterns and late replicating regions in chromosomes of Allium cepa,A. sativum and A. nigrum

Different banding procedures and preferential Giemsa staining of late replicating DNA-rich regions were carried out in metaphase chromosomes of three species belonging to different sections of the genus Allium (A. cepa, A. sativum and A. nigrum). The banding, as well as the late replicating patterns were species-specific. The late replicating pattern proved to be, in all cases, the more detailed, and represented the highest percentage of the karyotype differentially stained. Lower percents of the karyotype positively stained were accounted for by C-banding, by modified C-banding and by N-banding. In A. cepa interphase nuclei the pattern of constitutive heterochromatin fitted well with that of late replicating DNA-rich regions, but the coincidence with that revealed by C-banding was only partial. This supports the suggestion that late replicating regions may be considered to be a special category of heterochromatin. On the other hand, it seems that not all C-banded material replicates at the end of the S phase. By the modified C-banding, stained centromere dots or small bands, as well as bands at the NORs are observed.     

Molecular characterization of repetitive DNA sequences from a B chromosome

In the parasitic waspNasonia vitripennis, certain males carry a B chromosome, called PSR (paternal sex ratio), which causes the compaction and subsequent loss of the paternal chromosomes in fertilized eggs. BecauseNasonia are haplo-diploid, this leads to the production of all-male broods. Three families (PSR2, PSR18, PSR22) of related, tandemly repetitive DNAs were shown to be present solely on the PSR chromosome. These three families shared two conserved, palindromic ANA sequences, which may play a role in either PSR function or amplification of the tandem arrays. The tandem repeat family NV79 was determined to be present on the PSR chromosome as well as on at least one of the A chromosomes. This shared repeat as well as two repeat families (NV85, NV126) that were localized on the A chromosomes were detected in two sibling species ofN. vitripennis. NV79 and NV126 were also found in the more distantly related species,Trichomalopsis dubius.by H.F. Willard     

Isolation of Five Sterols from the Liverwort,Scapania parvitexta Steph.

Castasterone (1), teasterone (2), and 6-deoxocastasterone (3), as well as monoolein, monolinolein, and monopalmitin, have been identified in immature seeds of rice (Oryza sativa) as active principles in the rice lamina inclination bioassay. Castasterone, as well as monoolein and monopalmitin, were likewise identified in immature seeds of Perilla frutescens, while monopalmitin was identified as a major active principle in cultured cells of Nicotiana tabacum. It seems that the occurrence of monoglycerides in higher plants as biologically active principles might be a general feature.     

Enzymatic Formation of Hexadecenoic Acid from Palmitic Acid

Desaturation of palmitic acid was investigated in an enzyme system prepared from rat liver. 2-trans-Hexadecenoic acid as well as 9-cis-hexadecenoic acid (palmitoleic acid) were found to be formed as monoenoic acid in this system.     

Genetic Divergence and Phylogenetic Relationships in Grey Mullets (Teleostei: Mugilidae) Using Allozyme Data

Genetic divergence and phylogenetic relationships among five species of the Mugilidae family (Liza saliens, Liza aurata, Liza ramada, Chelon labrosus, and Mugil cephalus) were investigated, in the present study, on samples taken from Messolongi lagoon in Greece, using allozyme electrophoresis. Ten enzymic systems corresponding to 22 genetic loci were assayed, among which, four were found to be polymorphic in Liza saliens, Liza aurata, and Chelon labrosus, seven in Liza ramada, while only two were polymorphic in Mugil cephalus. Several loci showed different electrophoretic patterns among the species and thus, they can be useful in species taxonomy as diagnostic markers, as well as for further evolutionary studies. It must be underlined that among them the aGPD-2* locus proved to be species-specific, while the other ones can be also used in various combinations for the same purpose. The observed heterozygosity was found to range from 0.020 to 0.051. Allele frequencies of all loci were used to estimate Nei's (1972) genetic distance, which was found to range between 0.249 and 1.171 among the five species studied. UPGMA and NJ trees, obtained by genetic distance matrix methods, as well as, a tree based on the discrete character parsimony analysis were found to exhibit the same topology. Our result show that the three species of the genus Liza are clustered together, Chelon labrosus being closer to the previous clade, while Mugil cephalus being more distinct.     

