Multivariate morphometric study of theCardamine pratensis group (Cruciferae) in the Carpathian and Pannonian area

A multivariate morphometric study of theCardamine pratensis group is presented, based on 84 population samples collected from the Carpathian and Pannonian area in the Czech Republic, Slovakia, Poland, Ukraine, Hungary, and Romania. Among the multivariate methods, principal component analysis, cluster analysis, and classificatory and canonical discriminant analysis were used. The analysis of chromosome numbers from all populations studied showed wide variation. The morphometric study showed that not all groups of populations characterised by their chromosome numbers and geographical criteria are morphologically, and thus taxonomically, distinguishable. Besides the morphologically well characterised speciesCardamine dentata andC. rivularis, the following species were recognised in the area studied:C. matthioli, C. majovskii andC. pratensis. Within the last species, besides the typical populations, two diploid types are provisionally recognised: type ucranica and type rivularis auct..     

Variant forms ofα-2-l-fucosyltransferase in human submaxillary glands from blood group ABH “secretor” and “non-secretor” individuals

The properties of the -2-l-fucosyltransferases in submaxillary gland preparations from blood group ABH secrefors and non-secretors were compared. The level of activity in the non-secretor gland homogenates amounted to about 5% only of that found in the secretor gland preparations. The enzymes from the two sources differed in solubility properties, charge and affinities for donor and acceptor substrates. The enzyme from secretor glands showed a preference for acceptors with Type 1 [d-galactosyl(1–3)-N-acetyl-d-glucosamine] structures whereas the enzyme from non-secretor glands had a preference for Type 2 [d-galactosyl(1–4)-N-acetyl-d-glucosamine] structures.These results demonstrate that expression of the secretor gene (Se) is associated with a molecular form of the -2-l-fucosyltransferase that is different from the species present in the same tissue when theSe gene is not expressed.     

Comparative Analysis of the Mechanisms Underlying Nifedipine-Induced Blockade of Three Subtypes of T-Type Ca2+ Channels

We analyzed the effects of nifedipine on a family of recombinant low-threshold Ca²⁺ channels functionally expressed in Xenopus oocytes and formed by three different subunits (1G, 1H, and 1I). The 1G and 1I channels demonstrated a low sensitivity to nifedipine even in high concentrations (IC₅₀ = 98 and 243 M, maximum blocking intensity A_max = 25 and 47%, respectively). At the same time, the above agent effectively blocked channels formed by the 1H-subunit (IC₅₀ = 5 M and A_max = 41%). The nifedipine-caused effects were voltage-dependent, and their changes depended on the initial state of the channel. In the case of 1G-subunits, the blockade was determined mostly by binding of nifedipine with closed channels, whereas in the cases of 1H- and 1I-subunits this resulted from binding of nifedipine with channels in the activated and inactivated states. The obtained data allow us to obtain estimates of the pharmacological properties of the above three subtypes of recombinant channels and, in the future, to compare these characteristics with the properties of low-threshold Ca²⁺ channels in native cells.     

Pollen selection for Alternaria resistance in oilseed brassicas: responses of pollen grains and leaves to a toxin of A. brassicae

Summary The effects of destruxin B, a host-specific toxin of Alternaria brassicae that causes black spot disease in oilseed brassicas, were studied on in vitro pollen germination and pollen-tube growth of Brassica campestris var brown sarson, B. juncea, B. napus cvs Westar and Cresor, B. nigra and Sinapis alba. Pollen grains of B. nigra, B. juncea and B. campestris were the most sensitive and those of S. alba the least sensitive to the toxin. Effects of the toxin were also studied on the leaves of these species, and the degree of sensitivity of leaves of different species was comparable to that of their pollen grains. The results on the responses of pollen grains as well as leaves to the toxin are in agreement with the degree of susceptibility/resistance of these species to A. brassicae reported in the literature, indicating that the genes imparting susceptibility/restistance are expressed in the pollen, a prerequisite for pollen selection. Results are also presented which show that the toxin fed to the cut end of isolated inflorescence axis is readily taken up by the developing pollen and results in the inhibition of germination of susceptible pollen. This technique offers a simple and effective method for application of selection pressure to eliminate pollen grains susceptible to the toxin from effecting fertilization.     