Stable isotope variation of a highly heterogeneous shallow freshwater system

Food web structure is well known to vary widely among ecosystems. Recent research indicates that there can be a high degree of spatial heterogeneity within ecosystems as well. Xochimilco is a small heterogeneous freshwater system that has been transformed into a network of canals, small lakes, and wetlands. Located within Mexico City, this ecosystem has been intensively managed and highly impacted for more than 50 years. This system receives urban and agricultural runoff, with resulting impacts on water quality. The aquatic community is dominated by exotics such as carp (Cyprinus carpio) and tilapia (Oreocrhomis niloticus), though the system still supports endemic species such as the aquatic salamander, axolotl (Ambystoma mexicanum), and crayfish (Cambarellus montezumae), which are both endangered. In this study, we used carbon and nitrogen stable isotopes for the whole food web and gut content analysis from the exotic fishes to describe food web structure in different canals within Xochimilco. There were significant isotopic differences among canals. These differences may result from isotopic baseline differences as well as differences in actual food web structure: both are related to local spatial variation in water quality driven by nutrient inputs and exotic fishes. Within-ecosystem variability is likely to be seen in other perturbed shallow systems as well, and should be explicitly considered in future food web studies.     

Diversity and Abundance of Ammonia-Oxidizing Archaea and Bacteria in Diverse Chinese Paddy Soils

Ammonia-oxidizing archaea (AOA) and bacteria (AOB) in three types of paddy soils of China before and after rice plantation were investigated by using an integrated approach including geochemistry, 454 pyrosequencing, and quantitative polymerase chain reaction (PCR). The abundances of AOA amoA gene were 1～2 orders of magnitude higher than AOB amoA gene. The types of paddy soils had important impacts on the diversities of both AOA and AOB via clay mineralogy (smectite or illite-rich) and bioavailability of ammonium. The Nitrososphaera subcluster 5 and Nitrosopumilis cluster of AOA, and Nitrosomonas subcluster 5 and Nitrosospira subcluster 3 of AOB were well adapted to soils with high ammonium concentrations. AOA and AOB community structures were different before and after rice plantation, likely due to changes of pH and ammonium fertilization. The Nitrosospira subclusters 2 and 9 were well adapted to acidic paddy soils. However, the sensitivity of AOA and AOB community structures to these factors may be complicated by other geochemical conditions. The results of this study collectively demonstrated that multiple environmental factors, such as clay mineralogy, ammonium content and total organic carbon as well as soil pH, shaped AOA and AOB community structure and abundance.     

An optimized microsatellite marker set for detection of Metarhizium anisopliae genotype diversity on field and regional scales

Thirty-three Metarhizium anisopliae isolates sampled across Switzerland as well as 35 and 36 M. anisopliae isolates sampled from two field sites were assembled in three isolate collections. All isolates were analyzed using 27 newly developed and 14 previously published microsatellite markers. The 41 markers allowed for detection of 25 genotypes in the Swiss collection while 30 and 11 genotypes were detected in the two field collections. This indicated high genetic diversity on a regional as well as on a field scale. In order to improve genotyping efficiency, an optimized marker set, which allows discrimination of a large number of genotypes with as few markers as possible was developed. The optimized marker set consisted of 16 common markers, which provided resolution close to maximal resolution in all three collections (91–93 %). The results demonstrated that optimized marker sets have to be validated before large scale application to previously unassessed collections in order to avoid suboptimal resolution. This genetic tool will be valuable for analyses of genetic population structure of M. anisopliae in different habitats on a regional as well as on a field scale.     

MLO-Associated Decline of Alnus glutinosa, Populus tremula and Crataegus monogyna

In the Heidelberg area of southwestern Germany declining trees of Alnus glutinosa (L.) Gaertn. and Populus tremula L. as well as stunting shrubs of Crataegus monogyna Jacq. were observed. In all 3 species mycoplasmalike organisms, which appear to be the causal agents of the disorders, were detected by fluorescence and electron microscopy. The diseases of alder and aspen seem to be lethal while the hawthorn apparently is less affected.     

Morphology of Nyctotheroides hubeiensis Li et al. 1998 from Frog Hosts with Molecular Phylogenetic Study of Clevelandellid Ciliates (Armophorea,Clevelandellida)

The morphology of Nyctotheroides hubeiensis (Acta Hydrobiol. Sin. 1998, 22(suppl.):187), collected from the rectum of Phelophylax nigromaculatus, is presented in this paper based on detailed morphological information and molecular data. Our phylogenetic analysis showed that N. hubeiensis fell into the Nyctotheroides clade, which was strongly supported as monophyletic and clustered as basal to the genera Nyctotherus and Clevelandella. Also, the monophyly of the Order Clevelandellida and the affinity of parasitic nyctotherids and free‐living metopids were indicated in our work. The origin of clevelandellid ciliates as well as their possible evolutionary history was also discussed here; however, the analysis of more species from other vertebrate hosts (fish, reptiles) should be made before a well‐supported conclusion can be drawn.     

Cell Surface Properties of Pseudomonas syringae pv. phaseolicola Wild-type and hrp Mutants

The cell surface hydrophobicity and charge as well as surface polysaccharides of eight independent prototrophic hrp::-Tn5 mutants (Lindgren et al., J. Bacteriol. 168 , 512–522, 1986) were compared to the wild-type parent strain NPS3121 of Pseudomonas syringae pv. phaseolicola. No significant differences were found in cell surface charge, but mutant strain NPS4005 exhibited significantly lower cell surface hydrophobicity than the wild-type and the other mutant strains. The mutant strains all retained the ability to produce the exopolysaccharides (EPS) levan, a neutral fructan, and alginate, an acidic polymer. Relative amounts of EPS produced in vitro was dependent on culture conditions. Lipopolysaccharide (LPS) chemotypes were similar for all nine strains. Chemical as well as ¹³C-NMR analyses of the O-antigens from four wild-type strains of P. s. pv. phaseolicola representing two physiological races as well as the O-antigens of two strains of P. s. pv. syringae which belong to the same serogroup as P. s. pv. phaseolicola indicated that all of the O-antigens were very similar if not identical. LPS of three strains of P. s. pv. phaseolicola produced in vitro or in planta were also compared and no significant differences were detected. The altered phenotype of the Tn5 mutants of P. s. pv. phaseolicola does not appear to be due to changes in the ability to produce exopolysaccharides or to an altered composition of cell surface polysaccharides (LPS and EPS). However, a change in an unidentified cell surface component(s) leading to lowered cell surface hydrophobicity of mutant strain NPS4005 may be important.     

Arbuscular mycorrhizal fungi may serve as another nutrient strategy for some hemiparasitic species of <Emphasis Type="Italic">Pedicularis</Emphasis> (Orobanchaceae)

As an important component of plant kingdom, parasitic plants have intrigued many scientists with their heterotrophic strategy. Numerous investigations have been carried out for a better understanding of interactions between parasitic plants and their hosts. Nevertheless, studies on parasitic plants from a mycorrhizal perspective are lacking, largely because of the notion that parasitic plants do not form mycorrhizal associations. Although long being regarded as nonmycorrhizal, some Pedicularis species are recently found to be heavily colonized by mycorrhizal fungi. Because the precise information about parasitism of Chinese Pedicularis has been lacking, we surveyed both the mycorrhizal status and parasitism of 29 Pedicularis species from the northwest of Yunnan Province, China, to test the hypothesis that some Pedicularis may be mycorrhizal and parasitic simultaneously. The majority of studied species were found to be parasitic as well as mycorrhizal. In some cases, parasitic organs and arbuscular mycorrhizal fungi (AMF) were detected in the same rootlets. The results suggest that some Pedicularis species may have another nutrient strategy (e.g., mycotrophy) besides being parasitic. Also, the findings indicate that host plants as well as AMF should be taken into account in cultivation of Pedicularis species.     