Callus proliferation from the protoplasts of embryogenic cells of Quercus serrata

Embryogenic culture was induced from the immature embryos of Quercus serrata using Marashige and Skoog's medium (MS) containing 0.1 M each of 2,4-d and BAP, and subcultured for seven months before isolation of protoplasts by using 1% Cellulase RS in 0.6 M mannitol solution. Efficient colony formation was obtained when protoplasts were cultured in a liquid MS medium containing 0.6 M mannitol, 3% sucrose and combination of 0.1 M or 1 M each of 2,4-d and BAP. Excluding ammonium nitrate from the MS medium resulted in the decrease of the percentage of colony formation. From colonies, both agar culture and liquid culture were sustained in the MS media without mannitol containing no plant growth regulator, or containing 0.1 M of BAP in combination with 0.1 M or 1 M of 2,4-d.Abbreviations BAP 6-benzylaminopurine - 2,4-d 2,4-dichlorophenoxyacetic acid - MS medium after Murashige & Skoog (1962).     

Tissue culture ofKarwinskia humboldtiana—a plant producing toxins with antitumoural effects

Isolated embryos ofKarwinskia humboldtiana were cultured in vitro. The growth of embryos and development to plantlets on woody plant medium supplemented with indole-3-acetic acid 6.10^-2 mol l^–1, gibberellic acid (GA₃) 3.10^-2 mol l^–1, and 6-benzylaminopurine (BA) 2 mol l^–1 was obtained. Multiplication of shoots and rooting of excised shoots has been achieved. Callus formation on modified Murashige-Skoog medium supplemented with 1-naphthaleneacetic acid 10 mol l^–1, GA₃ 14 mol l^–1, and kinetin 5 mol l^–1 on hypocotyls, or on root cultures on medium supplemented with 2.4-dichlorophenoxyacetic acid 10 mol l^–1 and BA 10 mol l^–1 was induced.Abbreviations BA 6-benzylaminopurine - 2,4-d 2,4-dichlorophenoxyacetic acid - GA₃ gibberellic acid - IAA indole-3-acetic acid - NAA 1-naphthaleneacetic acid - TEM transmission electron microscopy     

Role of mitogen-activated protein kinase pathway in reactive oxygen species-mediated endothelin-1-induced β-myosin heavy chain gene expression and cardiomyocyte hypertrophy

Endothelin-1 (ET-1) has been found to increase cardiac -myosin heavy chain (-MyHC) gene expression and induce hypertrophy in cardiomyocytes. ET-1 has been demonstrated to increase intracellular reactive oxygen species (ROS) in cardiomyocytes. The exact molecular mechanism by which ROS regulate ET-1-induced -MyHC gene expression and hypertrophy in cardiomyocytes, however, has not yet been fully described. We aim to elucidate the molecular regulatory mechanism of ROS on ET-1-induced -MyHC gene expression and hypertrophic signaling in neonatal rat cardiomyocytes. Following stimulation with ET-1, cultured neonatal rat cardiomyocytes were examined for ³H-leucine incorporation and -MyHC promoter activities. The effects of antioxidant pretreatment on ET-1-induced cardiac hypertrophy and mitogen-activated protein kinase (MAPKs) phosphorylation were studied to elucidate the redox-sensitive pathway in cardiomyocyte hypertrophy and -MyHC gene expression. ET-1 increased ³H-leucine incorporation and -MyHC promoter activities, which were blocked by the specific ET_A receptor antagonist BQ-485. Antioxidants significantly reduced ET-1-induced ³H-leucine incorporation, -MyHC gene promoter activities and MAPK (extracellular signal-regulated kinase, p38, and c-Jun NH₂ -terminal kinase) phosphorylation. Both PD98059 and SB203580 inhibited ET-1-increased ³H-leucine incorporation and -MyHC promoter activities. Co-transfection of the dominant negative mutant of Ras, Raf, and MEK1 decreased the ET-1-induced -MyHC promoter activities, suggesting that the Ras-Raf-MAPK pathway is required for ET-1 action. Truncation analysis of the -MyHC gene promoter showed that the activator protein-2 (AP-2)/specificity protein-1 (SP-1) binding site(s) were(was) important cis-element(s) in ET-1-induced -MyHC gene expression. Moreover, ET-1-induced AP-2 and SP-1 binding activities were also inhibited by antioxidant. These data demonstrate the involvement of ROS in ET-1-induced hypertrophic responses and -MyHC expression. ROS mediate ET-1-induced activation of MAPK pathways, which culminates in hypertrophic responses and -MyHC expression. Tzu-Hurng Cheng, Neng-Lang Shih: These authors have equally contributed to this work     