Molecular detection of ochratoxin A producers: an updated review

Ochratoxin A (OTA) can be detected worldwide from various food and feed sources. It is produced byPenicillium nordicum andP. verrucosum as well as by variousAspergillus species, withA. ochraceus andA. carbonarius as the predominant producers. Various pairs of PCR primers based on AFLP, RAPD as well as primers specific to ribosomal RNA and genes coding for calmodulin and OTA biosynthetic pathway components were recently developed to detect and identify OTA producers in conventional and real-time PCR assays. Application of such assays in contaminated samples was demonstrated only in few cases. The current review gives an updated overview over the methods at hand.     

Influence of cytoskeleton organization on recombinant protein expression by CHO cells

In this study, we assessed the importance of cytoskeleton organization in the mammalian cells used to produce therapeutic proteins. Two cytoskeletal genes, Actin alpha cardiac muscle 1 (ACTC1) and a guanosine triphosphate GTPase-activating protein (TAGAP), were found to be upregulated in highly productive therapeutic protein-expressing Chinese hamster ovary (CHO) cells selected by the deprivation of vitamin B5. We report here that the overexpression of the ACTC1 protein was able to improve significantly recombinant therapeutic production, as well as to decrease the levels of toxic lactate metabolic by-products. ACTC1 overexpression was accompanied by altered as well as decreased polymerized actin, which was associated with high protein production by CHO cell cultured in suspension. We suggest that the depolymerization of actin and the possible modulation of integrin signaling, as well as changes in basal metabolism, may be driving the increase of protein secretion by CHO cells.     

Detection and differentiation of microbial siderophores by isoelectric focusing and chrome azurol S overlay

Siderophores are microbial, low molecular weight iron-chelating compounds. Fluorescent Pseudomonads produce different, strain-specific fluorescent siderophores (pyoverdines) as well as non-fluorescent siderophores in response to low iron conditions. We present an isoelectric focusing method applicable to unpurified as well as to purified pyoverdine samples where the fluorescent siderophores are visualized under UV illumination. Siderophores from different Pseudomonas sp., amongst which are P. aeruginosa, P. fluorescens and P. putida, including egg yolk, rhizospheric and clinical isolates as well as some derived Tn5 mutants were separated by this technique. Different patterns could be observed for strains known to produce different siderophores. The application of the chrome azurol S assay as a gel overlay further allows immediate detection of non-fluorescent siderophores or possibly degradation products with residual siderophore activity. The method was also applied to other microbial siderophores such as deferrioxamine B.     

Major plants foraged by bees for honey production in Ghana: mapping of bee floral sources for the development of the apicultural industry

Abstract

Honey is increasingly being used as a food supplement and to treat various diseases and disorders in Ghana. Information on floral nectar preferences of foraging honeybees is, therefore, imperative to increase production to keep pace with demand. However, in Ghana, these floral nectar preferences are yet to be investigated and identified. This study was conducted to determine bee forage sources in the three main agro-ecological honey-producing zones of Ghana. Forty-eight unblended honey samples sourced from beekeepers were analysed. Pollen spectra of the honey samples revealed 27 different pollen types of which eight were identified to family level, while 15 and four were at the level of genus and species, respectively. The results also showed that, in general, 48% of the analysed samples were unifloral honeys with the most important pollen types coming from Sapotaceae/Meliaceae, Anacardiaceae and Burkea africana. Combretaceae, Sapotaceae/Meliaceae and Anacardiaceae, as well as Lannea-type and Burkea africana were found to be the most frequent (with occurrence greater than 50%) sources of nectar utilised by bees to produce honey. The predominant pollen sources of the honeys in the three main apicultural zones of the country were Sapotaceae/Meliaceae and Anacardiaceae (Forest zone), Sapotaceae/Meliaceae and Lannea-type (Savannah–Forest transition zone) and Sapotaceae/Meliaceae, Anacardiaceae and Gynandropsis gynandra (Savannah zones). Identification of the major bee floral sources can be used as a guide by beekeepers in the location of their apiaries as well as reforesting disturbed sites with these plants to act as sources of bee forage.