“Hidden” popular illnesses in primary care: Residents' recognition and clinical implications

This study documents that ethnomedical beliefs and practices play an important role in primary care in a southern community. Thirty-three of 73 patients from a rural Appalachian area coming to a university primary care internal medicine practice presented 54 ethnomedical complaints such as high blood (24.1%), Weak 'n dizzy (22.2%), nerves (16.7%), sugar (5.6%) and fallin' out (3.7%). Thirty-three patients had both biomedical and ethnomedical complaints, 40 patients had biomedical complaints without ethnomedical complaints and no patients presented with ethnomedical complaints alone. Over two-thirds of all patients consulted non-medical personnel for their complaints, mostly family and friends, and 70 percent self-treated prior to clinic consultation. Patients presenting with ethnomedical complaints when compared with those presenting with biomedical complaints sought advice of non-physicians significantly more often (p < 0.02); no statistical difference, however, was found in their self-treatment practices. Ninety-two of 130 biomedical complaints were recorded by the patient's physician but none of the 54 ethnomedical complaints were formally recorded (p < 0.001). The high incidence of ethnomedical complaints in this population and the failure of physicians to recognize these complaints demand that primary care medicine residents be taught improved history-taking skills and the essentials of ethnomedical illnesses if they are to provide culturally-sensitive patient care. [ethnomedicine; physician education; Southern black and white Appalachian folk medicine; culturally-appropriate primary care.]     

Variability and structure of natural populations of Elymus caninus (L.) L. based on morphology

Great variability involving 36 quantitative and 31 qualitative characters, as well as the habitats occupied has been shown in 18 populations of Elymus caninus from Poland, based on the detailed population and statistical analyses of morphological characters. The variability of these characters proves that the intraspecific units which have been distinguished on the basis of these characters do not have systematic significance. The two morphotypes of E. caninus (pauciflorum and caninus) described in this study will provide the basis for further genetic studies aimed at establishing their significance for considerations in the systematics of the species.It is the first paper from the series: Biodiversity of wild Triticeae (Poaceae) in Poland.     

Improvement in the quality of seed storage protein by transformation of Brassica napus with an antisense gene for cruciferin

The levels of certain essential amino acids, in particular cysteine, lysine and methionine, in the seed storage protein of a commercial spring variety of rape, Brassica napus, have been increased by the introduction of an antisense gene for cruciferin, which is the most abundant storage protein in rapeseed. The antisense construct contained part of the cruA gene in an inverted orientation, and the gene was driven by the 5 flanking region of the gene for napin such that antisense RNA was expressed in a seed-specific manner. The construct was introduced by Agrobacterium-mediated gene transfer. In self-pollinated seeds (T1 seeds) of transgenic plants there was a reduction in the levels of the 11 and 2/32/3 subunits of cruciferin, whereas the level of the 44 subunit was unchanged. The total protein and lipid contents of transgenic seeds did not differ significantly from that of normal seeds. Seeds with reduced amounts of cruciferin accumulated higher amounts of napin than non-transformed seeds, but the level of oleosin was unaffected. Amino-acid analysis of the seed storage protein revealed that T1 seeds with reduced amounts of cruciferin contained higher relative levels of three essential amino acids, namely, lysine, methionine and cysteine, with increases of 10%, 8% and 32% over the respective levels in non-transgenic seeds (B. napus cv Westar).     

Nucleotide sequence and expression of the two genes encoding D2 protein and the single gene encoding the CP43 protein of Photosystem II in the cyanobacterium synechococcus sp. PCC 7002

The unicellular photoheterotrophic cyanobacterium Synechococcus sp. PCC 7002 was shown to encode two genes for the Photosystem II reaction center core protein D2 and one gene for the reaction center chlorophyhll-binding protein CP43. These three genes were cloned and their DNA sequences determined along with their flanking DNA sequences. Northern hybridization experiments show that both genes which encode D2, psbD1 and psbD2, are expressed at roughly equivalent levels. For each of the two psbD genes, there are 18 nucleotide differences among the 1059 nucleotides which are translated. The DNA sequences surrounding the coding sequences are nearly 70% divergent. Despite the DNA sequence differences in the genes, the proteins encoded by the two genes are predicted to be identical. The proteins encoded by psbD1 and psbD2 are 92% homologous to other sequenced cyanobacterial psbD genes and 86% homologous to sequenced chloroplast-encoded psbD genes.The single gene for CP43, psbC, overlaps the 3 end of psbD1 and is co-transcribed with it. Results from previous sequencing of psbC genes encoded by chloroplasts suggest that the 5 end of the psbC gene overlaps the 3 end of the coding sequence of psbD by 50 nucleotides. In Synechococcus sp. PCC 7002, the methionine codon previously proposed to be the start codon for psbC is replaced by an ACG (threonine) codon. We propose an alternative start for the psbC gene at a GTG codon 36 nucleotides downstream from the threonine codon. This GTG codon is preceded by a consensus E. coli-like ribosome binding sequence. Both the GTG start codon and its preceding ribosome binding sequence are conserved in all psbC genes sequenced from cyanobacteria and chloroplasts. This suggests that all psbC genes start at this alternative GTG codon. Based on this alternative start codon, the gene product is 85% identical to other cyanobacterial psbC gene products and 77% identical to eucaryotic chloroplast-encoded psbC gene products.     

Cryptic growth in Klebsiella pneumoniae

Summary The ability of Klebsiella pneumoniae to grow on its own soluble lysis products is shown in a series of batch growth experiments. Maximum specific growth rate coefficients ranging from 0.69 to 1.46 h^-1 were obtained with experimental cryptic yield coefficients ranging between 0.42 to 0.52 (mg-cell-C/mg-substrate-C). These kinetic data are used to calibrate a model which demonstrates that depression of theoretical maximum yield coefficients relative to experimentally obtained values can be explained by cryptic growth phenomena without the need to resort to the use of physiologically undefined, mathematical constants. Growth of K. pneumoniae on sonicated cells derived from steady-state chemostat cultures was followed in batch culture and observed to occur with no lag phase. Batch growth curves did not indicate either diauxic or polyauxic growth, suggesting simultaneous utilization of the complex organic substrate mixture. These data suggest that cryptic growth is probably a real event occurring in growing chemostat cultures under ideal growth conditions and most probably also under starvation conditions.     

Electrogenic properties of the sodium-alanine cotransporter in pancreatic acinar cells: II. Comparison with transport models

Summary In this paper, the results of the preceding electrophysiological study of sodium-alanine cotransport in pancreatic acinar cells are compared with kinetic models. Two different types of transport mechanisms are considered. In the simultaneous mechanism the cotransporterC forms a ternary complexNCS with Na⁺ and the substrateS; coupled transport of Na⁺ andS involves a conformational transition between statesNCS andNCS with inward- and outward-facing binding sites. In the consecutive (or ping-pong) mechanism, formation of a ternary complex is not required; coupled transport occurs by an alternating sequence of association-dissociation steps and conformational transitions. It is shown that the experimentally observed alanine- and sodium-concentration dependence of transport rates is consistent with the predictions of the simultaneous model, but incompatible with the consecutive mechanism. Assuming that the association-dissociation reactions are not rate-limiting, a number of kinetic parameters of the simultaneous model can be estimated from the experimental results. The equilibrium dissociation constants of Na⁺ and alanine at the extracellular side are determined to beK _N <-64mm andK _S <-18mm. Furthermore, the ratioK _N /K _N ^S of the dissociation constants of Na⁺ from the binary (NC) and the ternary complex (NCS) at the extracellular side is estimated to be <-6. This indicates that the binding sequence of Na⁺ andS to the transporter is not ordered. The current-voltage behavior of the transporter is analyzed in terms of charge translocations associated with the single-reaction steps. The observed voltage-dependence of the half-saturation concentration of sodium is consistent with the assumption that a Na⁺ ion that migrates from the extracellular medium to the binding site has to traverse part of the transmembrane voltage.     

Erratum: Cloning and sequencing of the phycocyanin gene from Spirulina maxima and its evolutionary analysis

The genes were cloned for the two apoprotein subunits, and ,of phycocyanin from the cyanobacterium Spirulina maxima = Arthrospiramaxima) strain F3. The - and -subunit gene-coding regionscontain 489 bp and 519 bp, respectively. The -subunit gene is upstreamfrom the -subunit gene, with a 111-bp segment separating them.Similarities between the -subunits of S. maxima and nine othercyanobacteria were between 58% and 99%, as were those between the -subunits. The maximum similarity between the - and -subunits from S. maxima was 27%.     

Polymorphism of the HLA DR1 haplotype in the Israeli population investigated at the serological,cellular, and genomic levels

In the present report, we used serological, cellular, and restriction fragment length polymorphism (RFLP) to investigate the DR1 haplotype in the Israeli population. We describe an Israeli homozygous typing cell (HTC), HLA-DwLVA, which defines a new lymphocyte-activating determinant associated with Bw65, DR1 and distinct from Dwl. The parents of this donor, non-Ashkenazi Algerian Jews, are first cousins and share HLA-Cw8, Bw65, BfS, DR1, DQw1, DPw4. No specificity could be assigned to HLA-DwLVA using the 91 Ninth Workshop HTCs. Two families and forty unrelated DR1 individuals were studied with DwLVA and a panel of DR1/Dw1 HTCs. HLA-DwLVA showed segregation as a single determinant within families. This new specificity was present in 24 out of 40 (60%) unrelated DR1 individuals, indicating that in the Israeli population DwLVA is the main lymphocyte-defined determinant associated with the serologically defined DRI specificity, in contrast to non-Jewish Caucasoids where DR1 is significantly associated with Dw1. The vast majority of DwLVA-positive carriers were also Bw65 carriers, indicating that Bw65, DR1, DwLVA may represent a typical allele combination in the Israeli population. The RFLP analysis established the correlation of certain RFLPs with Dw1 and DwLVA. In addition, we describe a cluster of RFLPs that may correspond to a new Dw subtype associated with DR1, for which no serological and cellular reagents have been described so far.     

Endo-β-mannanase,the leguminous aleurone layer and the storage galactomannan in germinating seeds ofTrigonella foenum-graecum L.

The activity ofendo--mannanase in the endosperm of fenugreek seeds at different stages of germination varies pari passu with storage galactomannan breakdown.Endo--mannanase is similarly associated with the galactomannan breakdown which occurs when isolated fenugreek half-endosperms are incubated under germination conditions. Metabolic inhibitors,acting on the aleurone layer reduceendo--mannanase production in the half-endosperms in proportion to their inhibition of galactomannan breakdown.It is concluded (a) thatendo--mannanase activity, like galactomannan breakdown, is regulated by the fenugreek aleurone layer and (b) that theendo--mannanase is almost certainly instrumental in bringing about galactomannanan hydrolysis in vivo.This is part five in a series of papers dealing with galactomannan metabolism. Part four: Planta (Berl.)112, 301–308 (1973)     

Production of a novel syrup containing neofructo-oligosaccharides by the cells of Penicillium citrinum

A novel syrup containing neofructo-oligosaccharides was produced from sucrose (Brix 70) by whole cells of Penicillium citrinum. The efficiency of fructo-oligosaccharides production was more than 55% and those of the main carbohydrate components, 1-kestose (Fruf 21Fruf 21 Glc), nystose (Fruf 21Fruf 21 Fruf 21 Glc) and neokestose (Fruf 26 Glc12 Fruf), were 22, 14 and 11%, respectively.     

Ultrastructural analysis ofSpinacia oleracea sperm cells isolated from mature pollen grains

Summary In isolated condition, the sperm cells ofSpinacia oleracea are no longer arranged in pairs as in the pollen grain. The vegetative membrane, which surrounds a sperm cell pair in a mature pollen grain, is lost during the isolation procedure. The sperm cells become spherical in shape.The isolated sperm cell is surrounded by an intact plasma membrane. The heterochromatic or euchromatic sperm cell nucleus is located in the cell center. Mitochondria are round to oval and have distinct cristae. Often they are clustered in groups of 5 to 10 mitochondria. Dictyosomes are present in the cytoplasm and consist of 4 to 5 cisterns. Endoplasmatic reticulum is mostly situated at the sperm cell periphery, as single cisterns very near the plasma membrane.From diameters of sectioned sperm cells in electron micrographs, it is possible to calculate the average diameter of the whole sperm cell. This average diameter is 3.66 m with a variation of 3.0 m to 4.2 m, resulting in an average volume of 25.6 m³. The nuclear volume is 12.8 m³ (50.0% of the whole cell) and the mitochondrial volume is 0.7 m³ (2.5% of the whole cell). The frequency distribution of the isolated sperm cells diameters shows only one peak with a normal distribution, indicating that there is no dimorphism in volume.     

Asymmetric synthesis ofα-substitutedβ-amino acids using aβ-alanine derivative with two chiral handles

Summary Enantiomerically pure-substituted-amino acids have been synthesized, the key step being the diastereoselective alkylation of a-alanine derivative with two chiral handles (1S,2R,5S)-menthyl N-[(1S,2S,5S)-2-hydroxypinan-3-ylidene]-alaninate.     

Uptake of sewage derived nitrogen by<Emphasis Type="Italic"> Ulva rigida</Emphasis> (Chlorophyceae) in Bahía Nueva (Golfo Nuevo,Patagonia, Argentine)

Uptake kinetics of nitrogen derived from sewage–seawater mixtures (2.5–20% v/v effluent) were determined in the laboratory for Ulva rigida (Chlorophyceae) native from Bahía Nueva (Golfo Nuevo, Patagonia, Argentine). In terms of nitrogen concentration, experimental enrichment levels varied between 53.7 and 362.3M of ammonium and between 0.77 and 6.21M of nitrate+nitrite. Uptake rates were fitted to the Michaelis–Menten equation, with the following kinetic parameters: ammonium: V_max = 591.2molg^–1h^–1, K _s=262.3M, nitrate+nitrite: V _max=12.9molg^–1h^–1, K _s=3.5M). Both nutrients were taken up simultaneously, but ammonium incorporation was faster in all cases. The results show a high capability of Ulva rigida to remove sewage-derived nitrogen from culture media. In the field, most of the nitrogen provided by the effluent would be tied up in algal biomass, supporting low nitrogen levels found at a short distance away from the source.